<PAGE>
 
                                                                  EXECUTION COPY


          AMENDMENT No. 1, dated as of August 18, 1997 ("Amendment"), to the
CREDIT AGREEMENT, dated as of June 19, 1996 (as the same may be further amended,
supplemented or otherwise modified from time to time, the "Agreement") among
METROMAIL CORPORATION, as borrower (the "Company"), THE FIRST NATIONAL BANK OF
CHICAGO, as Administrative Agent (in such capacity, the "Administrative Agent"),
and the other banks parties thereto (the "Banks").

                             W I T N E S S E T H :
                             -------------------  

          WHEREAS, the parties hereto wish to amend certain provisions of the
Agreement on the terms set forth herein;

          NOW, THEREFORE, in consideration of the premises and of the mutual
agreements herein contained, the parties hereto agree as follows:
 
          1.   Definitions.  Unless otherwise defined herein, terms defined in
the Agreement shall be used herein as so defined.

          2.   Amendments to Section 1.01.

          (i)  The definition of "Termination Date" is amended in its entirety
to read as follows:

          " 'Termination Date' means the earlier of (i) June 19, 2002 or (b) the
     date the Commitments are terminated in whole pursuant to Section 2.05 or
     6.01."

          (ii)  The following new definition is added to Section 1.01, following
the term "Dollars":

          "'Domestic Borrower' means any Borrower that is organized under the
     laws of the United States or any State thereof."

          3.   Amendment to Section 5.18.  Section 5.18(e) of the Agreement is
amended in its entirety to read as follows:

          "(e) Investments in Subsidiaries; provided, however, that Investments
     in Subsidiaries that are not organized under the laws of the United States
     or any State thereof shall not exceed, in the aggregate at any time
     outstanding, twenty-five percent (25%) of the Company's total assets
     determined on a consolidated basis in accordance with GAAP.

          4.   Amendment to Article VII.  Article VII of the Agreement is
restated in its entirety to read as follows:
<PAGE>
 
                                 ARTICLE VII

                                   GUARANTEE
                                   ---------

               SECTION 7.01.  Unconditional Guarantee.  For valuable 
     consideration, receipt whereof is hereby acknowledged, and to induce the
     Banks to make Advances to each of the Borrowers, each Domestic Borrower
     hereby unconditionally guarantees to the Banks and the Administrative Agent
     that the principal of and interest on each Advance and all other amounts
     payable by each other Borrower hereunder shall be promptly paid in full
     when due (whether at stated maturity, by acceleration or otherwise) in
     accordance with the terms hereof and thereof, and, in the case of any
     extension of time of payment, in whole or in part, that all such amounts
     shall be promptly paid when due (whether at stated maturity, by
     acceleration or otherwise) in accordance with the terms of such extension.
     In addition, each Domestic Borrower hereby unconditionally agrees that upon
     default in the payment when due (whether at stated maturity, by
     acceleration or otherwise) of any of such principal, interest or other
     amounts, such Domestic Borrower shall forthwith pay the same. Without
     limiting the generality of the foregoing, each Domestic Borrower's
     liability shall extend to all amounts that constitute part of the
     obligations of any other Borrower guaranteed under this Article VII and
     that would be owed by any such other Borrower to any Bank or the
     Administrative Agent under this Agreement or the Notes but for the fact
     that they are unenforceable or not allowable due to the existence of a
     bankruptcy, reorganization or similar proceeding involving such Borrower.
     Notwithstanding the foregoing, the liability of each Domestic Borrower
     under the foregoing guarantee shall at no time exceed the maximum amount of
     liability which could be asserted against such Domestic Borrower hereunder
     without (a) rendering such Domestic Borrower "insolvent" within the meaning
     of Section 101(32) of the Bankruptcy Code, Section 2 of the Uniform
     Fraudulent Transfer Act (the "UFTA") or Section 2 of the Uniform Fraudulent
     Conveyance Act (the "UFCA"), (b) leaving such Domestic Borrower with
     unreasonably small capital or assets, within the meaning of Section 548 of
     the Bankruptcy Code, Section 4 of the UFTA, or Section 5 of the UFCA, or
     (c) leaving such Domestic Borrower unable to pay its debts as they become
     due within the meaning of Section 548 of the Bankruptcy Code, Section 4 of
     the UFTA or Section 6 of the UFCA.

