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) February 28, 2013

LEGGETT & PLATT, INCORPORATED

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code 417-358-8131

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 (see General Instruction A.2. below):

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Promotion of Executive Officers

On March 1, 2013, David S. Haffner, Karl G. Glassman and Matthew C. Flanigan entered into new four-year employment agreements and severance benefit agreements with the Company, as described below. In connection with the employment agreements, each of the executive’s positions changed. Subject to the employment and severance benefit agreements, the executive officers generally serve at the pleasure of the Board of Directors.

Mr. Haffner, age 60, whose title was President and CEO, will continue to serve the Company as CEO. Also, the Nominating and Corporate Governance Committee nominated Mr. Haffner to become Board Chair, subject to his re-election to the Board at the Annual Shareholders Meeting on May 9, 2013 and Board approval at its May 2013 meeting. Mr. Haffner was appointed CEO in 2006 and had served as President of the Company since 2002. He served as COO from 1999 to 2006 and as the Company’s Executive Vice President from 1995 to 2002. Mr. Haffner has served the Company in various capacities since 1983.

Mr. Glassman, age 54, was promoted to President and COO. He previously served as Executive Vice President and COO. Mr. Glassman was appointed COO in 2006 and had served as Executive Vice President of the Company since 2002. He served as President of the Residential Furnishings segment from 1999 to 2006, as Senior Vice President of the Company from 1999 to 2002 and as President of Bedding Components from 1996 to 1998. Mr. Glassman has served the Company in various capacities since 1982.

Mr. Flanigan, age 51, was promoted to Executive Vice President and CFO. He previously served the Company as Senior Vice President and CFO. Mr. Flanigan had served the Company as Senior Vice President since 2005 and has served as CFO since 2003. He also served as Vice President from 2003 to 2005, Vice President and President of the Office Furniture Components group from 1999 to 2003 and as Staff Vice President of Operations from 1997 to 1999.

Family Relationships and Related Person Transactions of Haffner and Glassman. Mr. Haffner and Mr. Glassman have no family relationships with any other director or executive officer of the Company. We buy shares of our common stock from our employees from time to time. In 2012 and early 2013, we purchased 110,983 shares from Mr. Haffner for a total of $3,090,852, and 130,035 shares from Mr. Glassman for $3,523,688. All employees, including executive officers, pay a $25 administrative fee for each transaction. If the Company agrees to purchase stock before noon, the purchase price is the closing stock price on the prior business day; if the agreement is made after noon, the purchase price is the closing stock price on the day of purchase.

Pursuant to the employment agreements, Mr. Haffner received 50,000 restricted stock units (RSUs), Mr. Glassman received 45,000 RSUs and Mr. Flanigan received 40,000 RSUs. The terms of the RSUs are described below.

Entry into New Employment Agreements

On March 1, 2013, the Company entered into new employment agreements with David S. Haffner, Karl G. Glassman and Matthew C. Flanigan (the “2013 Employment Agreements”). Each of the 2013 Employment Agreements has a four-year term, expiring on the date of the 2017 Annual Meeting of Shareholders. Except as otherwise noted, benefits provided under the agreements are those generally available to executive officers and/or employees.

Under the 2013 Employment Agreements, the executive may terminate the agreement upon six months prior written notice. The Company may terminate the agreements without cause at any time. In that event, generally, the Company’s obligation to the executive continues for the term of the agreement. The Company may also terminate the agreements for cause, as defined below. The 2013 Employment Agreements subject the executives to non-competition restrictions for a period ending on the later of (i) two years after termination of employment, or (ii) the term of the agreement. During the portion of the non-competition period after termination of employment, the Company will provide health insurance to the executive and his dependents (or the cash equivalent thereof) at least equal to the insurance provided before termination of employment.

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Below are key provisions of the 2013 Employment Agreements.

Reference is made to the 2009 Key Officer Incentive Plan, effective January 1, 2009, filed March 26, 2009 as Appendix B to the Company’s Proxy Statement and the Summary Sheet for Executive Cash Compensation, filed April 2, 2012 as Exhibit 10.3 to the Company’s Form 8-K.

The RSUs were granted pursuant to the Form of Restricted Stock Unit Award attached hereto and incorporated herein by reference as Exhibit 10.1. The RSUs vest 25% on the grant date and, provided that the executive remains an employee, in 25% increments on the first, second and third anniversaries of the grant date. Upon vesting, each RSU is converted into a share of Company common stock. If the Company terminates the executive’s employment without Cause (as defined in the 2013 Employment Agreements), or the executive terminates his employment for Good Reason (as defined in the below-referenced 2013 severance benefit agreements) within one year after a Change in Control (as defined in the Flexible Stock Plan), the RSUs will immediately become 100% vested. The RSUs are not transferrable and the executive has no shareholder rights until the underlying common stock is issued.

