Exhibit 32.2

                           MICROFINANCIAL INCORPORATED
                    CERTIFICATION OF CHIEF FINANCIAL OFFICER
                 REGARDING QUARTERLY REPORT ON FORM 10-Q FOR THE
                          QUARTER ENDED MARCH 31, 2005

      James R. Jackson Jr., Vice President and Chief Financial Officer of
MicroFinancial Incorporated (the "Company"), hereby certifies that, to the best
of his knowledge, based upon a review of the Quarterly Report on Form 10-Q for
the Quarter ended March 31, 2005 (the "Covered Report") and, except as corrected
or supplemented in a subsequent covered report:

- -     the Covered Report fully complies with the requirements of Section 13(a)
      or 15(d) of the Securities Exchange Act of 1934; and

- -     the information contained in the Covered Report fairly presents, in all
      material respects, the financial condition and results of operations of
      the Company.

In Witness Whereof, the undersigned has signed this Certification as of this
16th of May, 2005.

                                 /s/ James R. Jackson Jr.
                                 -----------------------------------------------
                                 James R. Jackson Jr.
                                 Vice President and Chief Financial Officer