Report to the Congress on

NETTING OF INTEREST ON

TAX OVERPAYMENTS AND UNDERPAYMENTS

Department of the Treasury

Office of Tax Policy

April 1997
APR 18, 1997

The Honorable Bill Archer

Chairman

Committee on Ways and Means

United States House of Representatives

Washington, D.C. 20515

Dear Mr. Chairman:

Section 1208 of Public Law 104-168, the Taxpayer Bill of Rights 2, provides that the

Secretary of the Treasury shall submit a report to the Committee on Ways and Means of the

House of Representatives and the Committee on Finance of the Senate, a study of: (1) the legal

and policy issues related to the netting of interest on federal tax overpayments and

underpayments; and (2) the Internal Revenue Service’s administrative practices in that regard. 

Pursuant to that section, I hereby submit "Netting of Interest on Tax Overpayments and

Underpayments." 

Our study concludes that while “global” interest netting would be consistent with the

intent expressed by Congress in the past, additional legislation would be necessary to achieve this

policy goal. The Administration has proposed, as part of its recently-released simplification

package, to allow "global" interest netting for income taxes with respect to tax periods not barred

by the statute of limitations. The Treasury Department’s Office of Tax Policy looks forward to

working with your Committee and your staff in developing such legislation. 

I am sending a similar letter to Representative Rangel. 

Sincerely,

/signed/

Donald C. Lubick

 Acting Assistant Secretary

 (Tax Policy)

Enclosure
APR 18, 1997

The Honorable William V. Roth, Jr.

Chairman

Committee on Finance

United States Senate

Washington, D.C. 20510

Dear Mr. Chairman:

Section 1208 of Public Law 104-168, the Taxpayer Bill of Rights 2, provides that the

Secretary of the Treasury shall submit a report to the Committee on Ways and Means of the

House of Representatives and the Committee on Finance of the Senate, a study of: (1) the legal

and policy issues related to the netting of interest on federal tax overpayments and

underpayments; and (2) the Internal Revenue Service’s administrative practices in that regard. 

Pursuant to that section, I hereby submit "Netting of Interest on Tax Overpayments and

Underpayments." 

Our study concludes that while “global” interest netting would be consistent with the

intent expressed by Congress in the past, additional legislation would be necessary to achieve this

policy goal. The Administration has proposed, as part of its recently-released simplification

package, to allow "global" interest netting for income taxes with respect to tax periods not barred

by the statute of limitations. The Treasury Department’s Office of Tax Policy looks forward to

working with your Committee and your staff in developing such legislation. 

I am sending a similar letter to Senator Moynihan. 

Sincerely,

/signed/

Donald C. Lubick

 Acting Assistant Secretary

 (Tax Policy)

Enclosure
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TABLE OF CONTENTS

EXECUTIVE SUMMARY .................................................... 1

INTRODUCTION .......................................................... 3

BACKGROUND ............................................................ 5

Basic concepts ........................................................ 5

Pre-1986 interest rules .................................................. 7

IRS administration of these rules before 1986 ................................. 8

1986 and subsequent changes in interest rules ............................... 11

Changes in the IRS administration of interest ................................ 12

Other developments ................................................... 14

TAX POLICY ISSUES INVOLVED IN INTEREST NETTING ...................... 16

Policies underlying interest on taxes ...................................... 16

Policies underlying differential interest rates ................................. 18

Policies underlying interest netting ........................................ 20

LEGAL ISSUES INVOLVED IN INTEREST NETTING ........................... 25

Congressional guidelines ............................................... 25

Approaches to global netting ............................................ 28

A. Credit/offset approach ........................................... 28

B. Interest equalization approach ..................................... 31

Limitations period considerations ......................................... 33
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ADMINISTRATIVE ISSUES INVOLVED IN INTEREST NETTING ................. 36

Annual netting ....................................................... 36

Offsetting ........................................................... 37

Global netting ....................................................... 39

Making global netting feasible ........................................... 40

CONCLUSION AND RECOMMENDATIONS ................................... 44

APPENDICES ............................................... Following page 44

APPENDIX ONE -- Notice 96-18, 1996-14 I.R.B. 27 (April 1, 1996).

APPENDIX TWO -- Persons submitting comments in response to Notice 96-18. 

APPENDIX THREE -- Witnesses at hearing September 4, 1996.

APPENDIX FOUR -- Excerpt from IRM 31(59)(31).
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EXECUTIVE SUMMARY

Since 1986, the Internal Revenue Code has required taxpayers to pay a higher rate of interest

on tax underpayments (deficiencies) than the Treasury pays on tax overpayments (credits or refunds).

The difference between the two rates (the interest rate differential) ranges from one percent to as

much as 41⁄2 percent for large corporate taxpayers.

Taxpayers can be in both an underpayment and an overpayment situation simultaneously with

respect to their federal tax liabilities, for instance if a taxpayer both owes tax for one year and is owed

a refund for another year. In various statutory provisions, and in the legislative history of the interest

rate differential provisions enacted since 1986, Congress has urged the Internal Revenue Service

(“IRS”) to “net” a taxpayer’s underpayments and overpayments so that the interest rate differential

is not charged in these situations of mutual indebtedness.

Since 1986, the IRS has followed Congress’s instructions to implement the most

comprehensive interest netting procedures that are consistent with sound administrative practice.

First, the IRS has implemented netting in cases where taxpayers temporarily have underpayments and

overpayments with respect to a single tax year -- a procedure referred to for purposes of this study

as “annual” netting. See Rev. Proc. 94-60, 1994-2 C.B. 774. The IRS also nets in all cases where

taxpayers simultaneously have outstanding tax overpayments and underpayments for different years --

a procedure referred to as “offsetting.” However, the IRS does not net interest if an overpayment

or underpayment was previously in existence but has been satisfied as of the time the netting

computation is performed (i.e., the deficiency has already been fully paid by the taxpayer and/or the

overpayment has already been fully refunded by the Government, so that one of the taxpayer’s tax

accounts has a balance of zero). This third, broader form of netting is referred to as “global” netting.

This report discusses the tax policy, legal, and administrative issues that are involved in

interest netting practices, and in particular global netting. It concludes that, in both mandating an

interest rate differential and requiring comprehensive netting to the extent feasible, Congress has

expressed inconsistent policy preferences with respect to issues such as the time value of money,

incentives for promptly settling tax accounts, and the annual accounting concept. The statutory

scheme that Congress has provided reflects to some extent this policy uncertainty, because it permits

netting in some situations but not others. In particular, while statutory authority for offsetting is set

forth in the Internal Revenue Code, see §§ 6402(a) and 6601(f), annual netting is possible based only

on a broad administrative interpretation of existing provisions (particularly § 6621), and global netting

is probably not authorized at all under current law. 

Administratively, interest computations are often extremely difficult and complex to perform

even in the comparatively straightforward annual netting and offsetting situations. Collecting and

inputting data can be very time-consuming and costly, and taxpayers and the IRS often disagree over

the appropriate analysis indicated by the data. This report describes some of the complexities of

netting computations, and it discusses the additional legal and administrative difficulties that global

interest netting could be expected to introduce if implemented.
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To date, the IRS has not implemented global netting, due primarily to uncertainty about its

authority to do so, but also because of the administrative difficulties of the necessary procedures.

Treasury and the IRS have concluded, based on this study, that the IRS cannot implement global

netting until Congress provides clear statutory authority for it. In so doing, Congress should also

clarify its preferences between the competing policy concerns that are involved. Congress has

previously concluded that comprehensive interest netting is desirable to the maximum extent feasible.

Assuming that Congress continues in this policy preference, it makes little sense for interest netting

to be available in some cases (like the annual netting or offsetting situations) but not in the global

netting situation. Accordingly, legislation authorizing global netting would be appropriate.

As for the administrative difficulties, implementing global netting may have a significant

adverse effect on IRS resources. Providing some limitations on the scope and extent of global netting

may minimize this adverse effect and make it possible for the IRS to accomplish global netting at little

additional cost. 

Treasury and the IRS therefore recommend a statutory change that will achieve the broadest

global netting that is consistent with sound administration. In particular, we recommend legislation

providing for interest equalization when taxpayers and the IRS have overlapping periods and amounts

of mutual indebtedness (taxes and refunds due). Such legislation should also authorize Treasury to

promulgate regulations incorporating our suggested limitations on this procedure. We look forward

to working with the tax-writing committees to implement these recommendations as promptly as

possible. 
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INTRODUCTION

Section 1208 of the Taxpayer Bill of Rights 2, Pub. L. No. 104-168, 110 Stat. 1453, 1473

(July 30, 1996) (TBOR 2), requires the Secretary of the Treasury to perform a study of the netting

of interest on federal tax overpayments and underpayments. Specifically, it provides as follows:

SEC. 1208. STUDY OF NETTING OF INTEREST ON OVERPAYMENTS AND

LIABILITIES.

(a) IN GENERAL. -- The Secretary of the Treasury or his delegate shall --

(1) conduct a study of the manner in which the Internal Revenue

Service has implemented the netting of interest on overpayments and

underpayments and of the policy and administrative implications of global

netting, and 

(2) before submitting the report of such study, hold a public

hearing to receive comments on the matters included in such study.

(b) REPORT. -- The report of such study shall be submitted not later than

6 months after the date of the enactment of this Act to the Committee on Ways and

Means of the House of Representatives and the Committee on Finance of the Senate.

The House Committee on Ways and Means Report sets forth the following reasons why this study

was requested:

The Committee believes that it is important for the Committee to understand

in detail how the IRS has implemented netting procedures to date. Congress has

never adopted differential interest rates, or increased the amount of such differential,

without at the same time also encouraging the IRS to implement comprehensive

interest netting procedures. The Committee is concerned that the IRS has failed to

implement comprehensive interest netting procedures and is interested in learning

whether the delay stems from technical difficulties or substantive questions about the

scope of such interest netting procedures. 

H.R. Rep. No. 506, 103d Cong., 2d Sess. 50 (1996).

The Department of the Treasury initiated this study of interest netting before TBOR 2 was

finally enacted. In Announcement 96-5, 1996-4 I.R.B. 99 (Jan. 22, 1996), Treasury and the IRS

stated:

Treasury and the IRS are beginning a formal study of issues relating to the

IRS’s current and future interest netting procedures. Treasury and the IRS will soon

issue a Notice that will ask for public comment on specific legal and administrative

issues.

1996-4 I.R.B. at 101. 
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The particular issues on which Treasury and the IRS requested public comments in connection

with this study were identified in Notice 96-18, 1996-14 I.R.B. 27 (April 1, 1996), a copy of which

is included as Appendix One to this report. The IRS received twelve written comments from

interested parties in response to Notice 96-18. A list of the persons who provided comments is set

forth in Appendix Two to this report, and the comments they submitted are available for public

inspection at the IRS in Washington, D.C. Further, in accordance with the statutory requirements

of TBOR 2, a public hearing was announced on August 19, 1996, see Announcement 96-75, 1996-34

I.R.B. 29, and was held on September 4, 1996, in Washington D.C. A list of the five persons who

testified at that hearing is set forth in Appendix Three.

The study of these issues was performed primarily by the Department of the Treasury’s Office

of Tax Policy and the IRS. The comments and testimony of the interested parties noted above have

been carefully taken into account in this study and in the preparation of this report. Treasury and the

IRS wish to thank all those who submitted comments or testified in connection with this study. We

appreciate the public’s willingness to assist us in examining the policy, legal, and administrative issues

related to the IRS’s interest netting practices. 
 Except where otherwise noted, all references to the “Code” or “IRC” are to the Internal 1/

Revenue Code of 1986.

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BACKGROUND

Determining the amount of interest owed to or by taxpayers in connection with their federal

tax liabilities may involve relatively complicated and time-consuming computations for both taxpayers

and the IRS. The complexity of such calculations is primarily due to the interaction of the Internal

Revenue Code provisions governing interest on tax liabilities with other, more general, procedural 1/

provisions of the Code. Accordingly, any study of current interest netting procedures must

commence with a review of these basic concepts and Code provisions. 

This section first examines the authorities in the Internal Revenue Code that govern the

manner in which the IRS handles each taxpayer’s account. These provisions reflect an historical

concept that each kind of tax due, for each period, from each taxpayer is a separate and distinct

liability. 

This section then reviews the relevant statutory rules governing the calculation of interest with

respect to federal tax liabilities. These rules are found in sections 6601 and 6611 of the Internal

Revenue Code. It then focuses on section 6621 and the changes that have been made to that

provision since 1986. The “interest netting issue” can be traced largely to the interest rates set by this

provision. Specifically, the interest netting issue derives from the fact that taxpayers are both charged

interest on their unpaid tax liabilities and paid interest on their overpayments of taxes. If the interest

rates on underpayments and overpayments are the same, then the net interest due or payable will be

zero whenever underpayments and overpayments overlap in time and dollar amounts. If the

underpayment and overpayment interest rates are not equal, however, then the method by which

imbalances are applied against each other can be critical in determining whether there is any net

interest due or payable.

This report focuses on federal income taxes. The same concepts and statutory provisions

generally apply, however, to federal employment, excise, gift, and estate taxes, although those taxes

may be subject to different technical rules. 

Basic concepts

One of the most fundamental principles of federal income taxation, which Congress and the

courts have repeatedly endorsed, is that each taxpayer’s income tax liability for a single tax year is

a separate and distinct liability. Although this is not a necessary feature of an income tax -- some tax

theorists have argued that the most appropriate tax base may be income over the course of the

taxpayer’s lifetime rather than just in a single year -- it is a basic convenience that makes our current

system manageable. The Code is structured to reflect this central concept, and a substantial amount

of federal tax practice and procedure turns on it.
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For instance, the Code generally requires that taxable income of every taxpayer must be

computed on the basis of that taxpayer’s taxable year, see IRC § 441(a), and that each taxpayer must

prepare and file returns on an annual basis, see IRC §§ 6012, 6072. Courts have also routinely held

that the liability for each year’s tax from each taxpayer constitutes a separate cause of action or claim

for relief. Commissioner v. Sunnen, 333 U.S. 591 (1948). This rule prevents taxpayers from

litigating a single year’s tax in multiple court proceedings (i.e., “splitting” a cause of action), and it

has significant consequences for res judicata and collateral estoppel purposes.

