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): September 8, 2014

MedAssets, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: 678-323-2500

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:

On September 8, 2014, MedAssets, Inc. (the “Company”) entered into a First Increase Joinder to Credit Agreement, dated as of September 8, 2014, by and among the Company and the lenders from time to time party thereto, JPMorgan Chase Bank, N.A., as Administrative Agent, Collateral Agent and L/C Issuer, Bank of America, N.A., as Swing Line Lender, Deutsche Bank Securities Inc., as Syndication Agent, and Barclays Bank PLC, Morgan Stanley Senior Funding, Inc., SunTrust Robinson Humphrey, Inc., Raymond James Bank, FSB and Fifth Third Bank, as Co-Documentation Agents (the “First Increase Joinder”) to that certain credit agreement, dated as of December 13, 2012 by and among the Company, each lender from time to time party thereto, JPMorgan Chase Bank, N.A., as Administrative Agent, Collateral Agent and LIC Issuer, Bank of America, N.A., as Swing Line Lender, Deutsche Bank Securities Inc., as Syndication Agent, and Barclays Bank PLC, Morgan Stanley Senior Funding, Inc., SunTrust Robinson Humphrey, Inc., Raymond James Bank, FSB and Fifth Third Bank, as Co-Documentation Agents (as amended, restated, modified or supplemented from time to time prior to the date hereof) (the “Credit Agreement”). The First Increase Joinder increased the revolving committed amount under the Credit Agreement by $100,000,000 to $300,000,000.

The description of the First Increase Joinder does not purport to be complete and is qualified in its entirety by reference to the First Increase Joinder, a copy of which is filed hereto as Exhibit 99.1 and incorporated herein by reference.

(d) Exhibits

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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