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): May 28, 2014

The Hillshire Brands Company

(Exact name of registrant as specified in charter)

400 South Jefferson Street, Chicago, Illinois 60607

(Address of principal executive offices)

Registrant’s telephone number, including area code: (312) 614-6000

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):

On May 28, 2014, The Hillshire Brands Company, a Maryland corporation (“Hillshire”), entered into a joinder letter (the “First Commitment Letter Joinder”) to Hillshire’s commitment letter (the “Commitment Letter”) dated as of May 12, 2014, previously filed as Exhibit 10.1 to Hillshire’s Current Report on Form 8-K filed May 12, 2014, which amended the Commitment Letter to, among other things, add JPMorgan Chase Bank, N.A. and J.P. Morgan Securities LLC as additional financial institutions and reallocate the commitments thereunder.

Additionally, on May 28, 2014, Hillshire entered into a second joinder letter (the “Second Commitment Letter Joinder”) to Hillshire’s Commitment Letter which amended the Commitment Letter to, among other things, add Royal Bank of Canada as an additional financial institution and reallocate the commitments thereunder.

The foregoing descriptions of the First Commitment Letter Joinder and the Second Commitment Letter Joinder do not purport to be complete and are subject to, and qualified in their entirety by, the full text of the First Commitment Letter Joinder and the Second Commitment Letter Joinder, which are attached hereto as Exhibits 10.1 and 10.2 respectively and incorporated herein by reference.

(d) Exhibits

10.1 Joinder letter, dated as of May 28, 2014, by and among The Hillshire Brands Company, Goldman Sachs Bank USA, Goldman Sachs Lending Partners LLC, JPMorgan Chase Bank, N.A. and J.P. Morgan Securities LLC.

10.2 Joinder letter, dated as of May 28, 2014, by and among The Hillshire Brands Company, Goldman Sachs Bank USA, Goldman Sachs Lending Partners LLC and Royal Bank of Canada.

Forward-Looking Statements

This Current Report on Form 8-K contains certain forward-looking statements with respect to the financial condition, results of operations and business of Hillshire and the combined businesses of Pinnacle Foods Inc. (“Pinnacle”) and Hillshire and certain plans and objectives of Hillshire with respect thereto, including the expected benefits of the proposed merger. These forward-looking statements can be identified by the fact that they do not relate only to historical or current facts. Forward-looking statements often use words such as “anticipate”, “target”, “expect”, “estimate”, “intend”, “plan”, “goal”, “believe”, “hope”, “aim”, “continue”, “will”, “may”, “would”, “could” or “should” or other words of similar meaning or the negative thereof. There are several factors which could cause actual plans and results to differ materially from those expressed or implied in forward-looking statements. Such factors include, but are not limited to, the expected closing date of the transaction; the possibility that the expected synergies and value creation from the proposed merger will not be realized, or will not be realized within

the expected time period; the risk that the businesses will not be integrated successfully; disruption from the merger making it more difficult to maintain business and operational relationships; the risk that unexpected costs will be incurred; changes in economic conditions, political conditions, trade protection measures, licensing requirements and tax matters; the possibility that the merger does not close, including, but not limited to, due to the failure to satisfy the closing conditions, including the receipt of approval of both Hillshire’s stockholders and Pinnacle’s stockholders; and the risk that financing for the transaction may not be available on favorable terms. These forward-looking statements are based on numerous assumptions and assessments made by Hillshire in light of its experience and perception of historical trends, current conditions, business strategies, operating environment, future developments and other factors it believes appropriate. By their nature, forward-looking statements involve known and unknown risks and uncertainties because they relate to events and depend on circumstances that will occur in the future. The factors described in the context of such forward-looking statements in this announcement could cause Hillshire’s plans with respect to Pinnacle, actual results, performance or achievements, industry results and developments to differ materially from those expressed in or implied by such forward-looking statements. Although it is believed that the expectations reflected in such forward-looking statements are reasonable, no assurance can be given that such expectations will prove to have been correct and persons reading this announcement are therefore cautioned not to place undue reliance on these forward-looking statements which speak only as at the date of this announcement. Hillshire assumes no obligation to update the information contained in this announcement (whether as a result of new information, future events or otherwise), except as required by applicable law. A further list and description of risks and uncertainties can be found in Hillshire’s Annual Report on Form 10-K for the fiscal year ended June 29, 2013 and in its reports on Form 10-Q and Form 8-K.

Additional Information and Where to Find It

The proposed merger transaction involving Hillshire and Pinnacle will be submitted to the respective stockholders of Hillshire and Pinnacle for their consideration. In connection with the proposed merger, Hillshire will prepare a registration statement on Form S-4 that will include a joint proxy statement/prospectus for the stockholders of Hillshire and Pinnacle to be filed with the Securities and Exchange Commission (the “SEC”), and each will mail the joint proxy statement/prospectus to their respective stockholders and file other documents regarding the proposed transaction with the SEC. Hillshire and Pinnacle urge investors and stockholders to read the joint proxy statement/prospectus when it becomes available, as well as other documents filed with the SEC, because they will contain important information. Investors and security holders will be able to receive the registration statement containing the proxy statement/prospectus and other documents free of charge at the SEC’s web site, http://www.sec.gov. These documents can also be obtained (when they are available) free of charge from Hillshire upon written request to the Investor Relations Department, 400 South Jefferson Street, Chicago, Illinois 60607, telephone number (312) 614-8100 or from Hillshire’s website, http://investors.hillshirebrands.com, or from Pinnacle upon written request to the Investor Relations Department, 399 Jefferson Road, Parsippany, New Jersey, 07054, telephone number (973) 434-2924, or from Pinnacle’s website, http://investors.pinnaclefoods.com.

Participants in Solicitation

Hillshire, Pinnacle and their respective directors and executive officers and other members of management and employees may be deemed to be participants in the solicitation of proxies from the respective stockholders of Hillshire and Pinnacle in favor of the merger. Information regarding the persons who may, under the rules of the SEC, be deemed participants in the solicitation of the respective stockholders of Hillshire and Pinnacle in connection with the proposed merger will be set forth in the joint proxy statement/prospectus when it is filed with the SEC. You can find information about Hillshire’s executive officers and directors in its definitive proxy statement for its 2013 Annual Meeting of Stockholders, which was filed with the SEC on September 12, 2013. You can find more information about Pinnacle’s executive officers and directors in its definitive proxy statement for its 2014 Annual Meeting of Stockholders, which was filed with the SEC on April 30, 2014. You can obtain free copies of these documents from Hillshire and Pinnacle using the contact information above.

Non-Solicitation

This communication shall not constitute an offer to sell or the solicitation of an offer to sell or the solicitation of an offer to buy any securities, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended.

SIGNATURES

Pursuant to the requirement 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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