<PAGE>


                          FIRST AMENDMENT TO UNSECURED
                           REVOLVING CREDIT AGREEMENT

     THIS FIRST AMENDMENT TO UNSECURED REVOLVING CREDIT AGREEMENT (this
"Amendment") is made as of the 21st day of December, 2001, by and among STORAGE
USA FRANCHISE CORP., a Tennessee corporation ("Borrower"), SUSA PARTNERSHIP,
L.P., a Tennessee limited partnership (the "Operating Partnership"), STORAGE
USA, INC., a Tennessee corporation (the "General Partner"), STORAGE USA TRUST, a
Maryland business trust (the "Trust"; the Operating Partnership, the General
Partner and the Trust being hereinafter referred to collectively as the
"Guarantors"), FIRST UNION BANK, individually ("FUNB") and as administrative
agent (the "Agent") for the Lenders (as defined in the Credit Agreement referred
to below).

                                    RECITALS.
                                    --------

     WHEREAS, Borrower, Guarantors, Agent and FUNB entered into that certain
Unsecured Revolving Credit Agreement, dated as of December 29, 2000 (the "Credit
Agreement"); and

     WHEREAS, Operating Partnership, General Partner, and the Trust executed and
delivered that certain Guaranty, dated as of December 29, 2000, in favor of
Agent and the Lenders (the "Guaranty"); and

     WHEREAS, Borrower has requested that the Lenders modify the Credit
Agreement to extend the maturity date thereof pursuant to the terms of this
Amendment; and

     WHEREAS, as a condition to such modification, Agent and the Lenders have
required that Borrower and the Guarantors execute this Amendment;

     NOW, THEREFORE, for and in consideration of the sum of Ten and No/100
Dollars ($10.00), and other good and valuable considerations, the receipt and
sufficiency of which is hereby acknowledged, and in consideration of the
recitals herein and the mutual covenants contained herein, the parties hereto do
hereby covenant and agree as follows:

     1. Definitions. All terms used herein which are not otherwise defined
herein shall have the meanings set forth in the Credit Agreement.

     2. Modification of the Credit Agreement. Borrower, Guarantors, the Lenders
and Agent do hereby amend and modify the Credit Agreement as follows:

        (a) By amending the definition of the term "Facility Termination Date"
set forth in Article I of the Credit Agreement, appearing on page 6 thereof, by
deleting therefrom the date "December 29, 2001" and inserting in lieu thereof
the date "December 29, 2002."

        (b) By deleting the definition of "Operating Partnership Credit
Agreement" set forth in Article I, appearing on page 9 thereof, and inserting
in lieu thereof the following new definition:

<PAGE>

                           "Operating Partnership Credit Agreement" means that
                           certain Third Amended and Restated Unsecured
                           Revolving Credit Agreement dated as of September 17,
                           2001, among the Operating Partnership, the General
                           Partner, the Trust, First Union National Bank, the
                           other lenders a party thereto, and Bank One, N.A. as
                           Administrative Agent."

     (c) By deleting ss. 8.7 of the Credit Agreement, appearing on page 35
thereof, and inserting in lieu thereof the following new ss. 8.7:

                           "8.7 Merger. The Operating Partnership, the General
                           Partner and the Borrower will not, nor will they
                           permit any of their Subsidiaries to, enter into any
                           merger, consolidation, reorganization, liquidation or
                           other business combination or transfer or otherwise
                           dispose of all or a Substantial Portion of its
                           Properties or agree to effect any stock acquisition,
                           asset acquisition or other acquisition, except for
                           such transactions that occur between Wholly-Owned
                           Subsidiaries of the Borrower or as otherwise approved
                           in advance by the Lenders, provided, however, that
                           mergers shall be permitted as a means for the
                           Borrower or a Subsidiary of the Borrower to acquire
                           additional Storage Properties or ancillary businesses
                           reasonably related to Storage Properties so long as
                           such merger is not accomplished through a hostile
                           takeover and the Borrower is the surviving entity."

     3. Amendments to Loan Documents. The Borrower and Guarantors shall
contemporaneously with the execution of this Amendment enter into such
amendments to the other Loan Documents as Agent may request to evidence the
amendment to the Credit Agreement set forth herein. Additionally, Borrower
agrees to pay all reasonable fees, expenses and disbursements of counsel to
Agent incurred in connection with the preparation of this Amendment and the
modification of any other Loan Documents in connection therewith.

     4. References to Credit Agreement. All references in the Loan Documents to
the Credit Agreement shall be deemed a reference to the Credit Agreement as
modified and amended herein.

     5. Consent of Guarantors. By execution of this Amendment, Guarantors hereby
expressly consent to the modifications and amendments relating to the Credit
Agreement as set forth herein including, without limitation, the amendment to
the definition of "Facility Termination Date" contained in the Credit Agreement,
and any amendments of the Loan Documents executed contemporaneously herewith,
and Borrower and Guarantors hereby acknowledge, represent and agree that the
Loan Documents (including without limitation the Guaranty) shall remain in full
force and effect after giving effect to the modifications contemplated hereby
and the other documents being executed in connection herewith, and constitute
the valid and legally binding obligations of Borrower and Guarantors,
respectively, enforceable against such Persons in accordance with their
respective terms, and that the execution and delivery of this Amendment and any
other modification documents do not constitute, and shall not be deemed to
constitute, a release, waiver or satisfaction of Borrower's or Guarantors'
obligations under the Loan Documents (including, without limitation, the

                                       2

<PAGE>

Guaranty), and that the Guaranty extends to and applies to the foregoing
documents as modified and amended.

