0001104659-12-078776.txt : 20121119 0001104659-12-078776.hdr.sgml : 20121119 20121119092202 ACCESSION NUMBER: 0001104659-12-078776 CONFORMED SUBMISSION TYPE: 485BPOS PUBLIC DOCUMENT COUNT: 8 FILED AS OF DATE: 20121119 DATE AS OF CHANGE: 20121119 EFFECTIVENESS DATE: 20121119 FILER: COMPANY DATA: COMPANY CONFORMED NAME: MFS Series Trust XII CENTRAL INDEX KEY: 0001330967 IRS NUMBER: 000000000 STATE OF INCORPORATION: MA FISCAL YEAR END: 0430 FILING VALUES: FORM TYPE: 485BPOS SEC ACT: 1933 Act SEC FILE NUMBER: 333-126328 FILM NUMBER: 121213297 BUSINESS ADDRESS: STREET 1: 500 BOYLSTON STREET CITY: BOSTON STATE: MA ZIP: 02116 BUSINESS PHONE: 617-954-5000 MAIL ADDRESS: STREET 1: 500 BOYLSTON STREET CITY: BOSTON STATE: MA ZIP: 02116 FILER: COMPANY DATA: COMPANY CONFORMED NAME: MFS Series Trust XII CENTRAL INDEX KEY: 0001330967 IRS NUMBER: 000000000 STATE OF INCORPORATION: MA FISCAL YEAR END: 0430 FILING VALUES: FORM TYPE: 485BPOS SEC ACT: 1940 Act SEC FILE NUMBER: 811-21780 FILM NUMBER: 121213298 BUSINESS ADDRESS: STREET 1: 500 BOYLSTON STREET CITY: BOSTON STATE: MA ZIP: 02116 BUSINESS PHONE: 617-954-5000 MAIL ADDRESS: STREET 1: 500 BOYLSTON STREET CITY: BOSTON STATE: MA ZIP: 02116 0001330967 S000038772 MFS Lifetime 2015 Fund C000119415 A LFTDX C000119416 B LFTBX C000119417 C LFTCX C000119418 I LFTIX C000119419 R1 LFTRX C000119420 R2 LFTSX C000119421 R3 LFTTX C000119422 R4 LFTUX 0001330967 S000038773 MFS Lifetime 2025 Fund C000119423 B LTTBX C000119424 C LTTCX C000119425 I LTTIX C000119426 R1 LTTRX C000119427 R2 LTTSX C000119428 R3 LTTTX C000119429 R4 LTTUX C000119430 A LTTAX 0001330967 S000038774 MFS Lifetime 2035 Fund C000119431 A LFEAX C000119432 B LFEBX C000119433 C LFECX C000119434 I LFEDX C000119435 R1 LFERX C000119436 R2 LFESX C000119437 R3 LFETX C000119438 R4 LFEUX 0001330967 S000038775 MFS Lifetime 2045 Fund C000119439 A LTMAX C000119440 B LTMBX C000119441 C LTMDX C000119442 I LTMKX C000119443 R1 LTMRX C000119444 R2 LTMSX C000119445 R3 LTMTX C000119446 R4 LTMUX 0001330967 S000038776 MFS Lifetime 2055 Fund C000119447 A LFIAX C000119448 B LFIBX C000119449 C LFICX C000119450 I LFIIX C000119451 R1 LFIRX C000119452 R2 LFISX C000119453 R3 LFITX C000119454 R4 LFIUX 485BPOS 1 a12-22896_9485bpos.htm POST-EFFECTIVE AMENDMENT FILED PURSUANT TO SECURITIES ACT RULE 485(B)

 

As filed with the Securities and Exchange Commission on November 19, 2012

 

 

1933 Act File No.   333-126328

 

 

1940 Act File No.    811-21780

 

 

 

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C.  20549

 


 

FORM N-1A

 

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

 

POST-EFFECTIVE AMENDMENT NO. 31

 

AND REGISTRATION STATEMENT

UNDER

THE INVESTMENT COMPANY ACT OF 1940

 

AMENDMENT NO. 32

 

MFSÒ SERIES TRUST XII

(Exact name of Registrant as Specified in Charter)

 

