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

Date of Report (Date of earliest event reported): March 20, 2012

DEMANDWARE, INC.

(Exact Name of Company as Specified in Charter)

Company’s telephone number, including area code: (888) 553-9216

Not applicable

(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 (see General Instruction A.2. below):

Restatement of Certificate of Incorporation

On March 20, 2012, Demandware, Inc. (the “Company”) filed a restated certificate of incorporation (the “Restated Certificate”) with the Secretary of State of the State of Delaware in connection with the closing of the Company’s initial public offering of shares of its common stock (the “IPO”). The Company’s board of directors and stockholders previously approved the Restated Certificate to be filed in connection with, and to be effective upon, the closing of the IPO.

The Restated Certificate amends and restates the Company’s certificate of incorporation in its entirety to, among other things: (i) eliminate all references to the previously existing series of preferred stock; (ii) authorize 10,000,000 shares of undesignated preferred stock that may be issued from time to time by the Company’s board of directors in one or more series; (iii) eliminate the ability of the Company’s stockholders to take action by written consent in lieu of a meeting; (iv) provide that directors may be removed from office only for cause and only upon the affirmative vote of the holders of at least 66 ²/3% of the votes that all of the Company’s stockholders would be entitled to cast in an annual election of directors; (v) amend the provisions relating to the indemnification of, and limitation on liability of, officers and directors of the Company; and (vi) establish a classified board of directors, divided into three classes, each of whose members will serve for staggered three-year terms.

The foregoing description of the Restated Certificate is qualified by reference to the Restated Certificate, a copy of which is attached hereto as Exhibit 3.1 and is incorporated herein by reference.

Amended and Restated By-Laws

On March 20, 2012, in connection with the closing of the IPO, amended and restated by-laws of the Company (the “Amended and Restated By-Laws”), previously approved by the Company’s board of directors and stockholders, became effective. The Amended and Restated By-Laws amend and restate the Company’s by-laws in their entirety to, among other things: (i) eliminate the ability of the Company’s stockholders to take action by written consent in lieu of a meeting and call special meetings of stockholders; (ii) establish procedures relating to the presentation of stockholder proposals at stockholder meetings; (iii) establish procedures relating to the nomination of directors; and (iv) conform to the provisions of the Restated Certificate.

The foregoing description of the Amended and Restated By-Laws is qualified by reference to the Amended and Restated By-Laws, a copy of which is attached hereto as Exhibit 3.2 and is incorporated herein by reference.

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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