               SECTION 7.02.  Validity.  The obligations of each Domestic 
     Borrower under this Article VII are independent of the obligations of the
     other Borrowers guaranteed hereunder, and a separate action or actions may
     be brought and prosecuted against each Domestic Borrower to enforce its
     obligations under this Article VII, irrespective of whether any action is
     brought against any other Domestic Borrower or whether any other Domestic
     Borrower is joined in any such action or actions. The obligations of each
     Domestic Borrower under this Article VII shall be unconditional
     irrespective of (a) the genuineness, validity, regularity or enforceability
     of the obligations of the other Borrowers under this Agreement, any Note or
     any Assumption Letter, (b) any law, regulation or order of any jurisdiction
     affecting any term of any obligation of any Borrower under this Agreement
     or the rights of any Bank or the Administrative Agent with respect thereto,
     (c) any change in the time, manner or place of payment of, or in any other
     term of, all or any of the obligations of any Borrower guaranteed under
     this Article VII, or any other amendment or waiver of or any consent to
     departure from this Agreement or the Notes, (d) any change, restructuring
     or termination of the corporate structure or existence of any Borrower or
     any of its Subsidiaries, or (e) to the fullest

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     extent permitted by applicable law, any other circumstance which might
     otherwise constitute a legal or equitable discharge of a surety or
     guarantor.

               SECTION 7.03.  Waivers.  Each Domestic Borrower hereby expressly 
     waives promptness, diligence, presentment, protest and any other notice
     with respect to its obligations under this Article VII and any requirement
     that any right or power be exhausted or any action be taken against any
     other Borrower and all notices and demands whatsoever.

               SECTION 7.04.  Subrogation.  Each Domestic Borrower shall be
     subrogated to the rights of the Banks or the Administrative Agent against
     any other Borrower hereunder only after the Banks and the Administrative
     Agent shall have been paid in full all such amounts, with interest thereon,
     for which such other Borrower shall have become indebted hereunder.

               SECTION 7.05.  Acceleration.  Each Domestic Borrower agrees that,
     as between it, on the one hand, and the Banks and the Administrative Agent,
     on the other hand, the obligations of each other Borrower guaranteed by it
     under this Article VII may be declared to be forthwith due and payable, or
     may be deemed automatically to have been accelerated, as provided in
     Section 6.01 hereof for purposes of this Article VII, notwithstanding any
     stay, injunction or other prohibition (whether in a bankruptcy proceeding
     affecting such other Borrower or otherwise) preventing such declaration as
     against such other Borrower and that, in the event of such declaration or
     automatic acceleration, such obligations (whether or not due and payable by
     such other Borrower) shall forthwith become due and payable by such
     Domestic Borrower for purposes of this Article VII.

               SECTION 7.06.  Reinstatement.  Each Domestic Borrower's 
     obligations under this Article VII shall be reinstated if at any time any
     payment received by any Bank or the Administrative Agent from any other
     Borrower hereunder is required to be repaid or returned by such Bank or the
     Administrative Agent, all as though such payment had not been made.

               SECTION 7.07.  Continuing Guaranty; Assignments.  This guarantee
     shall (a) remain in full force and effect until the later of (i) the cash
     payment in full of all of the obligations guaranteed under this Article VII
     and (ii) the Termination Date, (b) be binding upon each Domestic Borrower,
     its successors and assigns and (c) inure to the benefit of, and be
     enforceable by, the Banks and the Administrative Agent and their
     successors, transferees and assigns (provided that the applicable transfers
     and assignments are made in accordance with the terms of this Agreement).