500 Boylston Street, Boston, Massachusetts 02116

(Address of Principal Executive Offices)

 

Registrant’s Telephone Number, including Area Code:  (617) 954-5000

 

Susan S. Newton, Massachusetts Financial Services Company

500 Boylston Street, Boston, Massachusetts 02116

(Name and Address of Agent for Service)

 

APPROXIMATE DATE OF PROPOSED PUBLIC OFFERING:

It is proposed that this filing will become effective (check appropriate box)

 

x immediately upon filing pursuant to paragraph (b)

¨ on [date] pursuant to paragraph (b)

¨ 60 days after filing pursuant to paragraph (a)(i)

¨ on [date] pursuant to paragraph (a)(i)

¨ 75 days after filing pursuant to paragraph (a)(ii)

¨ on [date] pursuant to paragraph (a)(ii) of rule 485.

 

If appropriate, check the following box:

¨ this post-effective amendment designates a new effective date for a previously filed post-effective amendment

 

 

 



 

SIGNATURES

 

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all of the requirements for effectiveness of this Registration Statement pursuant to Rule 485(b) under the Securities Act of 1933 and has duly caused this Post-Effective Amendment to the Registration Statement to be signed on its behalf by the undersigned, thereto duly authorized, in the City of Boston and The Commonwealth of Massachusetts on the 19th day of November 2012.

 

 

MFSÒ SERIES TRUST XII

 

 

 

 

 

By:

JOHN M. CORCORAN*

 

Name:

John M. Corcoran

 

Title:

President

 

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment to its Registration Statement has been signed below by the following persons in the capacities indicated on November 19, 2012.

 

SIGNATURE

 

TITLE

 

 

 

JOHN M. CORCORAN*

 

President (Principal Executive Officer)

John M. Corcoran

 

 

 

 

 

 

 

 

DAVID L. DILORENZO*

 

Principal Financial and Accounting Officer

David L. DiLorenzo

 

 

 

 

 

 

 

 

ROBERT E. BUTLER*

 

Trustee

Robert E. Butler

 

 

 

 

 

 

 

 

MAUREEN R. GOLDFARB*

 

Trustee

Maureen R. Goldfarb

 

 

 

 

 

 

 

 

DAVID H. GUNNING*

 

Trustee

David H. Gunning

 

 

 

 

 

 

 

 

WILLIAM R. GUTOW*

 

Trustee

William R. Gutow

 

 

 

 

 

 

 

 

MICHAEL HEGARTY*

 

Trustee

Michael Hegarty

 

 

 



 

JOHN P. KAVANAUGH*

 

Trustee

John P. Kavanaugh

 

 

 

 

 

 

 

 

ROBERT J. MANNING*

 

Trustee

Robert J. Manning

 

 

 

 

 

 

 

 

J. DALE SHERRATT*

 

Trustee

J. Dale Sherratt

 

 

 

 

 

 

 

 

LAURIE J. THOMSEN*

 

Trustee

Laurie J. Thomsen

 

 

 

 

 

 

 

 

ROBERT W. UEK*

 

Trustee

Robert W. Uek

 

 

 

 

 

*By:

SUSAN S. NEWTON

 

Name:

Susan S. Newton

 

 

as Attorney-in-fact

 

 

 

 

Executed by Susan S. Newton on behalf of those indicated pursuant to a Power of Attorney, dated September 11, 2012 (Trustees), and a Power of Attorney dated September 11, 2012(Corcoran) (DiLorenzo); filed herewith.

 



 

MFS Series Trust I

MFS Series Trust II

MFS Series Trust III

MFS Series Trust IV

MFS Series Trust V

MFS Series Trust VI

MFS Series Trust VII

MFS Series Trust VIII

MFS Series Trust IX

MFS Series Trust X

MFS Series Trust XI

MFS Series Trust XII

MFS Series Trust XIII

MFS Series Trust XIV

MFS Series Trust XV

MFS Series Trust XVI

Massachusetts Investors Growth Stock Fund

Massachusetts Investors Trust

MFS Institutional Trust

MFS Municipal Series Trust

MFS Variable Insurance Trust

MFS Variable Insurance Trust II

MFS California Municipal Fund

MFS Charter Income Trust

MFS Government Markets Income Trust

MFS High Income Municipal Trust

MFS High Yield Municipal Trust

MFS InterMarket Income Trust I

MFS Intermediate High Income Fund

MFS Intermediate Income Trust

MFS Investment Grade Municipal Trust

MFS Multimarket Income Trust

MFS Municipal Income Trust

MFS Special Value Trust

 