In implementing its responsibility to assess and collect all federal income taxes, see generally

IRC §§ 6201, 6301, the IRS has generally adhered to the concept that every tax liability for a single

tax year is separate and distinct. For example, the IRS’s main computer system for tracking taxpayer

accounts (the “Master File”) is organized by “modules,” each of which represents a taxpayer’s liability

for a specific kind of tax (e.g., income or employment taxes) for a single tax period (tax year or

quarter). Income tax examinations are typically devoted to a selected cycle of years (modules) for

the taxpayer under examination.

While the Code and the Treasury Regulations contain literally hundreds of provisions that

implement the fundamental legal and accounting concept that each liability is separate and distinct,

they also provide a number of exceptions to this general principle. For example, the installment sale

provisions, see IRC § 453 et seq., the inventory accounting rules, see IRC § 471 et seq., the original

issue discount provisions, see IRC § 1271 et seq., and even the elementary distinction between

expenditures that must be capitalized and those that can be deducted as “ordinary and necessary”

business expenses are all intended to reflect economic reality better than the annual income

accounting concept would otherwise permit. Similarly, the rules permitting carryovers and

carrybacks of net operating loss deductions or certain credits between tax years, see IRC §§ 172, 39,

illustrate Congress’s recognition that, without some provision for relief, the annual income tax

concept could potentially lead to arbitrary or distorted results. See, e.g., Libson Shops, Inc. v.

Koehler, 353 U.S. 382, 386 (1957) (carrybacks “ameliorate the unduly drastic consequences of taxing

income strictly on an annual basis”). 

The Code also grants the IRS some discretion concerning how to apply overpayments made

by a taxpayer to the taxpayer’s outstanding liabilities for different periods. Section 6402(a)

authorizes the Secretary to credit or refund certain overpayments by taxpayers:

In the case of any overpayment, the Secretary, within the applicable period of

limitations, may credit the amount of such overpayment, including any interest

allowed thereon, against any liability in respect of an internal revenue tax on the part

of the person who made the overpayment and shall, subject to subsections (c) and (d),

refund any balance to such person.

IRC § 6402(a). This provision uses the permissive term “may” when referring to the Secretary’s

offset authority; by contrast, refund of overpayments is made mandatory by use of the term “shall.”

Similarly, 
- 7 -

In the case of a tax payable in installments, if the taxpayer has paid as an installment

of the tax more than the amount determined to be the correct amount of such

installment, the overpayment shall be credited against the unpaid installments, if any.

IRC § 6403.

As further evidence that each tax liability is considered separate and distinct, the Code

provides for the payment of interest on every tax liability -- interest to the taxpayer in the case of an

overpayment of tax and interest to the Government in the case of an underpayment of tax. See

generally IRC §§ 6601, 6611. 

Pre-1986 interest rules

While interest has been charged on underpayments of federal taxes since shortly after the Civil

War, it was not until 1921 that interest was provided for overpayments of federal taxes. In 1921,

Congress set the rate for overpayment interest at one-half of one percent per month (6% per annum),

the same as the existing underpayment interest rate. Internal Revenue Act of 1921, Pub. L. No. 67-

98, § 1324, 42 Stat. 227, 316. At times between 1921 and 1935, the underpayment interest rates for

estate taxes and excise taxes were raised to encourage taxpayers to pay those taxes promptly. E.g.,

Internal Revenue Act of 1924, Pub. L. No. 68-176, § 274(f), 43 Stat. 253, 297; H.R. Rep. No. 179,

68th Cong., 1st Sess. 30 (1924). Conversely, on at least one occasion, Congress eliminated interest

on overpayments of excise taxes “to discourage delay in claiming credit or refund and to discourage

litigation.” H.R. Rep. No. 708, 72d Cong., 1st Sess. 39 (1932); Revenue Bill of 1932, Pub. L. No.

72-154, § 621(c), 47 Stat. 169, 268. Generally, however, from 1939 until 1986 the overpayment and

underpayment rates were the same for all taxes. Special treatment -- and special interest rates -- have

persisted for certain taxes; for instance, a special 4% rate still applies to certain estate taxes for which

the payment date is extended. See IRC §§ 6601(j), 6166.

Since 1954, the Code has provided that taxpayers who underpay their taxes generally must

pay interest to the Government on the amount of the underpayment for the period running from the

date payment was due until the date payment is made. Section 6601(a) of the Code provides:

GENERAL RULE.--If any amount of tax imposed by this title (whether

required to be shown on a return, or to be paid by stamp or by some other method)

is not paid on or before the last date prescribed for payment, interest on such amount

at the underpayment rate established under section 6621 shall be paid for the period

from such last date to the date paid. 

Likewise, if a taxpayer has overpaid taxes, the Code provides that the Government shall pay interest

on the overpaid amount for the period beginning with the date of the overpayment and ending when

the overpayment is credited or refunded to the taxpayer. Section 6611(a) provides that “[i]nterest

shall be allowed and paid upon any overpayment in respect of any internal revenue tax at the

overpayment rate established under section 6621.” Section 6611(b) states that:
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PERIOD.--Such interest shall be allowed and paid as follows:

(1) CREDITS.--In the case of a credit, from the date of the

overpayment to the due date of the amount against which the credit is taken.

(2) REFUNDS.--In the case of a refund, from the date of the

overpayment to a date (to be determined by the Secretary) preceding the date

of the refund check by not more than 30 days.

Interest running in either direction has, since 1982, been compounded daily. IRC § 6622(a).

The running of interest in either direction can be suspended for various reasons. For example,

if the Commissioner makes notice and demand for the payment of taxes, and the tax is paid within

21 calendar days after the date of the notice and demand (10 business days if the amount due exceeds

$100,000), then interest is not imposed for the period after the date of the notice and demand. IRC

§ 6601(e)(3) (as amended by TBOR 2). Similarly, the Government is not liable to the taxpayer for

interest on an overpayment if the overpayment is refunded or credited within 45 days after the due

date for filing the return of such tax, or if the Government otherwise pays a taxpayer’s claim for

refund within 45 days after it is filed. IRC §§ 6611(e)(1), (e)(2). 

Interest computations can be substantially complicated by the presence of carryover tax

attributes from another tax year. For example, if a net operating loss deduction is carried back to a

tax year pursuant to section 172, or a credit is carried back pursuant to section 39, interest on a

resulting overpayment in the carryback year will generally not begin to run until the due date of the

return for the credit or loss year. IRC § 6611(f). Likewise, if an underpayment for one tax year is

reduced due to such a carryback from another year, interest is still due on the full underpayment

amount up through the due date of the return for the credit or loss year and on the reduced

underpayment amount only after that date. IRC § 6601(d).

Certain interest is statutorily prohibited or is limited to specific time periods as a matter of

law. These “restricted interest” computations can be particularly complex for large corporate

taxpayers, which commonly have multiple carrybacks and carryovers of different credits and

deductions over any given period of years and are subject to multi-year audits. As will be discussed

in more detail below, the IRS does not have the capability to perform all restricted interest

computations automatically on its Master File system. Instead, many of these complex calculations

must be performed manually (i.e., using stand-alone computer or calculator systems with data

manually inputted).

IRS administration of these rules before 1986

As noted above, section 6402(a) of the Code permits the IRS to credit a taxpayer’s

overpayment of one tax liability against a liability for another tax. The Treasury Regulations have

long provided for the crediting of overpayments against underpayments in accordance with this

provision. The pertinent regulation, Treas. Reg. § 301.6402-1, provides:
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The Commissioner, within the applicable period of limitations, may credit any

overpayment of tax, including interest thereon, against any outstanding liability for

any tax (or for any interest, additional amount, addition to the tax, or assessable

penalty) owed by the person making the overpayment and the balance, if any, shall be

refunded, subject to subsection 6402(c) and (d) and the regulations thereunder, to that

person by the Commissioner.

In accordance with the regulation, the IRS has generally implemented section 6402(a) by

applying overpayments only against a taxpayer’s other outstanding (unpaid) liabilities. See generally

IRM (22)000. If an outstanding underpayment for one kind of tax or tax period exists at the same

time that the taxpayer has an overpayment for a different tax or period, the IRS will usually apply the

balance of the overpayment against the underpayment before refunding any amount to the taxpayer.

If more than one such underpayment exists, the overpayment will generally be applied to the “oldest”

underpayment (the one that arose earliest in time) in order to reduce the accrual of further

underpayment interest due from the taxpayer. If there are no currently outstanding liabilities at the

time the overpayment arises, the IRS will refund the overpayment to the taxpayer. The IRS refers

to the procedure described in this paragraph as “offsetting,” and henceforth in this study that term

will be reserved for this practice. 

Offsetting -- crediting an overpayment against an outstanding liability pursuant to section

6402(a) -- has been performed by the IRS for many years. Indeed, offsetting is performed

automatically at the Master File when an overpayment and an outstanding underpayment register on

the system simultaneously. Courts have confirmed, however, that offsetting under section 6402(a)

is discretionary; the IRS is permitted to offset overpayments against deficiencies but is not required

to do so. Northern States Power v. United States, 73 F.3d 764 (8th Cir.), cert. denied, 117 S.Ct. 168

(1996); Kalb v. United States, 505 F.2d 506, 509 (2d Cir. 1974), cert. denied, 421 U.S. 979 (1975);

Acker v. United States, 519 F.Supp. 178, 182 (N.D. Ohio 1981); Mounts v. United States, 95-2

U.S.T.C. (CCH) ¶ 50,399 (S.D.W.Va. 1995).

A special interest rule applies in the offsetting situation. Section 6601(f) provides:

If any portion of a tax is satisfied by credit of an overpayment, then no interest

shall be imposed under this section on the portion of the tax so satisfied for any period

during which, if the credit had not been made, interest would have been allowable

with respect to such overpayment. 

Ordinarily, interest on an underpayment would be charged to a taxpayer under section 6601

irrespective of the existence of other overpayments by the same taxpayer; likewise, interest on an

overpayment would ordinarily accrue to the benefit of the taxpayer pursuant to section 6611

regardless of the existence of the taxpayer’s other underpayments. If the underpayment interest rate

and the overpayment interest rate are equal, then, to the extent that the underpayment and the

overpayment overlap temporally (i.e., exist at the same time) and in amount, the interest calculations

are duplicative. When an underpayment is satisfied by the application of an overpayment by the same
 This example makes certain simplifying assumptions. For instance, in the example interest 2/

is compounded only on an annual basis, whereas the Code requires that it be compounded daily,

see IRC § 6622(a). Likewise, interest rates may actually vary on a quarterly basis as the Federal

short-term rate fluctuates, see IRC § 6621(b), although this rule did not apply to the years in the

example. A constant 6% rate is used here simply for hypothetical purposes.

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taxpayer, pursuant to section 6402(a), then section 6601(f) permits the IRS to avoid computing

interest on the underpayment for the amount and period of mutual indebtedness. 

An example is perhaps the best way to illustrate the interaction of the interest rules with

sections 6402(a) and 6601(f). Assume that a taxpayer had an underpayment (i.e., owed tax) in the

amount of $1,000 for tax year 1983, starting with the return filing date of April 15, 1984. Assume

further that the taxpayer had an overpayment (i.e., was entitled to a refund) of $600 for 1984, starting

with the return filing date of April 15, 1985. Finally, assume that the computations are being made

as of April 15, 1986, and that the interest rate for both overpayment and underpayment interest is

6%.2/

Ordinarily, the taxpayer would owe underpayment interest on the 1983 deficiency of $1,000

for the two-year period from April 15, 1984 through April 15, 1986, computed as follows:

Tax due 4/15/84 = $1,000.00

Interest 4/15/84 - 4/15/85: $1,000 x 6% = $60.00

Interest 4/15/85 - 4/15/86: $1,060 x 6% = $63.60

Total interest = $123.60

Total tax plus interest due as of 4/15/86 = $1,123.60

The Government would also owe the taxpayer interest on the 1984 overpayment of $600 for the oneyear period from April 15, 1985, through April 15, 1986, as follows:

Overpayment arises 4/15/85 = $600.00

Interest 4/15/85 - 4/15/86: $600 x 6% = $36.00

Total refund plus interest as of 4/15/86 = $636.00

When the amount owed by the taxpayer is netted against the money owed to the taxpayer, the net

underpayment as of April 15, 1986 equals $1,123.60 minus $636.00, or $487.60.
 Mathematically, for interest rate “Y” and tax amounts “A” and “B,” then for any period of 3/

time:

Y x (A + B) = (Y x A) + (Y x B).

This will continue to hold true if “A” is a positive value (tax owed to the Government) and “B” a

negative one (refund owed to the taxpayer), or vice versa.

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From an overall perspective, as of April 15, 1985, the taxpayer really owed the Government

only $460, consisting of $400 in tax (i.e., the $1,000 deficiency for 1983, less the $600 refund due

for 1984) plus $60 in interest (6% interest on the $1,000 deficiency for the period April 15, 1984

through April 15, 1985). While the Code treats the two tax amounts as separate, section 6402(a)

permits the IRS to offset the $600 overpayment against the $1,000 outstanding deficiency as soon

as it becomes available (i.e., on April 15, 1985). Pursuant to section 6601(f), the taxpayer is not

charged underpayment interest to the extent of the offset amount during the period of mutual

indebtedness, or between April 15, 1985 and April 15, 1986. Instead, during that period the taxpayer

owes interest only on the net balance due. Interest will accordingly be calculated as follows: 

Tax due 4/15/84 = $1,000.00

Interest 4/15/84 - 4/15/85: $1,000 x 6% = $60.00

Total tax plus interest due as of 4/15/85 = $1,060.00

Credit for overpayment as of 4/15/85 = ($600.00)

Adjusted tax plus interest due as of 4/15/85 = $460.00

Interest 4/15/85 - 4/15/86: $460 x 6% = $27.60

Net underpayment as of 4/15/86 = $487.60

As this example illustrates, both methods ultimately arrive at the same net underpayment

figure for the taxpayer. This is because calculating interest on two amounts and then netting the

results will always mathematically yield the same figure as first netting the amounts and then doing

the interest computation, assuming the rates used are the same in both instances. The calculations 3/

of interest become slightly more complex, however, and the application of netting principles becomes

more important, because of the new interest rate rules that Congress enacted in 1986 and subsequent

years. 

