<Page>

                                                                  Exhibit 99.1.2

   Certification Required Under Section 906 of the Sarbanes-Oxley Act of 2002

I, Joan S. Freilich, the Chief Financial Officer of Consolidated Edison, Inc.
(the "Company") certify that the Company's Quarterly Report on Form 10-Q for
the quarterly period ended June 30, 2002, which this statement accompanies,
(the "Form 10-Q") fully complies with the requirements of Section 13(a) or
15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)) and
that the information contained in the Form 10-Q fairly presents, in all
material respects, the financial condition and results of operations of the
Company.

                                      /s/ Joan S. Freilich
                                      Joan S. Freilich


Dated: August 12, 2002