(each a “Registrant”)

 

POWER OF ATTORNEY

 

The undersigned, a Trustee of each of the above-mentioned Registrants, hereby severally constitutes and appoints Mark N. Polebaum, Susan S. Newton, Christopher R. Bohane, Thomas H. Connors, Brian E. Langenfeld and Susan A. Pereira, and each of them singly, as true and lawful attorneys, with full power to them and each of them to sign for each of the undersigned, in the names of, and in the capacities indicated below, any

 



 

Registration Statement and any and all amendments thereto and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission for the purpose of registering the Registrant as a management investment company under the Investment Company Act of 1940 and/or the shares issued by the Registrant under the Securities Act of 1933 granting unto my said attorneys, and each of them, acting alone, full power and authority to do and perform each and every act and thing requisite or necessary or desirable to be done in the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys or any of them may lawfully do or cause to be done by virtue thereof.

 

IN WITNESS WHEREOF, the undersigned have hereunto set their hand on this 11th day of September, 2012.

 

 

ROBERT E. BUTLER

 

Trustee

Robert E. Butler

 

 

 

 

 

 

 

 

MAUREEN R. GOLDFARB

 

Trustee

Maureen R. Goldfarb

 

 

 

 

 

 

 

 

DAVID H. GUNNING

 

Trustee

David H. Gunning

 

 

 

 

 

 

 

 

WILLIAM R. GUTOW

 

Trustee

William R. Gutow

 

 

 

 

 

 

 

 

MICHAEL HEGARTY

 

Trustee

Michael Hegarty

 

 

 

 

 

 

 

 

JOHN P. KAVANAUGH

 

Trustee

John P. Kavanaugh

 

 

 

 

 

 

 

 

ROBERT J. MANNING

 

Trustee

Robert J. Manning

 

 

 

 

 

 

 

 

J. DALE SHERRATT

 

Trustee

J. Dale Sherratt

 

 

 



 

LAURIE J. THOMSEN

 

Trustee

Laurie J. Thomsen

 

 

 

 

 

 

 

 

ROBERT W. UEK

 

Trustee

Robert W. Uek

 

 

 



 

MFS Series Trust I

MFS Series Trust II

MFS Series Trust III

MFS Series Trust IV

MFS Series Trust V

MFS Series Trust VI

MFS Series Trust VII

MFS Series Trust VIII

MFS Series Trust IX

MFS Series Trust X

MFS Series Trust XI

MFS Series Trust XII

MFS Series Trust XIII

MFS Series Trust XIV

MFS Series Trust XV

MFS Series Trust XVI

Massachusetts Investors Growth Stock Fund

Massachusetts Investors Trust

MFS Institutional Trust

MFS Municipal Series Trust

MFS Variable Insurance Trust

MFS Variable Insurance Trust II

MFS California Municipal Fund

MFS Charter Income Trust

MFS Government Markets Income Trust

MFS High Income Municipal Trust

MFS High Yield Municipal Trust

MFS InterMarket Income Trust I

MFS Intermediate High Income Fund

MFS Intermediate Income Trust

MFS Investment Grade Municipal Trust

MFS Multimarket Income Trust

MFS Municipal Income Trust

MFS Special Value Trust

 

(each a “Registrant”)

 

POWER OF ATTORNEY

 

The undersigned, being the President and Principal Executive Officer, and Treasurer and Principal Financial and Accounting Officer, respectively, of each of the above-mentioned Registrants, hereby severally constitutes and appoints Mark N. Polebaum, Susan S. Newton, Christopher R. Bohane, Thomas H. Connors, Brian E. Langenfeld and Susan A. Pereira, and each of them singly, as true and lawful attorneys, with full power to them and each of them to sign for each of the undersigned, in the names of, and in the capacities indicated below, any Registration Statement and any and all amendments thereto and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and

 



 

Exchange Commission for the purpose of registering the Registrant as a management investment company under the Investment Company Act of 1940 and/or the shares issued by the Registrant under the Securities Act of 1933 granting unto my said attorneys, and each of them, acting alone, full power and authority to do and perform each and every act and thing requisite or necessary or desirable to be done in the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys or any of them may lawfully do or cause to be done by virtue thereof.