1986 and subsequent changes in interest rules

In 1986, Congress for the first time enacted different rates of interest for underpayments and

overpayments, providing that the interest rate on tax underpayments was to equal the Federal short-
- 12 -

term rate plus 3 percentage points, while the interest rate on tax overpayments was to equal the

Federal short-term rate plus 2 percentage points. Tax Reform Act of 1986, Pub. L. No. 99-514,

§ 1511(a), 100 Stat. 2085, 2744 (1986). The 1986 amendment to section 6621 applies for purposes

of determining interest for periods after December 31, 1986. Id., § 1511(b). This means, in effect,

that the different rates apply to the balances due and balances payable (i.e., both underpayments and

overpayments) for all pre-1986 tax years that were still outstanding as of the end of 1986, as well as

to new tax liabilities that arose after 1986.

Congress increased the section 6621 underpayment rate for large corporate underpayments

in 1990. Omnibus Budget Reconciliation Act of 1990, Pub. L. No. 101-508, § 11341(a), 104 Stat.

1388, 1388-470. Under this provision, if a C corporation has an underpayment for any tax period

that exceeds $100,000, the applicable underpayment rate of interest is the Federal short-term rate plus

5 percentage points, rather than the Federal short-term rate plus 3 points that applies to other

underpayments. IRC § 6621(c)(1), (3).

In 1994, Congress again amended the interest provisions, reducing the interest payable to

large corporate taxpayers on certain overpayments under section 6621(a) by 1.5 percentage points.

Uruguay Round Agreements Act, Pub. L. No. 103-465, §713, 108 Stat. 4809, 5001 (1994). Under

the revised provision, the interest payable on corporate overpayments of more than $10,000 is

reduced from the Federal short-term rate plus 2 percentage points to the Federal short-term rate plus

0.5 percentage points. IRC § 6621(a)(1)(last sentence). 

As a consequence of these amendments, the differential between the interest rate paid by the

Government on large corporate overpayments (under section 6621(a)) and the maximum interest rate

paid by C corporations on large corporate underpayments (under section 6621(c)) is now 4.5

percentage points.

Changes in the IRS administration of interest

The IRS has improved its administration of the new interest rate structure since 1986. First,

offsetting has become more critical since the interest rate differential of section 6621 was enacted.

To the extent an underpayment and an overpayment overlap in time and amount, section 6601(f)

operates to nullify the interest rate differential. In accordance with that provision, no interest is

imposed on the portion of an underpayment that is satisfied by the offsetting application of an

overpayment from another tax period. Likewise, no overpayment interest is paid to the taxpayer with

respect to the offset amount and period. Section 6601(f) thus has the effect of completely eliminating

the interest rate differential with respect to the amount that is offset for the period of the overlap in

time. However, the interest rate differential continues to be an issue to the extent an underpayment

is not fully satisfied by the crediting of an overpayment.

The IRS has also implemented enhanced interest netting procedures in Rev. Proc. 94-60,

1994-2 C.B. 774. Under this procedure, which is referred to as “annual” interest netting, the IRS will

consider all increases and decreases in a taxpayer’s liabilities within a single tax year before applying
 The IRS has long had procedures for applying and computing restricted interest within a 4/

single tax year. See Rev. Proc. 60-17, § 3, 1960-2 C.B. 942.

- 13 -

the statutory interest rate to the resulting net underpayment or overpayment for that year. As a

4/

consequence, the taxpayer ultimately gets charged only one interest rate, depending on the net

balance at the time of the adjustment. Support for this approach lies in the concept that a taxpayer

does not really have an “underpayment” or “overpayment” of a particular kind of tax for a given tax

period until the correct amount of tax for that period is finally determined. See generally IRC § 6211

(definition of “deficiency”). 

The IRS’s position, however, is that it still does not perform "global” interest netting. The

global netting situation is somewhat similar to the offsetting situation in theory, for it involves

utilizing (at least for interest purposes) a taxpayer’s overpayment of one tax liability to affect the

taxpayer’s underpayment of another tax liability. Unlike offsetting, however, the balance

(underpayment or overpayment) for one of the taxes that is going to be utilized in the computation

has already been paid, and there is neither any further tax or interest due from the taxpayer, nor any

tax or interest payable by the Government, with respect to that tax. In a global netting computation,

in other words, the balance in one of the tax accounts equals zero. The IRS’s position is that it will

perform offsetting only, not global netting. Overpayments will be applied against underpayments only

if the overpayment and the underpayment are both outstanding, i.e., not in a zero balance, at the time

of the computation. See Treas. Reg. § 301.6402-1. 

Several commentators have alleged that offsetting is applied inconsistently by IRS Field

Offices and Service Centers, that offsetting is sometimes used as a negotiating chip against taxpayers

in settling cases at Appeals, or that some local offices will perform global netting while others will

not. Although Treasury and the IRS National Office are aware of these complaints, we believe

offsetting is generally performed properly and are unaware of actual instances where true global

netting has been performed. It bears repeating that the Master File is programmed to perform

offsetting automatically, and we are unaware of circumstances where it has not done so. By contrast,

no Master File mechanism exists for global netting (quite apart from the uncertain legal authority or

the capability of IRS employees to perform it). It is also possible that the complaints are caused by

some confusion over terminology. Situations in which comprehensive offsetting has occurred may

have been erroneously characterized as “global” netting, leaving other taxpayers to complain that their

requests for actual global netting have been unfairly denied.

At any rate, in response to the request of many commentators, Treasury and the IRS wish to

make very clear the current IRS policy with respect to offsetting. It is the IRS’s policy to maximize

offsetting, and the resulting interest savings to taxpayers, whenever there is a true offsetting situation,

i.e., whenever overpayments and underpayments are simultaneously outstanding.

Because the IRS has already implemented interest netting in many situations in accordance

with Congress’s directions, global netting presently remains the only significant form of netting that
- 14 -

the IRS has not yet adopted. Thus, global netting, and in particular the policy, legal, and

administrative issues related to it, is the principal focus of the remainder of this report. 

Other developments

Several civil tax cases have recently considered interest netting issues, although two involved

offsetting and only one clearly addressed the global netting situation. In Pettibone Corp. v. United

States, 34 F.3d 536 (7th Cir. 1994), the IRS examined the corporate taxpayer’s income taxes for the

13-year period preceding its bankruptcy. The taxpayer and the IRS agreed to the amounts of

underpayments and overpayments for each year, many of which resulted from net operating loss

carrybacks. 34 F.3d at 539. The IRS “netted these overpayments and underpayments to establish

the total tax liability” by “following its established procedures” under section 6402(a). 34 F.3d at

538 (emphasis added). The court ultimately held that such netting did not amount to a prohibited

setoff under the Bankruptcy Code.

Focusing on the court’s shorthand summary of the Government’s argument (“the IRS argued

for continuous netting of overpayments, underpayments, and interest on the balance”), several

commentators have assumed that Pettibone involved global netting and have concluded that the IRS

does indeed perform global netting on a selective basis. A similar argument was made by the taxpayer

in Northern States Power Co. v. United States, 73 F.3d 764 (8th Cir.), cert. denied, 117 S.Ct. 168

(1996). As the court in Northern States Power realized, however, that contention is erroneous.

Close reading of the Pettibone case clearly demonstrates that offsetting, not global netting, was at

issue: the netting involved the crediting of outstanding overpayments against outstanding

underpayments pursuant to section 6402(a). As a consequence, “nothing in that decision [Pettibone]

suggests netting is required when past underpayments have already been fully paid.” 73 F.3d at 769.

Some commentators have similarly suggested that another case demonstrates that the IRS

occasionally performs global netting. See United States v. Midway Industrial Contractors, Inc. (In

re Midway Industrial Contractors, Inc.), 178 Bankr. 734 (N.D. Ill. 1995). Again, however, Midway

involved offsetting with respect to unpaid (outstanding) liabilities pursuant to sections 6402(a) and

6411(b) (relating to tentative refund adjustments). See 178 Bankr. at 735-36. Thus Midway is not

a global netting case.

The only case to have addressed true global netting is Northern States Power. In that case,

five years (1980 through 1984, inclusive) were at issue, and the taxpayer had initially overpaid for

two of them (1981 and 1982). In 1990, the IRS proposed deficiencies for four of the years (1980,

1981, 1983, and 1984), and although the taxpayer disagreed with the deficiencies, it promptly paid

them. The parties ultimately agreed that the deficiencies totaled less than the amounts paid, and they

stipulated to the amount of the overpayments for all five years. 73 F.3d at 765. Global netting was

involved because the taxpayer argued that the IRS should credit its 1981 and 1982 overpayments to

the agreed deficiencies for 1980, 1983, and 1984 as of the time those deficiencies arose (the return

due dates for the deficiency years), even though at those times the 1980, 1983 and 1984 tax years did

not have any underpayments due and bore zero balances.
- 15 -

The Government argued that overpayments can only be credited against “outstanding”

liabilities pursuant to section 6402(a) and Treas. Reg. § 301.6402-1, and moreover that such crediting

was at the IRS’s discretion. The Eighth Circuit agreed on both counts. With respect to the authority

for crediting in such situations, the Court stated:

We agree with the United States that the word “liability” in Section 6402

means “outstanding liability,” one that is unpaid when the credit is made. The

Treasury regulations support this reading, see 26 C.F.R. § 301.6402-1 (referring to

an “outstanding liability”), and we properly defer to these regulations. See Cottage

Savings Ass’n v. Commissioner, 499 U.S. 554, 560-61 (1991) (courts “must defer to

[the Commissioner’s] regulatory interpretations of the Code so long as they are

reasonable”); Miller v. United States, 65 F.3d 687, 689 (8th Cir. 1995) (same). This

is also the reading that makes the most sense, because only an outstanding liability can

be “satisfied” by a credit. See IRC § 6601(f). NSP provides no support, other than

a strained reading of miscellaneous bits of legislative history, for its assertion that

section 6402(a) is somehow “time-neutral,” that a “liability” may be one that no

longer exists, but once did. We think this argument withers before the statute’s plain

meaning. We are likewise not convinced by NSP’s attempt to read the word

“outstanding” out of the relevant Treasury regulation, 26 C.F.R. § 301.6401-2. In

our view, the regulation means what it says. 

So there must be an outstanding tax liability, against which an overpayment

may be credited, before section 6402's netting exception comes into play.

73 F.3d at 767 (emphasis in original). The court also agreed with the Government’s claim that

crediting under section 6402(a) was discretionary:

even assuming [an outstanding] liability, the IRS has discretion whether to credit an

overpayment to that liability or not. Section 6402 is clear: the IRS “may credit the amount

of such overpayment . . . against any liability.” 

Id. (emphasis in original). The court summarized its holding as follows: 

Thus, the IRS may credit an overpayment against an outstanding liability, and, if it

does, section 6601(f)’s netting provision comes into play. In this case, however, not

only has the IRS apparently chosen not to credit the overpayments, there were no

outstanding liabilities against which the overpayments might be credited. . . . Under

section 6402, then, the IRS could not credit the overpayments, and so section

6601(f)’s netting rule does not apply.

73 F.3d at 768.

The holding of Northern States Power set forth above reflects the IRS’s view of the law with

respect to global netting. This report now turns to the policy, legal, and administrative issues that

would be raised if the IRS’s interest netting practices were expanded to cover global netting. 
- 16 -

TAX POLICY ISSUES INVOLVED IN INTEREST NETTING

The practice of interest netting, and in particular global netting, involves several different, and

sometimes competing, tax policies. The basic requirement that interest be paid on imbalances in

federal tax accounts is premised on fundamental economic concepts regarding the use of money.

Related considerations underlie the post-1986 differential in the interest rates for overpayment and

underpayment interest. The use of netting to minimize that differential during periods of mutual

indebtedness invokes another set of policy concerns. At one time or another in the legislative history

of the interest rate provisions, Congress has mentioned all of these policy goals as justifications for

its actions. Some of these underlying policies are, however, at least arguably incompatible. 

This section discusses the various policy goals that are involved in the interest provisions of

the Code, the interest differential, and Congress’s countervailing desire for broader interest netting.

It concludes by suggesting possible methods to reconcile these competing goals.

Policies underlying interest on taxes

“Interest” is fundamentally a charge or compensation for the use or forbearance of another’s

money. See, e.g., Deputy v. DuPont, 308 U.S. 488, 498 (1940); Old Colony R. Co. v.

Commissioner, 284 U.S. 552, 560 (1932). Courts have similarly stated that compensation for the use

of money is the principal, or even the only, rationale for charging interest with respect to tax

deficiencies or overpayments. See Manning v. Seeley Tube & Box Co., 338 U.S. 561 (1950); Avon

Products, Inc. v. United States, 588 F.2d 342 (2d Cir. 1978); Alexander Proudfoot Co. v. United

States, 454 F.2d 1379, 1384 (Ct. Cl. 1972); May Department Stores Co. v. United States, 36 Fed.

Cl. 680 (1996). However, these broad statements subsume a number of related theories that

individually may justify charging interest: that interest reflects the fungibility and time value of

money; that it provides incentives for prompt satisfaction of debts; or that it is compensation for the

risk of lending money and collecting unpaid debt.