               SECTION 7.08.  Contribution.  (a)  To the extent that any 
     Domestic Borrower shall make a payment under this Article VII (a "Guaranty
     Payment"), then such Domestic Borrower shall be entitled to contribution
     and indemnification from, and be reimbursed by, each of the other Domestic
     Borrowers in an amount, for each such other Domestic Borrower, equal to a
     fraction of such Guaranty Payment, the numerator of which is such Domestic
     Borrower's "Allocable Guaranty Amount" (as defined below) and the
     denominator of which is the sum of the Allocable Guaranty Amounts of all of
     the Domestic Borrowers. Any right to reimbursement arising from a Guaranty
     Payment shall be subordinate in right of payment to the prior payment in
     full, in cash, of all such

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     amounts, with interest thereon, for which the Borrowers shall have become
     indebted hereunder.

               (b)  As of any date of determination, the "Allocable Guaranty
     Amount" of each Domestic Borrower shall be equal to the maximum amount of
     liability which could be asserted against such Domestic Borrower hereunder
     with respect to the applicable Guaranty Payment without (i) rendering such
     Domestic Borrower "insolvent" within the meaning of Section 101(32) of the
     Bankruptcy Code, Section 2 of the UFTA or Section 2 of the UFCA, (ii)
     leaving such Domestic Borrower with unreasonably small capital or assets,
     within the meaning of Section 548 of the Bankruptcy Code, Section 4 of the
     UFTA, or Section 5 of the UFCA, or (iii) leaving such Domestic Borrower
     unable to pay its debts as they become due within the meaning of Section
     548 of the Bankruptcy Code, Section 4 of the UFTA or Section 6 of the
     UFCA.'

          5.   Amendment to Schedule 2.01.  Each Bank's Commitment set forth on
Schedule 2.01 of the Agreement is deleted and replaced by the following amount:

<TABLE> 
     <S>                                       <C>
     The First National Bank of Chicago        $40,000,000
     First Union National Bank
       (formerly known as First Union
       Bank of North Carolina)                 $30,000,000
     Bank of Montreal                          $30,000,000
</TABLE>

          6.   Conditions Precedent.  This Amendment shall become effective and
be deemed effective as of August 18, 1997 (the "Amendment Effective Date"),
except for Section 4 of this Amendment, which shall become and be deemed
effective as of July 3, 1996, subject to the Administrative Agent's receipt of
each of the following, each dated as of the Amendment Effective Date and in
sufficient copies (except in the case of the Notes) for each of the Banks:

          (i)   this Amendment, duly executed by the Company, ICD Marketing
     Services Group Ltd., a company incorporated in England and Wales and
     formerly known as R.R. Donnelley Marketing Services Group Limited ("ICD"),
     each Bank and the Administrative Agent;

          (ii)  A new Committed Note executed by the Company, payable to each
     Bank;

          (iii) A new Committed Note executed by ICD, payable to each Bank;

          (iv)  A certificate of the Secretary of the Company certifying (A)
     copies attached thereto of the resolutions of the Board of Directors of the
     Company authorizing the Company's execution, delivery and performance of
     this Agreement, (B) copies attached thereto of the Certificate of
     Incorporation and by-laws of the Company, and (C) the names and true
     signatures of the officers of the Company authorized to sign this Agreement
     and the Notes and other documents to be executed and delivered by the
     Company hereunder;

          (v)   A certificate of a duly authorized officer of the Company,
     certifying that as of the Amendment Effective Date, (A) the representations
     and warranties contained in Section 4.01 of the Agreement are correct on
     and as of the

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     Amendment Effective Date (other than those which speak expressly as of an
     earlier date), (B) no event shall have occurred and be continuing that
     constitutes an Event of Default or which would constitute an Event of
     Default but for the requirement that notice be given or time elapse or both
     and (C) the conditions for the Amendment Effective Date have been
     satisfied;

          (vi)   A certificate of the Secretary or an Assistant Secretary of 
     ICD, certifying a copy of the resolutions of the Board of Directors of ICD
     approving this Amendment, the names and true signatures of the officers of
     ICD authorized to sign this Amendment and the other documents to be
     executed and delivered by ICD hereunder;

          (vii)  Favorable opinions of Sidley & Austin and the General Counsel 
     of the Company, substantially in the forms delivered by each of them,
     respectively, at the closing of the Agreement, with such changes
     appropriate for this Amendment as are acceptable to the Administrative
     Agent in its reasonable judgment; and

          (viii) Favorable opinions of Sidley & Austin, the General Counsel of 
     the Company and Baker & McKenzie, special United Kingdom counsel to ICD,
     substantially in the forms delivered by each them when ICD became a
     Borrowing Subsidiary, with such changes appropriate for this Amendment as
     are acceptable to the Administrative Agent in its reasonable judgment.

