<Page> Exhibit 99.906Cert MANAGED SECTORS VARIABLE ACCOUNT CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT I, Richard M. Hisey, certify that, to my knowledge: 1. The Form N-CSR (the "Report") of Managed Sectors Variable Account (the "Registrant") fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and 2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Registrant. Date: August 23, 2004 RICHARD M. HISEY --------------- --------------------------------------- Richard M. Hisey Treasurer (Principal Financial Officer and Accounting Officer) A SIGNED ORIGINAL OF THIS WRITTEN STATEMENT REQUIRED BY SECTION 906 HAS BEEN PROVIDED TO THE REGISTRANT AND WILL BE RETAINED BY THE REGISTRANT AND FURNISHED TO THE SECURITIES AND EXCHANGE COMMISSION OR ITS STAFF UPON REQUEST. <Page> MANAGED SECTORS VARIABLE ACCOUNT CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT I, Robert J. Manning, certify that, to my knowledge: 1. The Form N-CSR (the "Report") of Managed Sectors Variable Account (the "Registrant") fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and 2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Registrant. Date: August 23, 2004 ROBERT J. MANNING --------------- --------------------------------------- Robert J. Manning President (Principal Executive Officer) A SIGNED ORIGINAL OF THIS WRITTEN STATEMENT REQUIRED BY SECTION 906 HAS BEEN PROVIDED TO THE REGISTRANT AND WILL BE RETAINED BY THE REGISTRANT AND FURNISHED TO THE SECURITIES AND EXCHANGE COMMISSION OR ITS STAFF UPON REQUEST.