First, the fungibility and time value of money provide a basic justification for interest on tax

debts. A fundamental premise underlying financial markets is that a dollar payable in the future is

worth less than a dollar paid today. The discount may be attributable to alternative investments (e.g.,

prevailing rates of return, including interest rates) as well as inflation and the parties’ expectations

(concerning risk and the credit-worthiness of the debtor, etc.). Interest accordingly must be charged

on any debt in order to leave the creditor whole. The failure to charge interest on a tax debt

(underpayment or overpayment) for which payment is long-delayed would leave the creditor (either

the Government or the taxpayer) worse off for having the right to be paid than if that party had been

paid immediately and sought alternative investments.

Some courts have considered the time value of money, particularly the parties’ expectations

concerning inflation, to be a primary purpose of the interest rules in the Code. For example, in

Mounts v. United States, 95-2 U.S.T.C. (CCH) ¶ 50,399 (S.D.W.Va. 1995), the court, citing

Latterman v. United States, 872 F.2d 564, 467 (3d Cir. 1989), stated: 
- 17 -

the purpose of § 6601 is to allow the government to recover amounts due in ‘real’

(inflation-adjusted) dollars. . . . . When a taxpayer owes the government money and

delays payment after the date on which payment was due, the government should not

have to suffer a depletion in real dollars because of that delay and, conversely, the

taxpayer should not reap the benefit of delaying payments, thereby in effect

diminishing the amount owed.

Interest also provides some incentive for the prompt satisfaction of debts. If taxpayers were

not charged interest on their tax underpayments, they would not only lack incentives to pay their

taxes promptly, they would in fact have a positive incentive not to pay promptly. Because money is

fungible, it would be economically rational for them to use their funds for other investment purposes,

for which they presumably could obtain a competitive market rate of return, and to delay satisfaction

of their tax debts. The Government would have an incentive to do the same thing if interest were not

charged to it and payable to taxpayers on tax overpayments.

Congress has long recognized the relationship between interest rates and the promptness with

which tax debts are paid. E.g., H.R. Rep. No. 179, 68th Cong., 1st Sess. 30 (1924) (explaining that

the Internal Revenue Act of 1924 raised underpayment rates to encourage payment). More recently,

Congress implicitly recognized this when it permitted the interest rate on both underpayments and

overpayments to “float” with market rates in 1979. See Act of December 29, 1979, Pub. L. No. 96-

167, § 4(b), 93 Stat. 1275. It also expressly relied on this rationale in enacting the interest rate

differential in 1986, stating that the lack of a differential “may cause taxpayers either to delay paying

taxes as long as possible to take advantage of an excessively low rate” in comparison with the rest

of the economy “or to overpay to take advantage of an excessively high rate.” H.R. Rep. No. 426,

99th Cong., 1st Sess. 849 (1985), reprinted in 1986-3 C.B. (Vol. 2) 849; S. Rep. No. 313, 99th

Cong., 2d Sess. 184 (1986), reprinted in 1986-3 C.B. (Vol. 3) 184. Providing that a tax-related debt

in either direction bears a market-related interest charge neutralizes (or at least reduces) the

advantages that could otherwise be obtained by avoiding payment and investing elsewhere.

Consequently, interest charges in both directions are necessary to prevent giving either taxpayers or

the Government perverse incentives to fail to settle their tax accounts.

In the commercial world, interest also provides compensation for the risk of non-payment and

the costs of collection. Thus, trustworthy borrowers with established credit histories can generally

obtain loans at a lower interest rate than borrowers who may not be so reliable. Unlike interest on

commercial debts, however, tax interest is not clearly related to risk or the creditworthiness of the

“borrowing” party. This may be due in part to the fact that neither the Government nor the taxpayer

has any choice but to deal with each other. There is no competitive market for taxes or tax debts.

In particular, the Government typically has little choice whether it will “extend credit” to taxpayers

who fail or refuse to pay their taxes. It must take on as its “customer” anyone who neglects or

refuses to pay taxes in a timely fashion. Likewise, taxpayers cannot choose to pay taxes to another

agency in order to obtain a better interest rate on their temporary overpayments. Nor does the

Federal Government engage in the sale of tax debts in order to make such a market or shift the risk

of non-collection, as some localities do for property tax debts. Finally, individualized negotiations
 Post-1986 amendments to section 6621 have expanded on this basic structure, setting 5/

special rates for corporate overpayments to the extent they exceed $10,000, see IRC § 6621(a)(1)

(second sentence), and for “large corporate underpayments,” see § 6621(c). 

- 18 -

over the terms and conditions governing a tax debt, in particular the applicable interest rate, would

plunge the system into administrative chaos. Flat statutory rates are a practical convenience needed

to administer the tax system fairly.

In other ways, however, Congress has to some extent treated tax liabilities as if they were

similar to ordinary commercial debts, and the Code reflects this treatment. For instance, in 1982

Congress repealed a provision that had prevented interest from compounding, as interest ordinarily

does on commercial indebtedness, and revised the Code to provide specifically that interest must be

compounded daily. Tax Equity and Fiscal Responsibility Act of 1982, Pub. L. No. 97-248, § 344,

96 Stat. 324, 635; IRC § 6622(a). This treatment is also reflected in the requirement that interest be

charged and paid on imbalances running in both directions. See H.R. Rep. No. 426, 99th Cong., 1st

Sess. 849 (1985), reprinted in 1986-3 C.B. (Vol. 2) 849; S. Rep. No. 313, 99th Cong., 2d Sess. 184

(1986), reprinted in 1986-3 C.B. (Vol. 3) 184. If temporary imbalances in tax liabilities are treated

just like other commercial transactions in the economy between parties that are independent,

unrelated, and operating at arm’s length, then it follows that an interest charge is appropriate. The

interest requirement thus demonstrates Congress’s belief that tax debts are simply a species of “loan”

from the taxpayer to the Government (overpayments), or vice versa (underpayments).

Policies underlying differential interest rates

Section 6621 of the Code, the provision setting the interest rates, most clearly reflects

Congress’s determination to treat tax indebtedness in accordance with commercial concepts. Since

1986, section 6621(a) has set two different interest rates -- one for overpayments and another for

underpayments. Both rates are tied to the “Federal short-term rate,” a rate defined in sections

5/

6621(b) and 1274(d) that generally reflects short-term market interest rate conditions. The “basic”

overpayment and underpayment rates differ by one percent: the overpayment rate equals the Federal

short-term rate plus 2 percentage points, while the underpayment rate equals the Federal short-term

rate plus 3 percentage points.

The rationale for enacting the one percent differential was set forth, in identical language, in

the House Committee on Ways and Means report and the Senate Committee on Finance report that

accompanied the 1986 amendment to section 6621:

The committee is concerned that [the Code’s] interest provisions are not

modeled sufficiently closely on other interest rates in the economy; this may have

distortive effects. First, the committee is concerned that both the interest rate

taxpayers pay the Treasury and the rate the Treasury pays to taxpayers are the same

rate. Few financial institutions, commercial operations, or other entities borrow and

lend money at the same rate. Thus, either the rate taxpayers pay the Treasury or the
- 19 -

rate the Treasury pays taxpayers is necessarily out of line with general interest rates

in the economy. This distortion may cause taxpayers either to delay paying taxes as

long as possible to take advantage of an excessively low rate or to overpay to take

advantage of an excessively high rate. Consequently, the committee has approved a

one-percent differential between these two interest rates.

H.R. Rep. No. 426, 99th Cong., 1st Sess. 849 (1985), reprinted in 1986-3 C.B. (Vol. 2) 849; S. Rep.

No. 313, 99th Cong., 2d Sess. 184 (1986), reprinted in 1986-3 C.B. (Vol. 3) 184. 

First, the committee reports highlight Congress’s perception that a single interest rate for both

underpayments and overpayments “is necessarily out of line with general interest rates in the

economy” (emphasis added). If capital markets were perfect one might be able to borrow and lend

at the same rate, but financial institutions and other commercial operations in fact employ different

rates depending on whether they are borrowing or lending. (The differences may be due to market

imperfection and the assumption by lenders of the risk of non-payment.) Thus prevailing market rates

for borrowing and lending differ. Using a single rate for both borrowing and lending, as the United

States had been doing prior to 1986 for tax underpayments and overpayments, inevitably means that

the rate used will differ from at least one, or perhaps both, of the prevailing rates for those activities

in the rest of the economy. According to the Congressional reports, using different rates for

overpayments and underpayments is necessary to avoid, or at least reduce, the inevitable distortion

that would come from using a single rate.

Further, this discussion indicates Congress’s concern that the potential for distortion between

tax interest rates and other interest rates in the economy could lead sophisticated taxpayers to

manipulate their tax liabilities into an overpayment or underpayment posture in order to maximize the

differential with available returns in the rest of the economy. Congress thus recognized that, while

some such arbitrage opportunities were unavoidable, they should be minimized to the extent possible.

Otherwise, taxpayers might delay paying taxes, if the underpayment rate were too low relative to

prevailing rates in the economy, or overpay their taxes, if the overpayment rate were excessively high.

Imposing differential interest rates more in keeping with the prevailing economic rates reduces the

incentive to indulge in such manipulations. 

Finally, this excerpt indicates that Congress felt the IRS should act more like “financial

institutions, commercial operations, or other entities” that “borrow and lend money” at differing rates.

This reinforces the view that Congress thought of tax debts in commercial terms, treating an

underpayment as if it were a loan from the Government to the taxpayer and an overpayment as a

borrowing by the Government from the taxpayer. It follows from the analogy to financial or

commercial institutions that the Government, like any other commercial entity in the marketplace,

should charge a higher interest rate on the money it lends (underpayments) than on the money it

borrows (overpayments), which is precisely what Congress enacted.

It is interesting to note that in enacting an interest differential for tax debts Congress never

mentioned one of the principal factors that drives interest charges in the marketplace, the relative risk
- 20 -

of a loan and the creditworthiness of a potential debtor. As noted above, this is probably in part

because there is no market for taxes or individualized negotiation of tax interest rates. Further, the

underpayment and overpayment interest rates do not reflect the real risk of non-payment to either the

Government or taxpayers. For example, Congress has imposed on the United States an overpayment

interest rate that exceeds the “risk-free” rate that the Government pays when it borrows on the open

market. See IRC §§ 6621(a), 1274(d) (defining applicable Federal rates by reference to marketable

obligations of the United States, which are essentially risk-free). If risk or creditworthiness were

considered, however, the underpayment rates would vary with the borrower, as commercial loans do,

and the overpayment rate would reflect only the applicable Federal rates, since the risk of nonpayment by the Government is essentially zero. Risk and creditworthiness thus do not appear to be

reflected in the interest rates Congress has chosen with respect to tax debts.

Policies underlying interest netting

In the economy as a whole, most participants are simultaneously both borrowers and lenders

to some extent. It is commonplace for commercial entities to owe each other overlapping or

offsetting debts, particularly in longstanding or established business relationships, such as that

between a bank and its customer, a wholesaler and a retail merchant, or two firms that provide

services to each other. Most individuals likewise have some savings or investment accounts that pay

them interest at the same time they are paying interest on automobile loans or home mortgages.

It may be questioned whether the fungibility and time value of money rationales for charging

interest that are discussed above make sense when two economic entities simultaneously owe each

other offsetting liabilities. To the extent of the overlapping indebtedness, neither party really has the

use of the other’s funds, since the amounts negate each other for a period of time. Interest clearly

continues to provide some insurance against the risk of non-collection and some incentives for timely

payment (or penalties for untimely payment). But at least to the extent of the overlapping

indebtedness, these risks and incentives also offset each other. Further, the same goals can be

accomplished through self-help, i.e., non-payment or direct offset of the common amounts (although

such self-help may have collateral costs or may not be permitted by law). Thus the fungibility and

time value of money rationales for a net interest charge may not be persuasive.

In most situations in our economy, however, the fact that two parties have overlapping or

offsetting liabilities to each other does not prevent the separate accrual of interest on each debt.

Ordinarily, the two liabilities are accounted for separately; the debts are not set off against each other

before principal and interest are paid, nor typically are the interest payments themselves netted.

In part, the general failure to net offsetting liabilities is due to the wide diversity of the kinds

of accounts that parties in a complex economy may have with each other and the difficulty of relating

those accounts for bookkeeping purposes. Consider, for example, an individual investor who holds

a bond of the same major corporation from which the investor buys and finances an automobile. The

bond (which is essentially a loan from the investor to the corporation) and the automobile financing

indebtedness (a loan from the corporation to the individual) will likely have dramatically different
 These cases involved the issue whether offsetting and the resulting interest netting was 6/

required where the taxpayers had offsetting liabilities for different taxes, such as income taxes and

excess profits tax. The courts found that offsetting was not required in these situations. As

discussed below, however, the cases involved tax years prior to the inclusion of sections 6402(a)

and 6601(f) of the Code. Under current law, the separate liabilities discussed in the cases could at

the IRS’s discretion be offset against each other pursuant to those provisions.

- 21 -

terms, accruing and paying interest at different times and using different rates, amortization schedules,

methods of payment, etc. Further, the two debts may be entered with different corporate subsidiaries

and, because both obligations may be freely traded in secondary markets, their owners may change

more or less frequently. The practical difficulties of offsetting such simultaneous debts before

computing and paying a “net” principal or interest amount would in cases like this be nearly

insurmountable. Multiply this complexity millions of times throughout the economy and the general

failure to net principal or interest payments is easily understandable.

Even in an ongoing relationship between just two parties, however, netting of offsetting

liabilities is not the ordinary commercial practice. Banks or other financial institutions typically do

not net the principal amounts of deposits and loans involving the same customer before computing

the net interest due, nor do they directly net the two interest payments themselves, even though the

bookkeeping for such netting would be comparatively simple and could in many cases be performed

by a single accounting function within the bank. Indeed, netting is the exception rather than the rule,

for the most part limited to the relatively rare situations in which the parties are making a final

settlement of their debts against each other and discontinuing further business -- for example, upon

the bankruptcy or other debt restructuring of one of the parties.