 

IN WITNESS WHEREOF, the undersigned have hereunto set their hand on this 11th day of September, 2012.

 

 

JOHN M. CORCORAN

 

President (Principal Executive Officer)

John M. Corcoran

 

 

 

 

 

 

 

 

DAVID L. DILORENZO

 

Principal Financial and Accounting Officer

David L. DiLorenzo

 

 

 



 

MFSÒ SERIES TRUST XII

 

MFS® LIFETIME® 2015 FUND

MFS® LIFETIME® 2025 FUND

MFS® LIFETIME® 2035 FUND

MFS® LIFETIME® 2045 FUND

MFS® LIFETIME® 2055 FUND

 

INDEX TO EXHIBITS

 

EXHIBIT NO.

 

DESCRIPTION OF EXHIBIT

 

PAGE NO.

 

 

 

 

 

101

 

Risk/Return summary of each fund’s prospectus as an Interactive Data File using eXtensible Business Reporting Language (“XBRL”)

 

 

 


EX-101.INS 2 ck0001330967-20121026.xml XBRL INSTANCE DOCUMENT 485BPOS 2012-10-26 0001330967 2012-10-29 MFS Series Trust XII false 2012-10-26 2012-11-01 <tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's<br />performance.</tt> <div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000038776Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <tt>The fund's investment objective is to seek a high level of total return<br />consistent with its asset allocation until the approximate retirement <br />year in the fund's name; thereafter, the fund will seek total return <br />through a combination of current income and capital appreciation. The <br />asset allocation of the fund will change over time.</tt> <tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt> <tt>The fund is designed to provide diversification among different asset classes<br />for investors with the approximate retirement date in the fund's name. The fund<br />invests substantially all of its assets in other MFS mutual funds, referred to<br />as underlying funds. The underlying funds are selected following a two-stage<br />asset allocation process. The first stage is a strategic asset allocation to<br />establish the percentage of the fund's assets to be invested in the general<br />asset classes of Bond Funds, International Stock Funds, and U.S. Stock Funds, as<br />well as an allocation to underlying funds that have less traditional investment<br />strategies that MFS (Massachusetts Financial Services Company, the fund's<br />investment adviser) believes provide diversification benefits when added to a<br />portfolio consisting of stock and bond funds (referred to as Specialty Funds).<br />The second stage involves the actual selection of underlying funds to represent<br />the asset classes based on underlying fund classifications, historical risk,<br />performance, and other factors. Within the stock fund allocations, MFS seeks to<br />diversify globally (by including domestic and international underlying funds),<br />in terms of market capitalization (by including large, mid, and small<br />capitalization underlying funds) and by style (by including both growth and<br />value underlying funds). Within the bond fund allocation, MFS includes<br />underlying funds with varying degrees of interest rate and credit exposure.<br /><br />As of November 1, 2012, the fund's target allocation among asset classes and the<br />underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;28%<br />MFS Emerging Markets Equity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;57%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12%<br /><br />*&#xA0;&#xA0;The target asset class and underlying fund allocations presented in the table<br />are rounded.<br /><br />The asset class allocations, as well as the underlying funds and their target<br />weightings, are based on an allocation strategy designed for investors with the<br />approximate retirement year in the fund's name. Investors should also consider<br />their age, personal circumstances, risk tolerance, and overall investment<br />strategy and allocation. The asset allocation strategy will become increasingly<br />conservative over time.<br /><br />Upon reaching its stated target year, the fund's allocation strategy will be<br />aligned with the allocation strategy of the MFS Lifetime Retirement Income<br />Fund.&#xA0;&#xA0;It is expected that the fund will be combined with the MFS Lifetime<br />Retirement Income Fund within five years of the date that its asset allocation<br />strategy matches the asset allocation strategy of the MFS Lifetime Retirement<br />Income Fund.&#xA0;&#xA0;The chart below illustrates how the asset allocation strategy of<br />the fund will change over time.<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;ASSET CLASS WEIGHTS FOR TARGET DATE FUNDS<br /><br />71% Bond Funds<br />4%&#xA0;&#xA0;Specialty Funds<br />5%&#xA0;&#xA0;International Stock Funds<br />20% U.S. Stock Funds<br /><br /><br />U.S. Stock Funds &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date&#xA0;&#xA0;<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10<br />Asset class weight%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;54.5%&#xA0;&#xA0;52%&#xA0;&#xA0;&#xA0;&#xA0;41%&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20% &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;20%<br /><br /><br />International Stock Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;24%&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;13%&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;5%<br /><br /><br />Specialty Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;9%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;<br /><br /><br />Bond Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12.5%&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;40%&#xA0;&#xA0;&#xA0;&#xA0;60%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;71%</tt> Summary of Key Information You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds. Example The annual fund operating expenses are based on estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period. The bar chart and performance table are not included because the fund has not had a full calendar year of operations. Investment Objective As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund, including near or after the target date. Principal Risks Shareholder Fees (fees paid directly from your investment): 2013-10-31 Although your actual costs will likely be higher or lower, under these assumptions your costs would be: Performance Information 50000 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): Portfolio Turnover <tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund, including near or after the target<br />date.&#xA0;&#xA0;There is no guarantee that the fund will provide income at or through <br />retirement. An investment in the fund is not a bank deposit and is not insured <br />or guaranteed by the Federal Deposit Insurance Corporation or any other <br />governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /><br />Underlying Funds Risk:&#xA0;&#xA0;MFS' strategy of investing in underlying funds exposes<br />the fund to the risks of the underlying funds. Each underlying fund pursues its<br />own investment objective and strategy and may not achieve its objective.<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor perceptions <br />of these conditions. The price of an equity security can decrease significantly in <br />response to these conditions, and these conditions can affect a single issuer or <br />type of security, issuers within a broad market sector, industry or geographic <br />region, or the market in general.<br /><br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets, greater custody<br />and operational risk, and less developed legal, regulatory, and accounting<br />systems, and greater political, social, and economic instability than developed<br />markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /><br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /><br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /><br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about <br />the issuer, or the market or economy in general, than higher quality debt <br />instruments.<br /><br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. If <br />inflation is negative, principal and income can both decline.<br /><br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /><br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk: The risks of investing in real<br />estate-related securities include certain risks associated with the direct<br />ownership of real estate and the real estate industry in general. These include<br />risks related to general, regional and local economic conditions; fluctuations<br />in interest rates; property tax rates, zoning laws, environmental regulations<br />and other governmental action; cash flow dependency; increased operating<br />expenses; lack of availability of mortgage funds; losses due to natural<br />disasters; overbuilding; losses due to casualty or condemnation; changes in<br />property values and rental rates; and other factors.&#xA0;&#xA0;The securities of smaller<br />real estate-related issuers can be more volatile and less liquid than securities<br />of larger issuers and their issuers can have more limited financial resources.<br /><br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /><br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt> Fees and Expenses Principal Investment Strategies <tt>The bar chart and performance table are not included because the fund has not<br />had a full calendar year of operations.</tt> <tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. The annual fund operating expenses are based on<br />estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current<br />fiscal year expressed as a percentage of the fund's estimated average net assets<br />during the period.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-13 of<br />the fund's statement of additional information Part I.</tt> <div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000038776Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. <div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000038776Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000038776Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> LFIUX 0.0000 87 1007 -0.0354 <tt>R4</tt> 0.0354 0.0000 0.0000 0.0085 0.0439 <tt>Class R4 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LFITX 0.0000 112 1080 -0.0354 <tt>R3</tt> 0.0354 0.0000 0.0025 0.0110 0.0464 <tt>Class R3 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LFISX 0.0000 137 1152 -0.0354 <tt>R2</tt> 0.0354 0.0000 0.0050 0.0135 0.0489 <tt>Class R2 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LFIRX 0.0000 188 1296 -0.0354 <tt>R1</tt> 0.0354 0.0000 0.0100 0.0185 0.0539 <tt>Class R1 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LFIIX 0.0000 87 1007 -0.0354 <tt>I</tt> 0.0354 0.0000 0.0000 0.0085 0.0439 <tt>Class I Shares</tt> 0.0085 <tt>I</tt> 0.0000 LFICX 0.0000 288 188 1296 -0.0354 <tt>C</tt> 0.0354 0.0000 1296 <tt>Class C Shares assuming no redemption at end of period</tt> 0.0100 0.0185 0.0539 <tt>Class C Shares assuming redemption at end of period</tt> 0.0085 <tt>C</tt> 0.0100 LFIBX 0.0000 588 188 1596 -0.0354 <tt>B</tt> 0.0354 0.0000 1296 <tt>Class B Shares assuming no redemption at end of period</tt> 0.0100 0.0185 0.0539 <tt>Class B Shares assuming redemption at end of period</tt> 0.0085 <tt>B</tt> 0.0400 LFIAX 0.0575 681 1593 -0.0354 <tt>A</tt> 0.0354 0.0000 0.0025 0.0110 0.0464 <tt>Class A Shares</tt> 0.0085 <tt>A</tt> 0.0100 <tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate <br />may indicate higher transaction costs and may result in higher taxes when <br />shares are held in a taxable account. These transaction costs, which are not <br />reflected in "Annual Fund Operating Expenses" or in the "Example," affect the <br />fund's performance.</tt> <div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000038775Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <tt>The fund's investment objective is to seek a high level of total return<br />consistent with its asset allocation until the approximate retirement <br />year in the fund's name; thereafter, the fund will seek total return <br />through a combination of current income and capital appreciation. The <br />asset allocation of the fund will change over time.</tt> <tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt> <tt>The fund is designed to provide diversification among different asset classes<br />for investors with the approximate retirement date in the fund's name. The fund<br />invests substantially all of its assets in other MFS mutual funds, referred to<br />as underlying funds. The underlying funds are selected following a two-stage<br />asset allocation process. The first stage is a strategic asset allocation to<br />establish the percentage of the fund's assets to be invested in the general<br />asset classes of Bond Funds, International Stock Funds, and U.S. Stock Funds, as<br />well as an allocation to underlying funds that have less traditional investment<br />strategies that MFS (Massachusetts Financial Services Company, the fund's<br />investment adviser) believes provide diversification benefits when added to a<br />portfolio consisting of stock and bond funds (referred to as Specialty Funds).<br />The second stage involves the actual selection of underlying funds to represent<br />the asset classes based on underlying fund classifications, historical risk,<br />performance, and other factors. Within the stock fund allocations, MFS seeks to<br />diversify globally (by including domestic and international underlying funds),<br />in terms of market capitalization (by including large, mid, and small<br />capitalization underlying funds) and by style (by including both growth and<br />value underlying funds). Within the bond fund allocation, MFS includes<br />underlying funds with varying degrees of interest rate and credit exposure.<br /><br />As of November 1, 2012, the fund's target allocation among asset classes and the<br />underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;28%<br />MFS Emerging Markets Equity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;57%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12%<br /> <br />*&#xA0;&#xA0;The target asset class and underlying fund allocations presented in the table<br />are rounded.<br /><br />The asset class allocations, as well as the underlying funds and their target<br />weightings, are based on an allocation strategy designed for investors with the<br />approximate retirement year in the fund's name. Investors should also consider<br />their age, personal circumstances, risk tolerance, and overall investment<br />strategy and allocation. The asset allocation strategy will become increasingly<br />conservative over time.<br /><br />Upon reaching its stated target year, the fund's allocation strategy will be<br />aligned with the allocation strategy of the MFS Lifetime Retirement Income<br />Fund.&#xA0;&#xA0;It is expected that the fund will be combined with the MFS Lifetime<br />Retirement Income Fund within five years of the date that its asset allocation<br />strategy matches the asset allocation strategy of the MFS Lifetime Retirement<br />Income Fund.&#xA0;&#xA0;The chart below illustrates how the asset allocation strategy of<br />the fund will change over time.<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;ASSET CLASS WEIGHTS FOR TARGET DATE FUNDS<br /><br />71% Bond Funds<br />4%&#xA0;&#xA0;Specialty Funds<br />5%&#xA0;&#xA0;International Stock Funds<br />20% U.S. Stock Funds<br /><br /><br />U.S. Stock Funds &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date&#xA0;&#xA0;<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10<br />Asset class weight%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;54.5%&#xA0;&#xA0;52%&#xA0;&#xA0;&#xA0;&#xA0;41%&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20% &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;20%<br /><br /><br />International Stock Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;24%&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;13%&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;5%<br /><br /><br />Specialty Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;9%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;<br /><br /><br />Bond Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12.5%&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;40%&#xA0;&#xA0;&#xA0;&#xA0;60%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;71%</tt> Summary of Key Information You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds. Example The annual fund operating expenses are based on estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period. The bar chart and performance table are not included because the fund has not had a full calendar year of operations. Investment Objective As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund, including near or after the target date. Principal Risks Shareholder Fees (fees paid directly from your investment): 2013-10-31 Although your actual costs will likely be higher or lower, under these assumptions your costs would be: Performance Information 50000 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): Portfolio Turnover <tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund, including near or after the target<br />date.&#xA0;&#xA0;There is no guarantee that the fund will provide income at or through <br />retirement. An investment in the fund is not a bank deposit and is not insured or <br />guaranteed by the Federal Deposit Insurance Corporation or any other governmental <br />agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /><br />Underlying Funds Risk:&#xA0;&#xA0;MFS' strategy of investing in underlying funds exposes<br />the fund to the risks of the underlying funds. Each underlying fund pursues its<br />own investment objective and strategy and may not achieve its objective.<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline significantly <br />in response to issuer, market, economic, industry, political, regulatory, <br />geopolitical, and other conditions, as well as to investor perceptions of these <br />conditions. The price of an equity security can decrease significantly in response <br />to these conditions, and these conditions can affect a single issuer or type of <br />security, issuers within a broad market sector, industry or geographic region, <br />or the market in general.<br /><br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets, greater custody<br />and operational risk, and less developed legal, regulatory, and accounting<br />systems, and greater political, social, and economic instability than developed<br />markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /><br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /><br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /><br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about <br />the issuer, or the market or economy in general, than higher quality debt <br />instruments.<br /><br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. If <br />inflation is negative, principal and income can both decline.<br /><br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /><br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk: The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real <br />estate and the real estate industry in general. These include risks related to <br />general, regional and local economic conditions; fluctuations in interest rates; <br />property tax rates, zoning laws, environmental regulations and other governmental <br />action; cash flow dependency; increased operating expenses; lack of availability <br />of mortgage funds; losses due to natural disasters; overbuilding; losses due to <br />casualty or condemnation; changes in property values and rental rates; and other <br />factors.&#xA0;&#xA0;The securities of smaller real estate-related issuers can be more volatile <br />and less liquid than securities of larger issuers and their issuers can have more <br />limited financial resources.<br /><br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /><br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt> Fees and Expenses Principal Investment Strategies <tt>The bar chart and performance table are not included because the fund has not<br />had a full calendar year of operations.</tt> <tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. The annual fund operating expenses are based on<br />estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current<br />fiscal year expressed as a percentage of the fund's estimated average net assets<br />during the period.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-13 of<br />the fund's statement of additional information Part I.</tt> <div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000038775Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. <div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000038775Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000038775Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> LTMUX 0.0000 87 786 -0.0245 <tt>R4</tt> 0.0245 0.0000 0.0000 0.0085 0.0330 <tt>Class R4 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LTMTX 0.0000 112 861 -0.0245 <tt>R3</tt> 0.0245 0.0000 0.0025 0.0110 0.0355 <tt>Class R3 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LTMSX 0.0000 137 935 -0.0245 <tt>R2</tt> 0.0245 0.0000 0.0050 0.0135 0.0380 <tt>Class R2 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LTMRX 0.0000 188 1081 -0.0245 <tt>R1</tt> 0.0245 0.0000 0.0100 0.0185 0.0430 <tt>Class R1 Shares</tt> 0.0085 <tt>ALL R</tt> 0.0000 LTMKX 0.0000 