UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

June 18, 2012/June 15, 2012

(Date of Report/Date of earliest event reported)

DOMTAR CORPORATION

(Exact name of registrant as specified in its charter)

395 de Maisonneuve Blvd. West

Montreal, Quebec

Canada H3A 1L6

(Address and zip code of principal executive offices)

(514) 848-5555

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

New Credit Facility

On June 15, 2012, Domtar Corporation (the “Company”) amended and restated its existing Credit Agreement (as so amended and restated, the “Credit Agreement”), among the Company and certain of its subsidiaries as borrowers (collectively, the “Borrowers”) and the lenders and agents party thereto. The Company intends to use the Credit Agreement for general corporate purposes, including working capital, capital expenditures and acquisitions.

The Credit Agreement provides for a revolving credit facility (including a letter of credit subfacility and a swingline subfacility) that matures on June 15, 2017. The maximum aggregate amount of availability under the revolving Credit Agreement is $600 million, which may be borrowed in US Dollars, Canadian Dollars (in an amount up to the Canadian Dollar equivalent of $150 million) and Euros (in an amount up to the Euro equivalent of $200 million). Borrowings may be made by the Company, by its U.S. subsidiary Domtar Paper Company, LLC, by its Canadian subsidiary Domtar Inc. and by any additional borrower designated by the Company in accordance with the Credit Agreement. The Company may increase the maximum aggregate amount of availability under the revolving Credit Agreement by up to $400 million, and the Borrowers may extend the final maturity of the Credit Agreement by one year, if, in each case, certain conditions are satisfied, including (i) the absence of any event of default or default under the Credit Agreement and (ii) the consent of the lenders participating in each such increase or extension, as applicable.

Borrowings under the Credit Agreement will bear interest at a rate dependent on the Company’s credit ratings at the time of such borrowing and will be calculated at the Borrowers’ option according to a base rate, prime rate, LIBO rate, EURIBO rate or the Canadian bankers’ acceptance rate plus an applicable margin, as the case may be. In addition, the Company must pay facility fees quarterly at rates dependent on the Company’s credit ratings.

The Credit Agreement contains customary covenants for transactions of this type, including two financial covenants: (i) an interest coverage ratio, as defined in the Credit Agreement, that must be maintained at a level of not less than 3.0 to 1 and (ii) a leverage ratio, as defined in the Credit Agreement, that must be maintained at a level of not greater than 3.75 to 1.

All borrowings under the Credit Agreement are unsecured. However, certain domestic subsidiaries of the Company will unconditionally guarantee any obligations from time to time arising under the Credit Agreement, and certain subsidiaries of the Company that are not organized in the United States will unconditionally guarantee any obligations of Domtar Inc., the Canadian subsidiary borrower, or of additional borrowers that are not organized in the United States, under the Credit Agreement, in each case, subject to the provisions of the Credit Agreement.

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If there is a change of control, as defined under the Credit Agreement, the Credit Agreement will be terminated and any outstanding obligations under the Credit Agreement will automatically become immediately due and payable. In addition, the Credit Agreement also contains customary events of default. If an event of default under the Credit Agreement occurs and is continuing, then the administrative agent may declare any outstanding obligations under the Credit Agreement to be immediately due and payable. In addition, if the Company or any of its material subsidiaries becomes the subject of voluntary or involuntary proceedings under any bankruptcy, insolvency or similar law, then any outstanding obligations under the Credit Agreement will automatically become immediately due and payable.

The above description of the Credit Agreement is not complete and is qualified in its entirety by reference to the full text of the Credit Agreement, a copy of which will be filed as an exhibit to the Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2012.

The information required by Item 2.03 contained in Item 1.01 above is incorporated by reference into this Item 2.03.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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