The Code similarly anticipates that in general each federal tax will be treated as a separate

liability and will be accounted for separately. Courts have thus frequently held that different kinds

of taxes (such as excise, income, or employment taxes) are different liabilities that are not accounted

for together. E.g., United States v. Hecla Mining Co., 302 F.2d 204, 213 (9th Cir. 1961); Babcock

& Wilcox C. v. Pedrick, 212 F.2d 645, 649 (2d Cir. 1954); W.G. Duncan Coal Co. v. Glenn, 120

F.Supp. 948, 949-50 (D. Ky. 1952). Even in the income tax context, the Code is structured around 6/

the annual accounting concept and the notion that each tax year’s tax liability is separate. As noted

previously, there are many exceptions to this basic structure -- net operating loss and business credit

carrybacks and carryforwards, offsets under § 6402(a), etc. -- but they are the exceptions, not the

general rule.

Congress recognized that, because of the separate accounting for separate tax liabilities,

taxpayers can simultaneously be underpaid with respect to some taxes and overpaid with respect to

others. It provided early on for some degree of netting if the Government found itself in a situation

of mutual indebtedness with a taxpayer. For example, in the predecessor to section 6402(a) of the

Code, the Internal Revenue Code of 1939 provided that overpayments of income tax “shall be

credited against any income, war-profits, or excess-profits tax or installment thereof then due from

the taxpayer, and any balance shall be refunded.” Internal Revenue Code of 1939, § 322(a), 53 Stat.
- 22 -

1, 91. In 1949, Congress added a discretionary element to this crediting procedure, providing that

“the Commissioner may, in his discretion, in lieu of refunding an overpayment of tax . . . credit such

overpayment against any tax due from the taxpayer.” Act of August 27, 1949, § 9, 63 Stat. 666, 669

(adding § 3770(a)(4) to the Internal Revenue Code of 1939). These provisions were merged into

section 6402(a) of the Code in 1954, and, as discussed previously, the offsetting procedure described

by that provision has remained in place since then.

Congress likewise has recognized that such mutual liabilities were tantamount to overlapping

loans between the parties. Unlike the typical commercial situation where parties have offsetting debts

with each other, taxpayers who are both borrowers and lenders with respect to the Government --

who have both underpaid taxes and overpaid taxes -- are accorded the benefits of netting in some

situations pursuant to section 6601(f). Congress discussed this precise scenario in the legislative

history of the 1986 amendment to section 6621:

Section 6601(f) provides that, to the extent a portion of tax due is satisfied by

a credit of an overpayment, no interest is imposed on that portion of the tax.

Consequently, if an underpayment of $1,000 occurs in year 1 and an overpayment of

$1,000 occurs in year 2, no interest is imposed in year 2 because of the rule in section

6601(f). 

H.R. Conf. Rep. 841, 99th Cong., 2d Sess. II-785 (1986), reprinted in 1986-3 C.B. (Vol. 4) 785.

Further, both times Congress has revisited the interest rate provisions since 1986, it has repeated that

interest is netted in offsetting situations under sections 6402 and 6601, and it has urged the Secretary

to implement “the most comprehensive netting procedures under section 6402 that are consistent with

sound administrative practice.” See H.R. Conf. Rep. No. 964, 101st Cong., 2d Sess. 1101 (1990),

reprinted in 1991-2 C.B. 591; S. Rep. No. 412, 103d Cong., 2d Sess. 144 (1994); H.R. Rep. No.

826, Part I, 103d Cong., 2d Sess. 178 (1994), reprinted in 1995-1 C.B. 254. 

However, Congress has never articulated a clear policy reason why interest should be netted

in the offsetting situation, or for that matter in any other situation. The legislative history quoted

above -- in which Congress encourages interest netting at the same time that it is enacting significant

interest differentials between underpayments and overpayments -- instead gives contradictory policy

signals. On the one hand, three times in the last eleven years Congress has increased the differential

between interest paid on refunds and interest charged on deficiencies, in each case reiterating one or

more of the traditional rationales for interest -- time value of money, incentives for prompt payment,

running taxation more like other financial functions in the economy, etc. At the same time, however,

Congress has simultaneously urged netting to ameliorate the impact of the very interest differentials

it has repeatedly adopted.

In urging “the most comprehensive netting procedures . . . consistent with sound

administrative practice,” Congress has implicitly endorsed several long-term policy shifts without

explicitly examining the fundamental premises underlying them. For example, expanded use of

netting represents a further erosion of the concept of separate tax liabilities -- a shift that Congress
- 23 -

has undertaken elsewhere (in such provisions such as the carryback and carryforward of net operating

losses or business credits) only after serious policy consideration is given to the consequences. While

it may be intuitively appealing for taxpayers to keep a single "running balance" with the IRS and

constantly be “netting out” the interest on temporary underpayments and overpayments, the shift to

such a system should be deliberate and recognized for what it is. 

Global interest netting, which by definition takes into account tax years that have a zero

balance, also has profound implications for the concept of finality. Under the current system, statutes

of limitation generally bar the reconsideration of a taxpayer’s liability, by either the taxpayer or the

IRS, after a certain period of time has passed. See generally IRC §§ 6501, 6503, 6511. The principal

rationale for finality is that it permits “repose” to the parties; after a certain time taxpayers know that

they cannot be audited and that the amount of their tax liability is permanently fixed. Limitations

periods also prevent the litigation of stale conflicts in which evidence becomes increasingly difficult

to collect, as memories are blurred, documents discarded, etc.

Several commentators have suggested, however, that global netting should be available

whenever zero balance years overlap temporally with outstanding liabilities -- a fairly common

situation -- even if adjustments to the tax liability for the zero balance year are barred by the

applicable statute of limitations. The principal argument that has been made for extending global

netting even to statute-barred years is to analogize it to net operating loss or credit carrybacks (or,

less frequently, carryforwards) under sections 172 or 39, which can affect the tax liability in otherwise

barred years. Such carryback provisions, however, are statutory exceptions to the general model of

separate tax liabilities for separate years which have their own independent policy justifications. No

other independent policy justification is given for netting interest in statute-barred years.

Likewise, the argument that taking statute-barred years into account for global netting

purposes is somehow “fairer” than leaving such years alone also directly conflicts with the primary

policy rationale for statutes of limitations. Statutes of limitation are by definition “unfair”: they cut

off claims that might otherwise be legitimate, based upon a considered decision that other policy goals

like finality and repose outweigh the claims. Alone, therefore, an amorphous claim of “unfairness”

is not a sufficient reason for an exception to a limitations period.

Some commentators also have argued that limiting global netting to open (non-statute barred)

tax years will lead taxpayers to continue extending their statutes of limitations on zero balance tax

years in order to retain the prospect of global netting for interest computation purposes. This

argument ignores several factual realities, however. First, extensions of the limitations period expose

the taxpayer to additional examination and assessments by the IRS. Most taxpayers seek to foreclose

that possibility, and it will be the rare taxpayer for whom the prospect of global interest netting

overrides the goal of closing a taxable year. Further, extensions generally require agreement by the

IRS as well as the taxpayer, so unilateral action by a taxpayer to retain the chance of global netting

is unlikely.
- 24 -

Perhaps the most policy persuasive argument for implementing more comprehensive interest

netting is that Congress has already indicated its preference for “the most comprehensive netting

procedures . . . consistent with sound administrative practice.” As discussed below in the legal

section of this report, it is not clear that Congress ever envisioned the global netting situation, and

the statutory authority for implementing netting probably does not extend so far. Nevertheless netting

has been clearly authorized by Congress in at least some situations (the annual netting and offsetting

cases). It makes little sense from a policy standpoint to permit interest netting in some factual

circumstances but not in others, particularly when the difference between the permissible and

impermissible netting situations turns on the comparatively trivial question of whether there is a zero

balance or an outstanding balance due one way or the other.

Other factual uncertainties as to how global netting would work prevent much specificity as

to its effects on taxpayers. Some restrictions to make global netting administratively feasible are

suggested below -- such as limiting it to non-statute-barred years, requiring taxpayers to provide

necessary documentation, etc. The taxpayers who meet these conditions and thus could take

advantage of global netting are probably only larger corporate taxpayers and a few very wealthy

individuals. As a practical matter only those who have multiple-year open examinations are likely

even to consider whether the potential savings from global netting are worth the cost of compiling

the data and performing the calculations. 

A final policy consideration that must be taken into account in enacting global netting is its

potential revenue impact. Interest netting will always lose revenue in comparison to a non-netting

baseline, because it eliminates some or all of the interest rate differential in section 6621, which

always runs in the Government’s favor. Global netting simply eliminates the differential for more

years and more taxpayers than offsetting or annual netting. The ultimate revenue impact of global

netting will depend on the limitations imposed on it.
- 25 -

LEGAL ISSUES INVOLVED IN INTEREST NETTING

This portion of the report discusses the authorities for netting and in particular whether global

netting is currently permitted under the Code. The “Background” section above set forth the

provisions of current law that permit the IRS to net overpayments and underpayments of tax. This

section reviews the Congressional guidance for the interpretation of these provisions that is found in

the legislative history of the amendments to section 6621. It then provides examples of the two

general approaches to global interest netting that have been recommended by taxpayers and analyzes

whether those approaches are permitted under current law. Finally, certain period of limitations

aspects of global netting are discussed.

Congressional guidelines

As discussed above, in 1986 Congress for the first time enacted a differential between the

interest rate that taxpayers paid the Government on underpayments and the interest rate that the

Government paid taxpayers on overpayments. In enacting the interest differential, Congress

recognized that a taxpayer might have both an overpayment and an underpayment of tax outstanding

at the same time and potentially accruing interest at different rates. The Senate report states:

Taxpayers subject to differential interest rates may have an underpayment for

a type of tax in one taxable year and an overpayment for the same type of tax in

another taxable year.

S. Rep. No. 313, 99th Cong., 2d Sess. 185 (1986), reprinted in 1986-3 C.B. (Vol. 3) 185. The

Conference Report provides an example illustrating when interest netting under section 6601(f) would

be applicable:

Section 6601(f) provides that, to the extent a portion of tax due is satisfied by

a credit of an overpayment, no interest is imposed on that portion of the tax.

Consequently, if an underpayment of $1,000 occurs in year 1 and an overpayment of

$1,000 occurs in year 2, no interest is imposed in year 2 because of the rule in section

6601(f). 

H.R. Conf. Rep. 841, 99th Cong., 2d Sess. II-785 (1986), reprinted in 1986-3 C.B. (Vol. 4) 785. 

Both the Senate Report and the Conference Report then go on to discuss the potential for

administrative problems if an interest rate differential were enacted. The Senate Report states:

The IRS requires substantial lead time to develop the data processing capability to net

such underpayments and overpayments in applying differential interest rates. The bill,

therefore, provides that the Secretary of the Treasury may prescribe regulations

providing for netting of tax underpayments and overpayments through the period
- 26 -

ending three years after the date of enactment of the bill. By that date, the committee

expects that the IRS will have implemented computerized netting procedures.

S. Rep. No. 313, 99th Cong., 2d Sess. 185 (1986), reprinted in 1986-3 C.B. (Vol. 3) 185. Similarly,

the Conference Report provides:

The IRS can at present net many of these offsetting overpayments and

underpayments. Nevertheless, the IRS will require a transition period during which

to coordinate differential interest rates with the requirements of section 6601(f). The

Senate amendment, therefore, provides that the Secretary of the Treasury may

prescribe regulations providing for netting of tax underpayments and overpayments

through the period ending three years after the date of enactment of the bill. By that

date, the IRS should have implemented the most comprehensive netting procedures

that are consistent with sound administrative practice.

H.R. Conf. Rep. 841, 99th Cong., 2d Sess. II-785 (1986), reprinted in 1986-3 C.B. (Vol. 4) 785. 

In accordance with this legislative history, section 1511(b) of the Tax Reform Act of 1986

authorized regulations providing for the netting of underpayments and overpayments:

COORDINATION BY REGULATIONS.--The Secretary of the Treasury or his

delegate may issue regulations to coordinate section 6621 of the Internal Revenue

Code of 1954 (as amended by this section) with section 6601(f) of such Code. Such

regulations shall not apply to any period after the date 3 years after the date of

enactment of this Act.

Treasury and the IRS did not, however, issue any regulations pursuant to the authority

granted under this provision. As the excerpts from the legislative history illustrate, interest

computations became substantially more complex once differential interest rates were added to the

credit/offset regime of sections 6402(a) and 6601(f). But the basic principles of that regime were

unchanged by the addition of differential interest rates, and the existing regulations under those

sections already provided sufficient authority to implement “the most comprehensive netting

procedures that are consistent with sound administrative practice.” Thus no additional regulations

were necessary to implement the new interest rates.

Some commentators have argued that section 1511(b) of the 1986 Act and its accompanying

legislative history demonstrate that Congress envisioned not just offsetting but global netting when

it enacted the interest rate differential. They contend that section 1511(b) constitutes a shorthand

authorization for Treasury to implement global netting. According to these commentators, the

provision does not make sense unless Congress intended global netting to be in place at the end of

the three-year period stated in section 1511(b).
- 27 -

This argument, however, is not supported by the actual language Congress used in the reports

and authorizing provision. The reports excerpted above refer only to “offsetting,” “underpayments,”

and “overpayments;” the prospect of applying credits and liabilities against zero-balance tax years for

interest netting purposes is never mentioned. Further, in accordance with the existing credit/offsetting

scheme, Congress cited only section 6601(f) in both the reports and section 1511(b). But section

6601(f) applies only “if any portion of a tax is satisfied by credit of an overpayment,” and as the court

held in Northern States Power, citing section 6601(f), “only an outstanding liability can be ‘satisfied’

by a credit.” 73 F.3d at 767. Finally, section 1511(b) merely authorizes regulations that "coordinate"

section 6621 with section 6601(f). It does not provide any statutory basis for interest netting beyond

that which is otherwise contained in section 6601(f). Likewise, section 6621, which is limited to

imposing different rates on underpayments and overpayments, provides no basis for interest netting.