          7.   Covenants, Representations and Warranties.

          (i)    Upon the effectiveness of this Amendment, the Company reaffirms
     all covenants, representations and warranties made by it in the Credit
     Agreement and agrees that all such covenants, representations and
     warranties shall be deemed to have been remade as of the Amendment
     Effective Date.

          (ii)   The Company represents and warrants that no event has occurred
     and is continuing or would result from the execution, delivery or
     performance of this Amendment which constitutes or would constitute an
     Event of Default or which would constitute an Event of Default but for the
     requirement that notice be given or time elapse or both.

          (iii)  Each Borrower represents and warrants that the execution,
     delivery and performance of this Amendment by it (i) are within its
     corporate powers and (ii) have been duly authorized by all necessary
     corporate action on its part.  Each Borrower further represents and
     warrants that this Amendment, as of the date it becomes effective, will
     constitute a valid and binding agreement of such Borrower, enforceable
     against such Borrower in accordance with its terms, subject to the effect
     of any applicable bankruptcy, insolvency, reorganization or other laws
     relating to or affecting the enforcement of creditors' rights generally or
     by equitable principles.

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<PAGE>
 
          8.   Reference to and Effect on Agreement. Upon the effectiveness of
this Amendment, each reference in the Agreement to "this Agreement,"
"hereunder," "hereof," "herein," "hereby" or words of like import shall mean and
be a reference to the Agreement as amended hereby, and each reference to the
Agreement in any instrument, document or agreement executed or delivered in
connection with the Agreement (including without limitation this Amendment)
shall mean and be a reference to the Agreement as amended hereby.

          9.   Reaffirmation.  Each Borrower reaffirms its obligations under the
Agreement (including, without limitation, its obligations under the Guarantee
set forth in Article VII of the Agreement).

          10.  Continuing Effect.  Except as expressly amended hereby, the
Agreement shall continue to be and shall remain in full force and effect in
accordance with its terms.

          11.  Governing Law.  This Amendment shall be governed by, and
construed and interpreted in accordance with, the internal laws (as opposed to
conflict of laws principles) of the State of Illinois.

          12.  Counterparts; Delivery of Facsimiles.  This Amendment may be
executed by the parties hereto in any number of separate counterparts and all of
said counterparts taken together shall be deemed to constitute one and the same
instrument.  Delivery of an executed signature page hereof by facsimile
transmission shall be effective as delivery of a manually-signed counterpart
hereof.

          13.  Return of Original Committed Notes.  Upon the effectiveness of
this Amendment and in exchange for the Committed Notes being delivered pursuant
to this Amendment, each Bank shall mark its original Committed Notes
"superseded" and shall return them to the Company.

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<PAGE>
 
          IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed and delivered by their properly and duly authorized officers as
of the day and year first above written.

                              METROMAIL CORPORATION


                              By:____________________________________
                              Name:
                              Title:


                              THE FIRST NATIONAL BANK OF 
                              CHICAGO, as Administrative Agent and as a 
                              Bank


                              By:____________________________________
                              Name:
                              Title:


                              FIRST UNION NATIONAL BANK (f/k/a 
                              FIRST UNION BANK OF NORTH 
                              CAROLINA)


                              By:____________________________________
                              Name:
                              Title:


                              BANK OF MONTREAL


                              By:____________________________________
                              Name:
                              Title:



Acknowledged and Agreed to:

ICD MARKETING SERVICES GROUP LTD.


By:________________________
Name:
Title:

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