     6. Representations. Borrower and Guarantors represent and warrant to Agent
and the Lenders as follows:

        (a) Authorization. The execution, delivery and performance of this
Amendment and any other amendments of the Loan Documents executed
contemporaneously herewith and the transactions contemplated hereby and thereby
(i) are within the authority of Borrower and Guarantors, (ii) have been duly
authorized by all necessary proceedings on the part of such Persons, (iii) do
not and will not conflict with or result in any breach or contravention of any
provision of law, statute, rule or regulation to which any of such Persons is
subject or any judgment, order, writ, injunction, license or permit applicable
to such Persons, (iv) do not and will not conflict with or constitute a default
(whether with the passage of time or the giving of notice, or both) under any
provision of the partnership agreement or certificate, certificate of formation,
operating agreement, articles of incorporation or other charter documents or
bylaws of, or any mortgage, indenture, agreement, contract or other instrument
binding upon, any of such Persons or any of its properties or to which any of
such Persons is subject, and (v) do not and will not result in or require the
imposition of any lien or other encumbrance on any of the properties, assets or
rights of such Persons, other than the liens and encumbrances created by the
Loan Documents.

        (b) Enforceability. This Amendment and any other amendments of the Loan
Documents executed contemporaneously herewith constitute the valid and legally
binding obligations of Borrower and Guarantors enforceable in accordance with
the respective terms and provisions hereof, except as enforceability is limited
by bankruptcy, insolvency, reorganization, moratorium or other laws relating to
or affecting generally the enforcement of creditors' rights and the effect of
general principles of equity.

        (c) Approvals. The execution, delivery and performance of this Amendment
and any other amendments of the Loan Documents executed contemporaneously
herewith and the transactions contemplated hereby do not require the approval or
consent of or approval of any Person or the authorization, consent, approval of
or any license or permit issued by, or any filing or registration with, or the
giving of any notice to, any court, department, board, commission or other
governmental agency or authority other than those already obtained.

        (d) Outstanding Principal Balance. As of the date hereof, the aggregate
outstanding principal balance of the Loan equals $10,000,000.00.

     7. Status of Loan. By execution hereof, the Borrower and Guarantors certify
that the Borrower and Guarantors are and will be in compliance with all
covenants under the Loan Documents after the execution and delivery of this
Amendment, and that no Default or Event of Default has occurred and is
continuing.

     8. Waiver of Claims. Borrower and Guarantors acknowledge, represent and
agree that Borrower and Guarantors have no defenses, setoffs, claims,
counterclaims or causes of action of any kind or nature whatsoever with respect
to the Loan Documents, the administration

                                       3

<PAGE>

or funding of the Loan or with respect to any acts or omissions of Agent or
the Lenders, or any past or present officers, agents or employees of Agent or
the Lenders, and each of Borrower and each Guarantor does hereby expressly
waive, release and relinquish any and all such defenses, setoffs, claims,
counterclaims and causes of action, if any.

     9. Ratification. Except as hereinabove set forth, (a) all terms, covenants
and provisions of the Credit Agreement, the Guaranty and the other Loan
Documents remain unaltered and in full force and effect, (b) the Agent and the
Lenders hereby insist upon and hereby demand strict compliance by the Borrower
and the Guarantors with all the terms and conditions of the Note, the Guaranty
and the other Loan Documents and (c) the parties hereto do hereby expressly
ratify and confirm the Credit Agreement as modified and amended herein. Nothing
in this Amendment shall be deemed or construed to constitute, and there has not
otherwise occurred, a novation, cancellation, satisfaction, release,
extinguishment or substitution of the indebtedness evidenced by the Note or the
other obligations of Borrower and Guarantors under the Loan Documents (including
without limitation the Guaranty).

     10. Effectiveness. This Amendment shall not be deemed effective and in full
force and effect unless and until this Amendment is executed and delivered by
all parties hereto and all closing conditions have been satisfied, including,
without limitation, the payment by Borrower of all fees of the Lenders in
connection with this Amendment.

     11. Amendment as a Loan Document. This Amendment shall constitute a Loan
Document.

     12. Counterparts. This Amendment may be executed in any number of
counterparts which shall together constitute but one and the same agreement.

     13. Miscellaneous. This Amendment shall be construed and enforced in
accordance with the laws of the State of North Carolina. This Amendment shall be
binding upon and shall inure to the benefit of the parties hereto and their
respective permitted successors, successors-in-title and assigns as provided in
the Loan Documents.



                     [SIGNATURES COMMENCE ON FOLLOWING PAGE]


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<PAGE>

     IN WITNESS WHEREOF, the parties hereto have hereto set their hands and
affixed their seals as of the day and year first above written.

                                         BORROWER:
                                         --------

                                         STORAGE USA FRANCHISE CORP., a
                                         Tennessee corporation

                                         By:
                                            ------------------------------------
                                             Name:
                                                  ------------------------------
                                             Title:
                                                   -----------------------------
                                                       [CORPORATE SEAL]




                                       5

<PAGE>

                                    GUARANTORS:
                                    ----------

                                    SUSA PARTNERSHIP, L.P., a Tennessee limited
                                    partnership

                                    By:   STORAGE USA, INC., a Tennessee
                                          corporation, its General Partner
                                       By:
                                          --------------------------------------
                                          Name:
                                               ---------------------------------
                                          Title:
                                                --------------------------------


                                    STORAGE USA, INC., a Tennessee corporation


                                    By:
                                       -----------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------


                                    STORAGE USA TRUST, a Maryland business
                                    trust


                                    By:
                                       -----------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                        6

<PAGE>

                                    LENDER:
                                    ------

                                    FIRST UNION NATIONAL BANK, Individually
                                    and as Administrative Agent


                                    By:
                                       -----------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       7