The 2013 Employment Agreements may be terminated under the following circumstances.

Termination Following Total Disability

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Executive’s Option to Terminate

The disclosure above is only a brief description of the 2013 Employment Agreements and is qualified in its entirety by the agreements with Mr. Haffner, Mr. Glassman and Mr. Flanigan, each of which is attached as Exhibits 10.2, 10.3 and 10.4, respectively, and incorporated herein by reference.

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Termination of Existing Employment Agreements

The employment agreements with Mr. Haffner, Mr. Glassman and Mr. Flanigan, each dated May 7, 2009 (the “2009 Employment Agreements”) were terminated upon entry of the 2013 Employment Agreements. The 2009 Employment Agreements would have expired, by their respective terms, at the 2013 Annual Meeting of Shareholders which is expected to be held May 9, 2013. Reference is made to the 2009 Employment Agreements which were filed as Exhibits 10.1, 10.2 and 10.3, respectively, to our Form 10-Q on May 8, 2009. A description of the payments that would have been made to the executive upon termination or change in control under the 2009 Employment Agreements can be found in the Company’s proxy statement filed March 30, 2012 under the heading “Potential Payments upon Termination or Change in Control.” The 2013 Employment Agreements described above contain substantially the same provisions as the 2009 Employment Agreements except:

Amendment of Severance Benefit Agreements and Entry into new Severance Benefit Agreement

On March 1, 2013, the Company and Mr. Haffner and Mr. Glassman, respectively, entered into Amended and Restated Severance Benefit Agreements. On the same date, the Company and Mr. Flanigan entered into a new Severance Benefit Agreement in substantially the same form (collectively the “2013 Severance Agreements”). Upon a change in control of the Company, the 2013 Severance Agreements provide for severance payments and benefits during a “Protected Period” following the change in control. The Protected Period is 36 months for Mr. Haffner, 30 months for Mr. Glassman and 24 months for Mr. Flanigan.

In general, a change in control is deemed to occur when: (i) a shareholder acquires shares giving it ownership of 40% or more of our common stock, (ii) the current directors or their successors no longer constitute a majority of the Board of Directors, (iii) after a merger or consolidation with another corporation, less than 65% of the voting securities of the surviving corporation are owned by our former shareholders, or (iv) the Company is liquidated or sells substantially all of its assets to an unrelated third party.

The payments and benefits payable under the 2013 Severance Agreements are subject to a “double trigger”; that is, they become payable only after both (i) a change in control of the Company and (ii) the executive officer’s employment is terminated by the Company (except for cause or upon disability) or the executive officer terminates his employment for “good reason.” In general, the executive officer would have good reason to terminate his employment if he were required to relocate or experienced a reduction in job responsibilities, title, compensation or benefits, or if the successor company did not assume the obligations of the 2013 Severance Agreement. The Company may cure the “good reason” for termination within 30 days of receiving notice from the executive. Events considered grounds for termination by the Company for cause under the 2013 Severance Agreements are substantially the same as those in the 2013 Employment Agreements described above. The 2013 Severance Agreements have no fixed termination period.

Upon termination of employment by the Company (except for cause or upon disability) or by the executive for good reason following a change in control, the Company will provide the following payments and benefits:

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All amounts received by Mr. Haffner, Mr. Glassman or Mr. Flanigan as health insurance or fringe benefits from a new full-time job will reduce the benefits under the 2013 Severance Agreements. However the executive is not required to mitigate the amount of any termination payment or benefit provided under the agreements.

The disclosure above is only a brief description of the 2013 Severance Agreements and is qualified in its entirety by such agreements with Mr. Haffner, Mr. Glassman and Mr. Flanigan, each of which is attached as Exhibits 10.5, 10.6 and 10.7, respectively, and incorporated herein by reference.

Changes from Prior Severance Benefit Agreements

The 2013 Severance Agreements with Mr. Haffner and Mr. Glassman are substantially the same as the prior severance benefit agreements, except as described below. Reference is made to the Amended and Restated Severance Benefit Agreements, dated May 7, 2009, between the Company and Mr. Haffner and Mr. Glassman, which were filed as Exhibits 10.5 and 10.6, respectively, to our Form 10-Q on May 8, 2009 (the “2009 Severance Agreements”). A description of the material terms of the 2009 Severance Agreements can be found in the Company’s proxy statement filed March 30, 2012 under the heading “Potential Payments upon Termination or Change in Control.” The material differences between the 2013 Severance Agreements and the 2009 Severance Agreements are:

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Amendment of Profitable Growth Incentive Program

On February 28, 2013, the Compensation Committee amended the terms and conditions of the Profitable Growth Incentive (PGI) Program and granted growth performance stock units (GPSUs) to certain key management employees including our named executive officers—David S. Haffner, Karl G. Glassman, Matthew C. Flanigan and Joseph D. Downes, Jr., SVP & President – Industrial Materials Segment. The Committee had previously approved the form of award and terms and conditions of the PGI and GPSUs at its December 10, 2012 meeting.

The PGI awards were granted under the Company’s Flexible Stock Plan, amended and restated, effective as of May 10, 2012, which was filed March 30, 2012 as Appendix A to the Company’s Definitive Proxy Statement for the Annual Meeting of Shareholders. The Committee granted the GPSUs in accordance with the Form of Profitable Growth Incentive Award Agreement and Terms and Conditions, which is attached hereto and incorporated herein by reference as Exhibit 10.8.

Each of the above executives were granted a number of GPSUs determined by multiplying the executive’s current base annual salary by an award multiple (approved by the Compensation Committee), and dividing this amount by the average closing price of the Company’s common stock for the ten business days immediately following the date of the Company’s fourth quarter earnings press release. The number of GPSU’s that will ultimately vest will depend upon the Revenue Growth and EBITDA Margin of the Company (for Haffner, Glassman and Flanigan) and of the Industrial Materials Segment (for Downes) at the end of a 2-year performance period beginning January 1, 2013 and ending December 31, 2014. The percentage of vested GPSUs will range from 0% to 250% of the number granted according to a payout schedule.

Below is the payout schedule as adopted by the Compensation Committee in December 2012, which was revised.

FORM OF PAYOUT SCHEDULE ADOPTED DECEMBER 2012

X = Threshold EBITDA Margin target to be set by the Compensation Committee

Y= Threshold Revenue Growth target to be set by the Compensation Committee

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At its February 28 meeting, the Compensation Committee revised the form of payout schedule for the GPSUs and set the performance targets for our named executive officers as shown below.

The calculations of EBITDA Margin and Revenue Growth can be found in the Award Formula for 2013-2014 Profitable Growth Incentive Program attached hereto and incorporated herein by reference as Exhibit 10.9 and the Form of Profitable Growth Incentive Award Agreement and Terms and Conditions. Payouts will be interpolated for achievement falling between the target levels shown above. At its February 28 meeting, the Compensation Committee revised the calculation of Revenue Growth by providing for an adjustment to the percentage of growth achieved by the Company or applicable profit center. The percentage of Revenue Growth achieved will be increased or decreased based on the difference between forecasted GDP growth minus actual GDP growth within the 2-year performance period, but this adjustment will only be made if the difference is greater than plus or minus 1%.

Fifty percent of the vested GPSUs will be paid out in cash and the Company intends to pay out the remaining fifty percent in shares of the Company’s common stock, although the Company reserves the right to pay up to one hundred percent in cash. The awards will be paid by March 15, 2015. Cash will be paid equal to the number of vested GPSUs multiplied by the closing market price of the Company’s common stock on the last business day of the performance period. Shares will be issued on a one-to-one basis for vested GPSUs. The amount of cash paid and number of shares issued will be reduced for applicable tax withholding. GPSUs may not be transferred, assigned, pledged or otherwise encumbered, and have no voting or dividend rights.

The GPSUs will normally vest on the last day of the 2-year performance period. If the executive has a separation from service other than for retirement, death or disability, before the GPSUs vest, they are immediately forfeited. If the separation of service is due to retirement, death or disability, the GPSUs will vest on a pro-rata basis for the number of days in the performance period prior to the executive’s termination. However, in the event of disability, the GPSUs will continue to vest for 18 months after disability begins. Under certain circumstances, if a change in control of the Company occurs and the executive’s employment is terminated, the GPSUs will vest and the executive will receive a 250% payout.

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The above referenced terms and conditions contain a non-competition covenant for two years after payout, where, if violated, the executive must repay the Company any gain from the GPSUs. Also, if within 24 months of payment, the Company is required to restate previously reported financial statements, the executive must repay any amounts paid in excess of the amount that would have been paid based on the restated financial results.

The foregoing is only a summary of the terms and conditions of the PGI and GPSUs and is qualified in its entirety by reference to the Form of Profitable Growth Incentive Award Agreement and Terms and Conditions. All future awards under the PGI Program are expected to be made pursuant to the Form of Profitable Growth Incentive Award Agreement and Terms and Conditions attached as Exhibit 10.8. If the terms and conditions of future grants are materially different, the Company will make a subsequent filing of the updated form at that time.

Grants of GPSUs under the Profitable Growth Incentive Program

On February 28, 2013, the Compensation Committee granted GPSUs to our named executive officers in the amounts as shown below.

Paul R. Hauser, a named executive officer in our Summary Compensation Table of our proxy statement filed March 30, 2012, retired from the Company on February 18, 2012. Therefore, he does not participate in the PGI Program.

Item 9.01 Financial Statements and Exhibits.

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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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EXHIBIT INDEX

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