<Page> Exhibit 99.906.cert FORM N-CSR ITEM 11(b) EXHIBIT CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 The undersigned hereby certify in their capacity as Treasurer and President, respectively, of North Carolina Municipals Portfolio (the "Portfolio") that: (a) the Annual Report of the Portfolio on Form N-CSR for the period ended August 31, 2004 (the "Report") fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and (b) the information contained in the Report fairly presents, in all material respects, the financial condition and the results of operations of the Portfolio for such period. A SIGNED ORIGINAL OF THIS WRITTEN STATEMENT REQUIRED BY SECTION 906 HAS BEEN PROVIDED TO THE TRUST AND WILL BE RETAINED BY THE TRUST AND FURNISHED TO THE SECURITIES AND EXCHANGE COMMISSION OR ITS STAFF UPON REQUEST. North Carolina Municipals Portfolio Date: October 21, 2004 /s/ Barbara E. Campbell - ----------------------- Barbara E. Campbell Treasurer Date: October 21, 2004 /s/ Thomas J. Fetter - -------------------- Thomas J. Fetter President