Certainly section 1511(b) is an indication of Congressional intent regarding interest netting.

Just as clearly, however, Congress only envisioned reconciling differential interest rates with the

existing credit/offset scheme, not the creation of an additional netting practice. 

This conclusion is confirmed by Congress’s subsequent deliberations. When Congress

increased the interest rate for large corporate underpayments under certain circumstances in 1990,

see Omnibus Budget Reconciliation Act of 1990, Pub. L. 101-508, § 11341(a), 104 Stat. 1388, 1388-

470, the Conference Report commented on interest netting as follows: 

Under present law, the Secretary has the authority to credit the amount of any

overpayment against any liability under the Code (sec. 6402). To the extent a portion

of tax due is satisfied by a credit of an overpayment, no interest is imposed on that

portion of the tax (sec. 6601(f)). The Secretary should implement the most

comprehensive crediting procedures under section 6402 that are consistent with sound

administrative practice.

H.R. Conf. Rep. No. 964, 101st Cong., 2d Sess. 1101 (1990), reprinted in 1991-2 C.B. 591. Here,

Congress expressly referred not only to section 6601(f) but also to the credit rules of section 6402(a)

in connection with its discussion of interest netting procedures.

Again, when Congress amended the interest provisions in 1994, see Uruguay Round

Agreements Act, Pub. L. No. 103-465, § 713, 108 Stat. 4809, 5001 (1994), the legislative history

discussed netting practices as follows:

Under present law, the Secretary of the Treasury has the authority to credit

the amount of any overpayment against any liability under the Code (section 6402).

To the extent a portion of tax due is satisfied by a credit of an overpayment, no

interest is imposed on that portion of the tax (section 6601(f)). The Secretary should

implement the most comprehensive crediting procedures under section 6402 that are

consistent with sound administrative practice, and should do so as rapidly as is

practicable.
- 28 -

S. Rep. No. 412, 103d Cong., 2d Sess. 144 (1994); see also H.R. Rep. No. 826, Part I, 103d Cong.,

2d Sess. 178 (1994), reprinted in 1995-1 C.B. 254. As in 1990, Congress referred to sections 6402

and 6601(f) as the source for the mechanical rules by which it contemplated interest netting would

be accomplished. 

Some taxpayers have argued that the 1990 and 1994 committee report language again

provides a Congressional mandate directing Treasury to implement global netting. This legislative

history does indicate that Congress was concerned about ameliorating the effect that larger interest

rate differentials would have when an underpayment is satisfied by a credit of an overpayment. But

the legislative history provides no basis for interest netting other than as authorized under existing

law. Congress instead referred repeatedly to the existing statutes that permit the IRS to net interest

under the credit/offset regime (i.e., sections 6402 and 6601(f)). Moreover, the legislative history's

consistent use of the phrase "is satisfied by a credit" supports the view (discussed in more detail

below) that interest netting can only occur if there are actual credits of overpayments against

outstanding liabilities. 

Approaches to global netting

There are generally two conceptual ways to implement global netting, which will be referred

to as the “credit/offset approach” and the “interest equalization approach.” Although some variations

may exist in specific proposals, the two approaches are generally representative of the views of

taxpayers who submitted comments in connection with this study.

The IRS already uses both the credit/offset and interest equalization models, in different

contexts. The credit/offset approach is very similar to the method for offsetting under section

6402(a). Congress has provided clear statutory authority for it (in limited situations) and, as

discussed previously, has referred to it in enacting the interest differential provisions. The

credit/offset approach does not, however, apply well in the global netting situation, particularly in

certain fact scenarios.

The interest equalization approach is the conceptual premise for annual netting, as adopted

by the IRS in Rev. Proc. 94-60, and the Commissioner’s Advisory Group advocated extending it to

global netting situations in 1993. However, interest equalization is not provided for by the Code in

any factual context that involves tax liabilities for more than one year.

A. Credit/offset approach

The "credit/offset approach" is basically an extension of the IRS’s current offsetting

methodology under section 6402(a). The principal difference is that in the global netting situation an

overpayment could be credited to an underpayment of tax irrespective of whether the overpayment

or underpayment exists as of the time of the adjustment. Under this approach, credits would be

allowed “as if” the overpayment had not previously been refunded or the underpayment had not

previously been paid.
- 29 -

Some taxpayers maintain that section 6402(a) already provides the IRS with the authority to

allow such treatment. If so, section 6601(f) would automatically allow interest netting, since that

section is a self-executing provision that effectively nets interest during periods of mutual

indebtedness, once a liability is satisfied by a credit. The credit/offset approach cannot be

implemented, however, because current law does not provide the authority to apply a previously

refunded overpayment as a credit against a deficiency, or an overpayment as a credit against a

previously paid deficiency. 

Section 6402(a) presently applies only where credit is made against “outstanding” liabilities.

The regulation under section 6402 clearly states that overpayments can be credited only against

outstanding tax liabilities:

The Commissioner, within the applicable period of limitations, may credit any

overpayment of tax, including interest thereon, against any outstanding liability for

any tax (or for any interest, additional amount, addition to the tax, or assessable

penalty) owed by the person making the overpayment and the balance, if any, shall be

refunded, subject to subsection 6402(c) and (d) and the regulations thereunder, to that

person by the Commissioner.

Treas. Reg. § 301.6402-1. Since a liability that has been paid is not “outstanding,” and since global

netting relies on crediting overpayments against previously paid liabilities for interest netting

purposes, it follows that global netting is not authorized by the regulations. The court in Northern

States Power Co. v. United States, 73 F.3d 764 (8th Cir.), cert. denied, 117 S.Ct. 168 (1996), agreed

with this analysis.

Some commentators nevertheless suggest that the regulation under section 6402(a) can be

changed. They point out that the actual statutory language in the Code states that overpayments can

be credited against “any liability.” The word “outstanding” is not used in the statute, and, these

taxpayers argue, it can be deleted from the regulation as well.

The legislative history of section 6402(a) indicates that the regulation provides the correct

reading of the statute, however. The predecessor of section 6402(a), section 322(a) of the Internal

Revenue Code of 1939, provided:

Where there has been an overpayment of any tax imposed by this chapter, the

amount of such overpayment shall be credited against any income, war-profits, or

excess-profits tax or installment thereof then due from the taxpayer, and any balance

shall be refunded. (Emphasis added.)

Authority under this provision was clearly limited to credits against unpaid tax liabilities. Similarly,

section 3770(a)(4) of the 1939 Code, as amended by the Act of August 27, 1949, § 9, 63 Stat. 666,

669, provided that the Commissioner "in his discretion" could, in lieu of refunding an overpayment,

credit such overpayment against any tax due from the taxpayer. Congress did not change these rules
- 30 -

when section 6402(a) was enacted in 1954. It merely added interest on the overpayment to the

amount that could be credited to any outstanding liability.

Moreover, implementing global netting through the credit/offset approach under existing law

would require a strained reading of section 6402(d), particularly in light of its purpose. That

provision permits an overpayment to be credited against another liability in lieu of refunding the

overpayment. In this context, it seems unreasonable to interpret “liability” to mean -- solely for

purposes of computing interest on a prior underpayment under section 6601 -- a tax liability that has

already been satisfied. 

This view is supported by Northern States Power Co. v. United States, 73 F.3d 764 (8th Cir.),

cert. denied, 117 S.Ct. 168 (1996), the only case to address this issue directly. The court there

concluded that the term "liability" as used in section 6402(a) meant "outstanding" liability, relying not

only on the existing regulation but also on its reading of the entire statutory scheme, including section

6601(f), the interest netting rule that applies if a credit or offset is made under section 6402(a):

We agree with the United States that the word "liability" in Section 6402

means "outstanding liability," one that is unpaid when the credit is made. The

Treasury regulations support this reading, see C.F.R. § 301.6402-1 (referring to an

"outstanding liability"), and we properly defer to these regulations.... This is also the

reading that makes the most sense, because only an outstanding liability can be

"satisfied" by a credit. See I.R.C. § 6601(f). NSP provides no support, other than

a strained reading of miscellaneous bits of legislative history, for its assertion that

Section 6402(a) is somehow "time-neutral," that a "liability" may be one that no

longer exists, but once did. We think this argument withers before the statute's plain

meaning. We are likewise not convinced by NSP's attempt to read the word

"outstanding" out of the relevant Treasury regulation, 26 C.F.R. § 301.6402-1. In

our view, the regulation means what it says. (Emphasis added.)

Like section 6402(a), section 6601(f) is apparently intended to apply only when an

outstanding liability is satisfied by the application of an overpayment. As the court in Northern States

Power noted, the phrase “if any portion of a tax is satisfied by credit of an overpayment”

contemplates that the tax against which the overpayment is credited has not been satisfied until the

credit is made -- or in other words that it is an unpaid, outstanding liability at the time of the credit.

Congress would not have referred to the “satisfaction” of a liability that was already fully paid. 

On the other hand, the overall intent of section 6601(f) is to eliminate interest to the extent

there is mutuality of indebtedness between the taxpayer and the Government. For example, the

legislative history of that provision states: 

Under present law situations can arise where, even though underpayments and

overpayments offset each other, the Internal Revenue Service collects more interest

than it pays or the taxpayer is entitled to more interest than he owes the Government.
- 31 -

* * *

The House bill eliminates these erratic differences of present law by

terminating the interest both as to the overpayment and underpayment during any

period of time to the extent they offset each other, except that interest on a deficiency

will be charged for any period during which interest on the overpayment would not

have been allowed if the overpayment had not been credited against the deficiency.

S. Rep. No. 1983, 85th Cong., 2d Sess. 97-100 (1958), reprinted in 1958-3 C.B. 1020-21. Although

Congress was not referring to the interest rate differential (which was not enacted for nearly 30

years), this language indicates that Congress was concerned with the ability of the government to

collect more interest than it pays during periods of mutual indebtedness -- generally an analogous

situation. As the U.S. Court of Claims stated in Fruehauf Corp. v. United States, 477 F.2d 568, 572

(1973):

The evil at which the statute was aimed was the disparate running of interest on

overpayments and underpayments, and the remedy provided by the Act was

termination of the interest on both during any period of time to the extent that they

offset each other.

But the Technical Explanation in the Senate Report makes clear that the operation of section

6601(f) depends on actual crediting of overpayments:

Interest on a credited overpayment would in either case now run only from the date

of the overpayment to the original due date of the amount against which it is credited.

Thus, if it is credited against an underpayment antedating the overpayment, no interest

would run on the overpayment at all. Since interest would otherwise run on the

overpayment from the date of the overpayment to the date of the refund, interest on

the underpayment will stop running as of the date of the overpayment; that is, when

the mutuality of indebtedness arises. Similarly, in the case of an overpayment that

antedates the due date of the underpayment, interest will run on the overpayment only

until such due date, that is, when the mutuality of indebtedness arises. 

S. Rep. No. 1983, 85th Cong., 2d Sess. 234-35 (1958), reprinted in 1958-3 C.B. 1156 (emphasis

added). Fruehauf likewise does not support global netting because that case did not involve the

application of an overpayment to a previously paid underpayment.

B. Interest Equalization Approach

The interest equalization approach does not rely on actual or deemed credits or offsets.

Rather, the concept is that interest rates are equalized, i.e., no net interest is charged in either

direction, to the extent that there are periods and amounts of overlapping mutual indebtedness
 Of course, in the credit/offset situation section 6601(f) ultimately works to equalize the 7/

interest rates as well. But under the interest equalization model there is no actual crediting of

funds against each other in order to achieve the section 6601(f) result.

- 32 -

between the Government (owing a taxpayer a refund) and a taxpayer (owing the Government a

deficiency). This approach forms the basis for annual netting, as set forth in Rev. Proc. 94-60, 1994-

2 C.B. 774, and is similar to a proposed revenue procedure submitted to the IRS by the

Commissioner’s Advisory Group as part of the IRS’s earlier efforts at addressing the interest rate

differential problem. Several commentators in this study suggested that the proposed revenue

procedure could form an appropriate way to extend interest equalization to the global netting

situation.

The proposed revenue procedure, which was not adopted by the IRS, describes how interest

on an underpayment or overpayment should be calculated by the IRS during periods of mutual

indebtedness. Mutual indebtedness is generally any period of time during which the taxpayer owes

money to the Government and the Government owes money to the taxpayer. In order to adjust for

the interest rate differential, the tax accounts are netted by paying or crediting to the taxpayer a "rate

equalization amount" for the period of mutual indebtedness. The “rate equalization amount” is

equivalent to the interest rate differential for the period and amount of mutual indebtedness.

The interest equalization approach thus does not rely on the IRS’s authority to make credits

pursuant to section 6402(a) or on the “satisfaction” of a tax liability under section 6601(f). Rather, 7/

utilizing the rate equalization computation, a taxpayer would simply be charged less underpayment

interest (or paid more overpayment interest) to effectively equalize the interest during any period of

mutual indebtedness. Therein lies the problem, however, for interest equalization cannot be

implemented in a multi-year (global netting) situation under current law. Under the current Code

provisions, sections 6601 and 6611 set forth the periods for which interest is computed and refer to

section 6621 for the interest rates to be used. Section 6601 clearly requires that interest on an

underpayment shall be paid "at the underpayment rate established under section 6621." Likewise,

section 6611(a) clearly provides that interest on an overpayment "shall be allowed and paid upon any

overpayment . . . at the overpayment rate established under section 6621" (emphasis added). Section

6621(a) is similarly mandatory: it states that the overpayment and underpayment interest rates “shall”

be those shown in that provision. In short, no interest rates, other than those set forth in section

6621, are authorized for interest computation purposes. 

