TENDER OFFER STATEMENT UNDER SECTION 14(d)(1)
OR SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934

MF MERGER SUB CORP.
(Name of Filing Persons (Offeror)) a wholly owned subsidiary of

MF INVESTOR GP LLC
FORTRESS CREDIT ADVISORS LLC
(Names of Filing Persons (Other Person))

MF Merger Sub Corp.
c/o Fortress Investment Group
1345 Avenue of the Americas
46^th Floor
New York, New York 10105
Attention: Constantine M. Dakolias
Telephone: (212) 798-6100
(Name, address and telephone number of person authorized to receive notices and communications on behalf of filing persons)

David E. Zeltner
Milbank, Tweed, Hadley & McCloy LLP
One Chase Manhattan Plaza
New York, New York 10005
Telephone: (212) 530-5000

*: Estimated for purposes of calculating the filing fee only. The transaction valuation was calculated by adding the sum of (i) 14,433,154 shares of common stock, par value $0.01 per share (the "Shares"), of MicroFinancial Corporation ("MicroFinancial") outstanding multiplied by the offer price of $10.20 per share, (ii) 130,239 Shares subject to outstanding restricted stock units, which reflects the maximum number of restricted stock units that may be outstanding at the time the offer is completed, multiplied by the offer price of $10.20 per share, (iii) 433,028 Shares issuable pursuant to outstanding options multiplied by the offer price of $10.20 per share less the weighted average exercise price for such options of $3.723 per share and (iv) 51,894 Shares (including Shares issuable pursuant to restricted stock units) to be issued to directors and certain members of management of MicroFinancial following December 13, 2014, multiplied by the offer price of $10.20 per share. The calculation of the filing fee is based on information provided by MicroFinancial as of December 12, 2014 (with respect to the number of Shares of common stock, restricted stock units and options) and September 30, 2014 (with respect to the exercise price of such options).
**: The filing fee was calculated in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, and Fee Rate Advisory No. 1 for Fiscal Year 2015, issued August 29, 2014, by multiplying the Transaction Valuation by 0.0001162.

Check the following box if the filing is a final amendment reporting the results of the tender offer: o

This Tender Offer Statement on Schedule TO (this "Schedule TO") relates to the tender offer by MF Merger Sub Corp., a Massachusetts corporation (the "Offeror") and a direct wholly owned subsidiary of MF Parent LP, a Delaware limited partnership ("Parent"). Parent is managed by its general partner, MF Investor GP LLC, a Delaware limited liability company ("MF GP"). MF GP is owned, directly or indirectly, by investment funds (the "Investment Funds") managed within the Credit Funds business of Fortress Investment Group LLC (listed on the NYSE under the symbol "FIG"), a leading global investment management firm ("FIG"). Fortress Credit Advisors LLC, an affiliate of FIG ("Fortress Credit Advisors"), serves as an investment manager for each of the Investment Funds. As described in the Offer to Purchase, certain of the Investment Funds have committed to provide funding for the consideration to be paid in the Offer and the Merger (each as defined herein) and to pay certain fees and expenses in connection therewith. Parent, the Offeror and Fortress Credit Advisors, each as co-bidders hereunder, are offering to purchase for cash for all of the outstanding shares of common stock, par value $0.01 per share (the "Common Stock" or the "Shares"), of MicroFinancial Incorporated (the "Company") at a price of $10.20 per share, net to the seller in cash without interest and less any applicable withholding taxes, upon the terms and conditions set forth in the offer to purchase dated December 19, 2014 (the "Offer to Purchase"), a copy of which is attached as Exhibit (a)(1)(A), and in the related letter of transmittal (the "Letter of Transmittal") which, together with any amendments or supplements, collectively constitute the "Offer."

All the information set forth in the Offer to Purchase, including the information set forth on the cover page and in the INTRODUCTION of the Offer to Purchase and Schedule I thereto, is incorporated by reference herein in response to Items 1 through 9 and Item 11 of this Schedule TO, and is supplemented by the information specifically provided in this Schedule TO.

The information set forth in the Offer to Purchase under the caption "Summary Term Sheet" is incorporated herein by reference.

(a) Name and Address. The name of the subject company, and the address and telephone number of its principal executive offices are as follows:

MicroFinancial Incorporated
16 New England Executive Park, Suite 200
Burlington, MA 01803
(781) 994-4800

(b) Securities. This Schedule TO relates to the Offer by the Offeror to purchase all issued and outstanding Shares. As of December 12, 2014, based on information provided by the Company, there were 14,433,154 Shares issued and outstanding. The information set forth in the Offer to Purchase under the caption "Introduction" is incorporated herein by reference.

(c) Trading Market and Price. The information set forth under the caption "The Tender Offer—Section 6 (Price Range of Shares; Dividends)" of the Offer to Purchase is incorporated herein by reference.

(a)-(c) Name and Address; Business and Background of Entities; and Business and Background of Natural Persons. The information set forth in the Offer to Purchase under the following captions, together with Schedule I attached thereto, is incorporated herein by reference:

The Tender Offer—Section 8 (Certain Information Concerning Fortress Credit Advisors, Parent and the Offeror)

(a) Material Terms. The information set forth in the Offer to Purchase is incorporated herein by reference.

(a) Transactions. The information set forth in the Offer to Purchase under the following captions is incorporated herein by reference: