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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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                                    FORM N-PX

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                     ANNUAL REPORT OF PROXY VOTING RECORD OF
                   REGISTERED MANAGEMENT INVESTMENT COMPANIES

                  Investment Company Act file number 811-02794

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                              MFS SERIES TRUST III
               (Exact name of registrant as specified in charter)

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               111 Huntington Avenue, Boston, Massachusetts 02199
               (Address of principal executive offices) (Zip code)

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                                Susan A. Pereira
                    Massachusetts Financial Services Company
                              111 Huntington Avenue
                           Boston, Massachusetts 02199
                    (Name and address of agents for service)

       Registrant's telephone number, including area code: (617) 954-5000

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                       Date of fiscal year end: January 31

             Date of reporting period: July 1, 2014 - June 30, 2015

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ITEM 1. PROXY VOTING RECORD.



******************************* FORM N-Px REPORT *******************************

ICA File Number: 811-02794
Reporting Period: 07/01/2014 - 06/30/2015
MFS Series Trust III









========================== MFS Global High Yield Fund ==========================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



============================= MFS High Income Fund =============================


ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439T206
Meeting Date: APR 24, 2015   Meeting Type: Annual
Record Date:  MAR 09, 2015

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Robin J. Adams           For       For          Management
1.2   Elect Director Keith E. Busse           For       For          Management
1.3   Elect Director Richard F. Dauch         For       For          Management
1.4   Elect Director Robert E. Davis          For       For          Management
1.5   Elect Director Lewis M. Kling           For       For          Management
1.6   Elect Director John W. Risner           For       For          Management
1.7   Elect Director James R. Rulseh          For       For          Management
2     Ratify Deloitte & Touche LLP as         For       For          Management
      Auditors
3     Advisory Vote to Ratify Named           For       For          Management
      Executive Officers' Compensation




======================= MFS High Yield Pooled Portfolio ========================


ACCURIDE CORPORATION

Ticker:       ACW            Security ID:  00439T206
Meeting Date: APR 24, 2015   Meeting Type: Annual
Record Date:  MAR 09, 2015

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1.1   Elect Director Robin J. Adams           For       For          Management
1.2   Elect Director Keith E. Busse           For       For          Management
1.3   Elect Director Richard F. Dauch         For       For          Management
1.4   Elect Director Robert E. Davis          For       For          Management
1.5   Elect Director Lewis M. Kling           For       For          Management
1.6   Elect Director John W. Risner           For       For          Management
1.7   Elect Director James R. Rulseh          For       For          Management
2     Ratify Deloitte & Touche LLP as         For       For          Management
      Auditors
3     Advisory Vote to Ratify Named           For       For          Management
      Executive Officers' Compensation




======================== MFS Municipal High Income Fund ========================


RED RIVER HEALTH FACILITIES DEVELOPMENT CORPORATION

Ticker:                      Security ID:  75687DAK9
Meeting Date: FEB 23, 2015   Meeting Type: Written Consent
Record Date:  JAN 09, 2015

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management
2     Opt Out Proposal                        None      For          Management


--------------------------------------------------------------------------------

RED RIVER HEALTH FACILITIES DEVELOPMENT CORPORATION

Ticker:                      Security ID:  75687DAN3
Meeting Date: FEB 23, 2015   Meeting Type: Written Consent
Record Date:  JAN 09, 2015

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management
2     Opt Out Proposal                        None      For          Management


--------------------------------------------------------------------------------

RED RIVER HEALTH FACILITIES DEVELOPMENT CORPORATION

Ticker:                      Security ID:  75687DAP8
Meeting Date: FEB 23, 2015   Meeting Type: Written Consent
Record Date:  JAN 09, 2015

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management
2     Opt Out Proposal                        None      For          Management


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RED RIVER HEALTH FACILITIES DEVELOPMENT CORPORATION

Ticker:                      Security ID:  75687DAR4
Meeting Date: FEB 23, 2015   Meeting Type: Written Consent
Record Date:  JAN 09, 2015

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept The Plan                      None      For          Management
2     Opt Out Proposal                        None      For          Management

========== END NPX REPORT



                                   SIGNATURES

Pursuant to the requirements of the Investment Company Act of 1940, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.

Registrant: MFS SERIES TRUST III

By (Signature and Title):  ROBIN STELMACH*
                           ------------------------------------------
                           Robin Stelmach, Principal Executive
                           Officer & President

Date:  August 26, 2015

*By (Signature and Title)  /s/ Susan A. Pereira
                           ----------------------------------------------
                           Susan A. Pereira, as attorney-in-fact

*    Executed by Susan A. Pereira on behalf of Robin Stelmach pursuant to a
     Power of Attorney dated October 1, 2014. (1)

(1)  Incorporated by reference to MFS Institutional Trust (File Nos. 33-37615
     and 811-06174) Post-Effective Amendment No. 38 filed with the SEC via EDGAR
     on October 27, 2014.