While the general purpose of an interest equalization method is to net interest during a period

of mutual indebtedness, the netting is ultimately accomplished by reducing the amount of

underpayment interest below the rate set by section 6621, or by paying more overpayment interest

than is allowed under section 6621. This is tantamount to charging or paying interest at an incorrect

rate under the statute. There simply is no authority in sections 6601, 6611, or 6621 permitting this

approach. It is well settled that the government may pay interest only if authorized to do so by a

specific statutory provision. U.S. ex. rel. Angarica v. Bayard, 127 U.S. 251 (1888). 
- 33 -

Under current law, the interest equalization approach would violate this established principle.

Thus, in order for global netting to be implemented using an interest equalization model, Congress

would have to enact authorization to pay or charge interest at a different rate than that set forth in

section 6621 to the extent there are periods of overlapping mutual indebtedness.

Taxpayers have suggested that the interest equalization approach is merely an extension of

Rev. Proc. 94-60, 1994-2 C.B. 774, to multiple year situations. However, the approach taken in Rev.

Proc. 94-60 is legally permissible only because it applies interest equalization in a limited manner for

purposes of computing interest with respect to a single tax year. For any given tax year there

ultimately can be either an underpayment or an overpayment, but not both (although one or the other

may appear to exist at any particular point in time). The method of the revenue procedure is first to

net all adjustments to a single year’s account, determine whether the ultimate balance is an

underpayment or an overpayment, and then apply the appropriate interest rate only to the net

underpayment or overpayment. In the single-year situation it is not necessary to apply another, nonauthorized interest rate to one or more of the accounts in question. Rather, section 6621 is simply

interpreted to apply only to the ultimate, net underpayment or overpayment for the year under

consideration.

The approach of Rev. Proc. 94-60 cannot be extended under existing law to multiple year

situations, however, because for separate tax years there can really be an actual underpayment for one

year and an actual overpayment for the other year. If an (outstanding) underpayment and an

(outstanding) overpayment exist for two different tax years, then interest netting can take place under

current law only if the underpayment is satisfied by crediting of the overpayment, pursuant to sections

6402(a) and 6601(f). By contrast, the single-year situation does not involve the application of those

provisions.

The only way to allow interest equalization over multiple years and taxes would be to

interpret “underpayment” or “overpayment” as broadly in the multi-year context as it is in the singleyear context covered by Rev. Proc. 94-60. Some commentators have suggested this, arguing that

global netting could be accomplished by taking several years of tax liabilities, netting them all

together, determining whether the taxpayer is in a net under- or overpayment position for all those

years, and then applying the appropriate interest rate under section 6621 to the multi-year balance.

This, however, violates the clear statutory concept that each tax year is a separate and distinct

liability, with only limited exceptions expressly provided in the Code. The commentators who have

suggested this methodology fail to cite any legal authority for treating multiple years as a single

underpayment or overpayment with a net balance.

Limitations period considerations

As noted earlier, some commentators suggested that global netting should be allowed for

interest accruing after December 31, 1986 for all years, whether open or closed, to the extent

necessary to compute interest accurately for a refund or an assessment in an open year. The periods
- 34 -

of limitation applicable to claims for refund create a substantial legal restriction on the Government's

ability to achieve global netting, however.

In general, the amount of any tax must be assessed within 3 years after a return is filed

(whether or not the return is filed on the date prescribed). IRC § 6501. The Secretary and the

taxpayer may agree to extend the period of limitation on assessment by written agreement entered

into prior to the expiration of the period of limitation. IRC § 6501(c). Interest on underpayments

prescribed under section 6601 may be assessed and collected at any time during the period within

which the tax to which such interest relates may be collected. IRC § 6601(g).

Claims for credit or refund of an overpayment, on the other hand, generally must be filed

within 3 years from the time the return was filed or 2 years from the time the tax was paid, whichever

period expires later. IRC § 6511(a). If the parties agree to extend the period of limitations on

assessment, see IRC § 6501(c)(4), then the period of time for filing a claim for credit or refund

generally will not expire prior to 6 months after the expiration of the extended period. IRC

§ 6511(c).

No credit or refund can be allowed or made after the expiration of the applicable period of

limitations unless a claim for credit or refund is filed by the taxpayer within such period. IRC

§ 6511(b)(1). In particular, section 6511(b)(2)(A) provides that if the claim is filed within the 3-year

period, the amount of the credit or refund shall not exceed the portion of the tax paid within the

immediately preceding 3-year period plus any extension of time to file, and section 6511(b)(2)(B)

provides that if the claim is not filed within the 3-year period, the amount of the credit or refund shall

not exceed the amount of tax paid within the 2-year period immediately preceding the filing of the

claim. If a taxpayer pays interest on a deficiency and it is later determined that the taxpayer is not

liable for the deficiency, the amount of the underpayment interest previously paid by the taxpayer is

considered part of the overpayment subject to the period of limitations set forth in section 6511. See

Treas. Reg. § 301.6611-1(c). Again, these rules are mandatory. Refunds made in violation of them

are considered erroneous, and credits made in violation of them are considered void. IRC § 6514(a).

These periods of limitation on refunds create a legal impediment to the adoption of global

netting. This is easily demonstrated by the following example. Assume that a taxpayer files an

income tax return for 1990 on April 15, 1991, and an underpayment is ultimately determined and paid

on April 15, 1993. Interest at the underpayment rate is charged and paid on the underpayment for

the period from April 15, 1991 to April 15, 1993. Assume further that the same taxpayer files an

income tax return for 1991 on April 15, 1992. A claim for refund is then filed on April 15, 1994,

requesting a refund for 1991. The claim is allowed and a refund with interest is paid on October 15,

1995. The taxpayer realizes in retrospect that the interest rate differential on the 1990 underpayment

could have been partly avoided if the 1991 overpayment had been taken as a credit against the 1990

underpayment instead of having been refunded. Therefore, on April 15, 1996, the taxpayer asks the

IRS to apply the 1991 overpayment as a credit to the 1990 tax liability solely for interest computation

purposes.
- 35 -

In this example, the period of limitation on claims for refund prohibits the IRS from refunding

any portion of the interest paid on the 1990 underpayment, since any claim for refund with respect

to interest paid for that year should have been filed on or before April 15, 1995 (two years from the

date of payment). See IRC § 6511; Treas. Reg. § 301.6611-1(c); Alexander Proudfoot Co. v. United

States, 354 F. 2d 1379 (Ct. Cl. 1972) (claims for refund of deficiency interest must be filed within the

period specified in section 6511). Further, if the IRS did refund the portion of the interest equal to

the differential rate, such amount would be a statutory erroneous refund. See IRC § 6514(a).

A similar problem also exists under the interest rate equalization approach. Although the

interest rate equalization approach does not employ actual or deemed tax credits, the period of

limitation for filing a claim for overpaid deficiency interest must still be open at the time the

overpayment is determined. In the example above, a claim for refund of the interest differential paid

for the period from April 15, 1992, to April 15, 1993 must be filed by April 15, 1995. However, in

this case the existence of the 1991 overpayment, which is a necessary element of the period of mutual

indebtedness, is not determined by the IRS until October 15, 1995, which is after the period of

limitation has expired with respect to the 1990 tax year.

In short, existing limitations provisions present obstacles to netting, irrespective of whether

a credit/offset approach or an interest equalization approach is used. 
- 36 -

ADMINISTRATIVE ISSUES INVOLVED IN INTEREST NETTING

This section will first describe the IRS’s current administrative procedures relating to interest

computations for annual interest netting and offsetting. It will then describe what new procedures

and additional resources would be required to expand these procedures to perform global interest

netting computations. 

Annual netting

The simplest case in which interest netting becomes an issue involves a single tax year for a

taxpayer, in which a refund with overpayment interest has been issued and a subsequent deficiency

is assessed with respect to the same year, so that underpayment interest is due. See Rev. Proc. 94-60,

§ 1, 1994-2 C.B. 774. The question is whether interest at the higher, underpayment rate should be

imposed on the deficiency for the period for which overpayment interest (at the lower, overpayment

interest rate) was previously paid. Ordinarily, section 6601(a) would require that the higher,

underpayment interest rate under section 6621 be applied to the full amount of the deficiency for the

full amount of time since the tax became due, and the taxpayer would not get any benefit of netting.

Pursuant to Rev. Proc. 94-60, however, for the period for which the taxpayer was already paid

overpayment interest on the excessive tax refund, the IRS will collect interest at the same (lower,

overpayment) rate, not the underpayment rate, on the portion of the tax underpayment that does not

exceed the excessive tax refund. Rev. Proc. 94-60, § 3, 1994-2 C.B. at 775.

The IRS performs annual interest netting two ways. In simple cases, the IRS’s Master File

system will calculate netted interest automatically when the Rev. Proc. 94-60 criteria apply to a

taxpayer’s module. The interest computations in such cases do not require any manual calculation,

and therefore no additional resources are needed to implement Rev. Proc. 94-60. This automatic

computation is also highly accurate and reliable.

Even for annual interest netting, however, many cases require manual computations of interest

that cannot be performed systemically. There are two related reasons for this: the legal requirements

of the computations and the computer capabilities necessary to take all such legal requirements into

account. 

The legal requirements relate principally to the starting and ending dates that are part of the

interest computation. The Code contains several special provisions that require starting an interest

computation from a date other than the normal due date of the return. E.g., IRC §§ 6601(b),

(e)(2)(A); 6611(d),(f), (g). Likewise, the ending date for interest computations in many situations

is not the same as the date of the final adjustment to a tax account. E.g., IRC §§ 6601(d)(1),

(d)(2)(A). Most of these provisions relate to penalties and carrybacks from other tax years. Quite

apart from the effects of offsetting in multi-year situations, these special rules can require annual

netting with respect to a specific tax year whenever multiple years of the taxpayer are open.
 This section will be renumbered as IRM (22)000, entitled “Interest,” in 1997. 8/

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The IRS’s Master File system, which was designed to track and store taxpayer account

activity, cannot accommodate and manipulate all the possible combinations of these special starting

and stopping dates for complex interest computations. The simpler computations with “regular”

starting and stopping dates can be performed on the Master File, but the more complex cases require

review and calculations by a trained specialist.

To the extent manual computations of annual interest netting are required, the calculations

may be performed by various IRS employees depending on the nature and complexity of the

adjustments. The computations are generally made by processing technicians in connection with

entering the adjustment to the taxpayer’s account. Since adjustments can arise due to amended

returns, audits, Appeals decisions, collection actions, court decisions, etc., the interest computations

may be performed at IRS Service Centers, District Offices, or Appeals Offices. 

The procedures for annual interest netting are set forth in IRM 31(59)0, an excerpt from

which is enclosed as Appendix Four. Briefly, the general interest computation procedure requires 8/

the technician to analyze the transactions on the taxpayer’s account, identify which transactions affect

the interest computation, and then determine the appropriate interest starting and stopping dates and

interest rates to be applied. In particular, annual interest netting requires determining the period(s)

of time for which overpayment interest was previously paid, and then calculating underpayment

interest at the overpayment rate on the refunded amount for such period(s).

The technician performs the analysis using a transcript of the taxpayer’s account and the

report of any adjustments that are being, or have been, made. Data from those sources that are

needed for the interest computation are input into a separate computer program that is not part of the

IRS’s Master File system for tracking taxpayer accounts. Technicians must be familiar not only with

the interest rules in the Code, regulations, and Internal Revenue Manual, but also with the nuances

of the Master File, the IRS’s Non-Master File system, and the stand-alone interest computation

computer programs. After the calculations are performed off-line, the net interest amount is entered

as a separate adjustment on the taxpayer’s Master File account. Because of the special conditions

that required manual interest computations in the first place, a special code is entered with the net

interest adjustment to prevent the computer from erroneously making automatic adjustments to that

account in the future. Thereafter, any future interest computations that involve that tax year must

also be performed manually. 

Offsetting

Offsetting arises whenever an overpayment is determined with respect to one tax year (or

liability) and may be applied to an outstanding liability for another year pursuant to section 6402(a).

As discussed above, there is a special interest computation rule for such situations, section 6601(f)

of the Code. As this rule operates, if an overpayment is actually applied against an underpayment,

interest is calculated only on the net outstanding balance for the period (and amount) of the overlap.
- 38 -

In effect, therefore, both the underpayment and overpayment interest rates for the overlapping period

and offsetting amount are zero. Interest is charged (or paid) only on the net balance.

By law, an offsetting situation involves at least two unsettled tax accounts, one an

overpayment and one an underpayment. As with annual interest netting, offsetting is performed both

systemically by the IRS computers and manually by technicians. The Master File is programmed to

search for outstanding liabilities (tax-due accounts) for the same taxpayer whenever it shows a credit

(overpayment) available for that taxpayer. This search is performed every time an overpayment

arises, whether for individual or business taxpayers, literally millions of times each year.

Whenever an offset can be systemically performed, the Master File system also computes the

appropriate interest on all the affected accounts, in accordance with the special rule of section

6601(f). The taxpayer in such a situation will receive a statement explaining the adjustments,

including the interest computation. Again, in such situations, the interest computations do not require

any manual calculation or additional resources, and the computations are routinely accurate and

reliable based on the information on record.

However, there are frequently conditions under which an offset cannot be systemically

performed. Many of these conditions relate to the same kinds of legal issues that prevent automatic

annual netting, such as the applicability of restricted interest rules with special interest starting and

ending dates. Other situations include the bankruptcy of the taxpayer or statutes of limitations that

are about to expire.

Offsetting frequently arises in extremely complex cases involving multi-year audits for large

corporations. In such cases there may be numerous adjustments to each account, some issues that

are agreed and others that are unagreed, partial tax payments or refunds, and many resulting periods

of overlapping indebtedness. These cases, which present the greatest challenges in calculating

interest, almost always involve one or more of the conditions that require the calculations to be done

manually rather than by the computer system. 

