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                                                                      EX-99.CERT

                          MONEY MARKET VARIABLE ACCOUNT

         CERTIFICATION PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT


   I, Richard M. Hisey, certify that:

   1. I have reviewed this report on Form N-CSR of Money Market Variable
      Account;

   2. Based on my knowledge, this report does not contain any untrue statement
      of a material fact or omit to state a material fact necessary to make the
      statements made, in light of the circumstances under which such statements
      were made, not misleading with respect to the period covered by this
      report;

   3. Based on my knowledge, the financial statements, and other financial
      information included in this report, fairly present in all material
      respects the financial condition, results of operations, changes in net
      assets, and cash flows (if the financial statements are required to
      include a statement of cash flows) of the registrant as of, and for, the
      periods presented in this report;

   4. The registrant's other certifying officers and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Rule 30a-3(c) under the Investment Company Act of 1940) for the
      registrant and have:

        a. designed such disclosure controls and procedures, or caused such
           disclosure controls and procedures to be designed under our
           supervision, to ensure that material information relating to the
           registrant, including its consolidated subsidiaries, is made known to
           us by others within those entities, particularly during the period in
           which this report is being prepared;

        b. evaluated the effectiveness of the registrant's disclosure controls
           and procedures and presented in this report our conclusions about the
           effectiveness of the disclosure controls and procedures as of a date
           within 90 days prior to the filing date of this report based on such
           evaluation; and

        c. disclosed in this report any change in the registrant's internal
           control over financial reporting that occurred during the
           registrant's most recent fiscal half-year (the registrant's second
           fiscal half-year in the case of an annual report) that has materially
           affected, or is reasonably likely to materially affect, the
           registrant's internal control over financial reporting; and

   5. The registrant's other certifying officers and I have disclosed to the
      registrant's auditors and the audit committee of the registrant's board of
      directors (or persons performing the equivalent functions):

        a. all significant deficiencies and material weaknesses in the design or
           operation of internal control over financial reporting which are
           reasonably likely to adversely affect the registrant's ability to
           record, process, summarize, and report financial information; and

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        b. any fraud, whether or not material, that involves management or other
           employees who have a significant role in the registrant's internal
           control over financial reporting.


Date:  August 23, 2004                RICHARD M. HISEY
       ---------------                ------------------------------------------
                                      Richard M. Hisey
                                      Treasurer (Principal Financial Officer and
                                      Accounting Officer)

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                          MONEY MARKET VARIABLE ACCOUNT

         CERTIFICATION PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT


   I, Robert J. Manning, certify that:

   1. I have reviewed this report on Form N-CSR of Money Market Variable
      Account;

   2. Based on my knowledge, this report does not contain any untrue statement
      of a material fact or omit to state a material fact necessary to make the
      statements made, in light of the circumstances under which such statements
      were made, not misleading with respect to the period covered by this
      report;

   3. Based on my knowledge, the financial statements, and other financial
      information included in this report, fairly present in all material
      respects the financial condition, results of operations, changes in net
      assets, and cash flows (if the financial statements are required to
      include a statement of cash flows) of the registrant as of, and for, the
      periods presented in this report;

   4. The registrant's other certifying officers and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Rule 30a-3(c) under the Investment Company Act of 1940) for the
      registrant and have:

        a. designed such disclosure controls and procedures, or caused such
           disclosure controls and procedures to be designed under our
           supervision, to ensure that material information relating to the
           registrant, including its consolidated subsidiaries, is made known to
           us by others within those entities, particularly during the period in
           which this report is being prepared;

        b. evaluated the effectiveness of the registrant's disclosure controls
           and procedures and presented in this report our conclusions about the
           effectiveness of the disclosure controls and procedures as of a date
           within 90 days prior to the filing date of this report based on such
           evaluation; and

        c. disclosed in this report any change in the registrant's internal
           control over financial reporting that occurred during the
           registrant's most recent fiscal half-year (the registrant's second
           fiscal half-year in the case of an annual report) that has materially
           affected, or is reasonably likely to materially affect, the
           registrant's internal control over financial reporting; and

   5. The registrant's other certifying officers and I have disclosed to the
      registrant's auditors and the audit committee of the registrant's board of
      directors (or persons performing the equivalent functions):

        a. all significant deficiencies and material weaknesses in the design or
           operation of internal control over financial reporting which are
           reasonably likely to adversely affect the registrant's ability to
           record, process, summarize, and report financial information; and

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        b. any fraud, whether or not material, that involves management or other
           employees who have a significant role in the registrant's internal
           control over financial reporting.


Date: August 23, 2004                 ROBERT J. MANNING
      ---------------                 ------------------------------------------
                                      Robert J. Manning
                                      President (Principal Executive Officer)