Although offsetting interest computations use essentially the same procedures that were

described above for annual interest netting, there are additional layers of complexity at each step due

to the fact that more tax periods and transactions are at issue. Simply performing the analysis

requires a sophisticated understanding of all the adjustments that may be made to the taxpayer’s

account under the Code, such as the carryforward and carryback rules and the restricted interest

rules, as well as familiarity with the IRS’s various computer systems. The analysis and computations

in offsetting cases are thus usually performed by GS-8 and GS-9 technicians who are assigned the

most complex interest calculations.

Performing offsetting interest calculations can take a significant amount of time for even the

best-trained IRS personnel. Gathering the data, performing the necessary legal and computational

analysis, and actually running the computations can frequently take a technician 40 to 80 hours for

a single case. The time is even greater in certain situations, where for example necessary back-up
- 39 -

documentation for previous manual adjustments to the accounts is not available. If such back-up data

are missing, it can be virtually impossible to reconstruct earlier manual interest computations.

Global netting

From a conceptual point of view, global netting would largely be the same as offsetting, with

one significant difference. Offsetting can only occur when all tax periods at issue still have an

imbalance (underpayments or overpayment) outstanding, but global netting would additionally involve

tax years that have no outstanding underpayments or overpayments, i.e. balances of zero.

Although the methodology applied for global netting would be basically the same as for

offsetting, the addition of zero-balance years would substantially increase the amount of data that

must be gathered and analyzed. Further, data on zero-balance years is much more difficult to obtain

due to the IRS’s document retention practices. For example, because of the limited data storage

capacity of the IRS’s Master File, the IRS must routinely archive data for inactive accounts. It takes

an account “off-line” shortly after it is fully paid (i.e., in a zero balance), moves the account to a lower

level of storage after a couple years of inactivity, and eventually moves it to archives. Further, only

certain key data elements are sent to the archives, and those elements are insufficient to perform

global interest netting calculations.

In addition to the information on the Master File for a particular taxpayer, the tax returns and

back-up documentation for previous computations must be obtained before a new netting

computation can be performed. For example, to perform a global interest netting computation for

a large corporate taxpayer, a technician would need the return and supporting schedules, current

transcripts, the Revenue Agent’s Report and related workpapers, previous interest computation

worksheets and Forms 2285 (“Restricted interest on concurrent determinations of deficiencies and

overpayments”), any pertinent court decisions, settlement memoranda, Appeals audit statements, and

similar documents. For older, zero-balance years, this information is frequently unavailable or

incomplete.

If all of this documentation were available, the time required for the analysis in a multiple year

global netting computation would still be extensive. By comparison, a multiple year manual offsetting

case, which is substantially simpler than a global netting case, takes an IRS technician one to two

weeks to perform. Even when a taxpayer provides the documentation for prior tax years, the effort

can be enormous, as one commentator candidly stated:

The time involved in reviewing the source documents so as to glean all of the

necessary underlying facts can range from 40 to 600 hours. In the usual case of a

large corporate taxpayer, 300 to 400 man-hours typically would be required to

complete the review and computations.
- 40 -

Comments of KPMG Peat Marwick LLP (June 30, 1996) at 37. Moreover, as with any computation

of this complexity, the possibilities for error expand dramatically. Mistakes are more likely, and

consequently more double-checking and review is needed to eliminate mistakes. 

Taxpayers have argued that the time required to do global netting computations would be

considerably less because the taxpayers themselves would do most of the work and the IRS would

only have to verify the calculations. Indeed, the same commentator quoted above stated:

The IRS would only incur a fraction of this cost, because it only would have to review

the accuracy of the taxpayer’s calculations. 

Id. While taxpayers can undoubtedly assist in accumulating data, especially for zero-balance years,

it would be irresponsible for the IRS to accept a taxpayer’s computations and pay the taxpayer’s

claim without verifying both the data and the calculations that form the basis for the claim. In

particular, such items as the effects of carrybacks and carryforwards and the appropriate starting and

stopping dates for interest under various circumstances require significant independent analysis and

are often subject to varying legal interpretations.

The IRS currently does not perform global interest netting because of its position that it lacks

the legal authority to do so. In addition, the calculations are considerably more complex than

multiple-year offsetting cases because the addition of the zero-balance years vastly increases the

universe of possible legal issues that must be analyzed and the interest rules that must be considered

for their effect on open tax years that require adjustment. As discussed above, the IRS has limited

data storage capacity on its Master File and documentation in case files for zero-balance years is often

incomplete or unavailable. The lack of data for zero-balance years on the Master File and the limited

ability of the Master File to manipulate data for the complex calculations required for global interest

netting prevents the IRS from performing such calculations on its Master File. Therefore, the IRS

would have to spend significant resources to gather and analyze the data necessary to make global

interest netting calculations and input the data into a stand-alone interest computation program. For

these reasons, the IRS has determined that, apart from the legal restrictions on global interest netting

discussed above, such computations would be highly problematic administratively.

Making global netting feasible

The IRS recognizes that Congress has repeatedly instructed it to implement the most

extensive interest netting procedures possible, consistent with sound administrative practice and the

various provisions of the Code. E.g., H.R. Conf. Rep. 841, 99th Cong., 2d Sess. II-785 (1986),

reprinted in 1986-3 C.B. (Vol. 4) 785; H.R. Conf. Rep. No. 964, 101st Cong., 2d Sess. 1101 (1990),

reprinted in 1991-2 C.B. 591; H.R. Rep. No. 826, Part I, 103d Cong., 2d Sess. 178 (1994), reprinted

in 1995-1 C.B. 254. If the legal issues presented by global interest netting are resolved by Congress

through enactment of express statutory authority, the IRS believes that it can implement global

interest netting fairly and equitably only if certain limitations are provided.
 The total on the 23rd page of calculations did not tie with the first line of page 24 (a one- 9/

day difference accounted for the discrepancy), although the rest of the example reflected the

correct number. To its credit, the commentator brought this minor discrepancy to the IRS’s

attention after the hearing and promptly provided a corrected example.

- 41 -

Even with these limitations, however, global interest netting calculations will involve

significant administrative complexity. This potential complexity is illustrated by an example that one

commentator submitted at the public hearing on global interest netting held by IRS and Treasury on

September 4, 1996. The commentator submitted the example to illustrate how simple global interest

netting would be to administer, and yet it is approximately 25 pages long, most of which would

require extensive manual data inputting. The example contains no tax years barred by statute, and

no partial payments or credits on any of the years, which are frequent for corporate taxpayers and

which complicate interest calculations significantly. The commentator’s initial presentation of this

example contained a minor presentation error, which illustrates the need for IRS to check the

9/

computations. Most importantly, the assumptions of the example implicitly ignore the most

problematic issue with global interest netting -- the collection of the data necessary for an accurate

calculation. As noted previously, global interest netting requires extensive documentation for all tax

years that will be a part of the calculation, but such information is not always available or complete.

In light of the administrative difficulties associated with global netting, Treasury and the IRS

believe that such netting should be authorized by Congress only if the following limitations are

adopted. First, global interest netting should be implemented legislatively through an interest

equalization approach, rather than through a credit/offsetting approach. The legislation would

provide for interest equalization (or a net interest rate of zero percent) to the extent taxpayers and

the IRS have overlapping periods and amounts of mutual indebtedness (i.e., taxes or refunds due).

Under this approach, global interest netting would require at least one non-zero-balance tax year to

be taken into account in the computation. 

An interest equalization model should be substantially easier for the IRS to administer and

should allow the IRS to adjust taxpayer accounts in a manner consistent with existing procedures.

Many commentators and IRS personnel believe that using a credit/offset model, by contrast, could

improperly create new liabilities in zero-balance accounts, with corresponding difficulties that could

result in incorrect notices being sent to taxpayers and erroneous collection activity.

Second, global interest netting should be limited to income taxes only. Congress apparently

contemplated a restriction of this sort when interest netting was first discussed in 1986. See S. Rep.

No. 313, 99th Cong., 2d Sess. 185 (1986), reprinted in 1986-3 C.B. (Vol. 3) 185 (IRS should net

underpayments and overpayments “for the same type of tax” in different years). Allowing global

netting across different kinds of taxes would be extremely difficult to administer and would

substantially increase the amount of IRS resources that would need to be devoted to make such

calculations. For example, the largest companies make employment tax deposits on a daily basis, and

only a part of such deposits constitute the employer’s portion of the taxes to which netting could

apply (the other parts include employee withholding and the employees’ portion of employment
- 42 -

taxes). Similarly, excise taxes frequently present difficult questions concerning who has paid them

or whether they have been passed on to other taxpayers.

Global interest netting for different kinds of taxes would vastly increase the amount of data

that would need to be located, gathered, analyzed, and entered into a calculation. The data would

have to be manually input, and because interest is compounded daily the computations could become

very complex, with a corresponding increase in the probabilities of errors or disagreements with the

taxpayer over the calculations. As a result, global netting across different types of taxes should not

be required.

Third, global netting should apply only to tax years that are not barred by statute. There are

compelling reasons for both taxpayers and the IRS to favor finality, and large amounts of money and

time are expended to reach finality for past tax years. Since the principal amounts of underpaid or

overpaid taxes in barred years are not considered in adjusting taxpayers’ other tax year accounts, it

makes little sense to consider the interest that was charged or paid on those underpayments or

overpayments. Taxpayers who are concerned about the interest rate differential may extend the

statutes of limitations for assessments, even with respect to tax years that have a zero balance, in

order to preserve the chance of global interest netting. Conversely, it makes little sense to reopen

statutorily-barred years because of an interest netting computation unless they are also opened for

reconsideration of other, substantive tax issues -- a result that many taxpayers would not want. 

The administrative difficulties of including barred years in the computations are also

substantial. Limitations on computer and other storage capacity means that the IRS retains little data

on barred years, and in particular may not be able to reconstruct previous interest adjustments that

were made in such years.

Fourth, the IRS should only perform global interest netting calculations at a taxpayer’s

request, and the taxpayer should bear the burden of demonstrating entitlement to any netted interest

amount claimed. The taxpayer’s request should supply the IRS with all relevant documentation and

a copy of the taxpayer’s calculations. Providing such documentation and calculations will assist the

IRS in verifying the accuracy of the calculations, thus significantly shortening the time needed to

process the request.

In particular, global netting should ordinarily be performed only once with respect to the

account for any tax year, because once an account has been considered in a global netting calculation,

the actual netted interest amount due is entered as a single adjustment to the taxpayer’s account.

That final adjustment would not be further adjusted unless the taxpayer provided explicit

documentation to back up any changes (including every underlying document for the prior interest

calculation).

Most of these suggested restrictions (other than the first one) could be implemented by

regulations if Congress enacts a global netting provision using an interest equalization approach. As

a further condition for global netting, therefore, authority to prescribe regulations in these areas
- 43 -

should be granted to Treasury. The regulations would be expected to reflect the restrictions

suggested above.

Finally, to the extent global interest netting requires additional personnel and resources,

Congress should make adequate appropriations to fund the additional costs that the IRS will bear.

Because of the administrative difficulty of global netting and the additional resources needed to

implement it (including training and new personnel), a phase-in period of approximately two years

should be provided.
- 44 -

CONCLUSION AND RECOMMENDATIONS

There is a tension between the imposition of interest rate differentials for overpayments and

underpayments and the desire to allow interest netting in situations of mutual indebtedness. Congress

has not clearly expressed its preference between these goals, particularly in the global netting

situation. Although Congress has increased the interest differential several times in the past decade,

it has simultaneously urged expanded interest netting each time it has done so. 

This contradiction is reflected in the fact that Congress has never provided the clear statutory

authority that is necessary to implement true global interest netting nor clarified the policy

justifications for it. It makes little sense, however, for interest netting to be available in some

situations (i.e., offsetting or annual netting) but not in others (the global netting situation). Resolving

the policy issues and providing unambiguous legal authority for global interest netting would

complete Congress’s efforts in this area.

So long as Congress adheres to the policy goal of the most comprehensive interest netting that

is administratively feasible to implement, it makes sense to provide specific statutory authority for

netting in all cases, including the true global netting situation. Accordingly, the Department of the

Treasury recommends that Congress enact clear statutory authority for global interest netting, using

an interest equalization approach and subject to the other limitations discussed in the previous section,

which are necessary to make global netting administratively feasible. Treasury and the IRS are

prepared to work with the tax-writing committees of Congress to enact this legislation.
APPENDIX ONE

Notice 96-18, 1996-14 I.R.B. 27 (April 1, 1996).
- 46 -
- 47 -
APPENDIX TWO

Persons submitting comments in response to Notice 96-18. 

The following persons or entities submitted comments to the IRS in response to Notice 96-18,

1996-14 I.R.B. 27 (April 1, 1996). 

American Bar Association

American Gas Association

American Institute of Certified Public Accountants

Dresser Industries, Inc.

Edison Electric Institute

Ernst & Young LLP

Financial Executives Institute

KPMG Peat Marwick, LLP

New York Clearing House

Price Waterhouse LLP

Tax Executives Institute, Inc.

Marshall W. Taylor, Esq., Taylor, Simonson & Winter
APPENDIX THREE

Witnesses at hearing September 4, 1996.

A hearing was held on September 4, 1996, in Washington, D.C., pursuant to section

1208(a)(2) of TBOR 2 and Announcement 96-75, 1996-34 I.R.B. 29. The following persons testified

at that hearing: 

Mark H. Ely, representing KPMG Peat Marwick, LLP

Jim Crook, representing Caterpillar Inc., and Eileen Reiger, representing Price Waterhouse

LLP

Kathy Everidge, representing Ernst & Young LLP

Robert L. Ashby, representing Tax Executives Institute, Inc.
APPENDIX FOUR

Excerpt from IRM 31(59)(31).
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