87 786 -0.0245 <tt>I</tt> 0.0245 0.0000 0.0000 0.0085 0.0330 <tt>Class I Shares</tt> 0.0085 <tt>I</tt> 0.0000 LTMDX 0.0000 288 188 1081 -0.0245 <tt>C</tt> 0.0245 0.0000 1081 <tt>Class C Shares assuming no redemption at end of period</tt> 0.0100 0.0185 0.0430 <tt>Class C Shares assuming redemption at end of period</tt> 0.0085 <tt>C</tt> 0.0100 LTMBX 0.0000 588 188 1381 -0.0245 <tt>B</tt> 0.0245 0.0000 1081 <tt>Class B Shares assuming no redemption at end of period</tt> 0.0100 0.0185 0.0430 <tt>Class B Shares assuming redemption at end of period</tt> 0.0085 <tt>B</tt> 0.0400 LTMAX 0.0575 681 1386 -0.0245 <tt>A</tt> 0.0245 0.0000 0.0025 0.0110 0.0355 <tt>Class A Shares</tt> 0.0085 <tt>A</tt> 0.0100 <tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate <br />may indicate higher transaction costs and may result in higher taxes when <br />shares are held in a taxable account. These transaction costs, which are not <br />reflected in "Annual Fund Operating Expenses" or in the "Example," affect the <br />fund's performance.</tt> <div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000038774Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <tt>The fund's investment objective is to seek a high level of total return<br />consistent with its asset allocation until the approximate retirement <br />year in the fund's name; thereafter, the fund will seek total return <br />through a combination of current income and capital appreciation. The <br />asset allocation of the fund will change over time.</tt> <tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt> <tt>The fund is designed to provide diversification among different asset classes<br />for investors with the approximate retirement date in the fund's name. The fund<br />invests substantially all of its assets in other MFS mutual funds, referred to<br />as underlying funds. The underlying funds are selected following a two-stage<br />asset allocation process. The first stage is a strategic asset allocation to<br />establish the percentage of the fund's assets to be invested in the general<br />asset classes of Bond Funds, International Stock Funds, and U.S. Stock Funds, as<br />well as an allocation to underlying funds that have less traditional investment<br />strategies that MFS (Massachusetts Financial Services Company, the fund's<br />investment adviser) believes provide diversification benefits when added to a<br />portfolio consisting of stock and bond funds (referred to as Specialty Funds).<br />The second stage involves the actual selection of underlying funds to represent<br />the asset classes based on underlying fund classifications, historical risk,<br />performance, and other factors. Within the stock fund allocations, MFS seeks to<br />diversify globally (by including domestic and international underlying funds),<br />in terms of market capitalization (by including large, mid, and small<br />capitalization underlying funds) and by style (by including both growth and<br />value underlying funds). Within the bond fund allocation, MFS includes<br />underlying funds with varying degrees of interest rate and credit exposure.<br /><br />As of November 1, 2012, the fund's target allocation among asset classes and the<br />underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;<br />MFS Emerging Markets Debt Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%&#xA0;&#xA0;<br />MFS Global Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%&#xA0;&#xA0;<br />MFS High Income Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%&#xA0;&#xA0;<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%&#xA0;&#xA0;<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%&#xA0;&#xA0;<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;<br />MFS Absolute Return Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0%**<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;26%&#xA0;&#xA0;<br />MFS Emerging Markets Equity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%&#xA0;&#xA0;<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%&#xA0;&#xA0;<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%&#xA0;&#xA0;<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;56%&#xA0;&#xA0;<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12%&#xA0;&#xA0;<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%&#xA0;&#xA0;<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%&#xA0;&#xA0;<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12%&#xA0;&#xA0;<br /><br />*&#xA0;&#xA0;The target asset class and underlying fund allocations presented in the table <br />are rounded.<br /> <br />** Less than 0.5%<br /><br />The asset class allocations, as well as the underlying funds and their target<br />weightings, are based on an allocation strategy designed for investors with the<br />approximate retirement year in the fund's name. Investors should also consider<br />their age, personal circumstances, risk tolerance, and overall investment<br />strategy and allocation. The asset allocation strategy will become increasingly<br />conservative over time.<br /><br />Upon reaching its stated target year, the fund's allocation strategy will be<br />aligned with the allocation strategy of the MFS Lifetime Retirement Income<br />Fund.&#xA0;&#xA0;It is expected that the fund will be combined with the MFS Lifetime<br />Retirement Income Fund within five years of the date that its asset allocation<br />strategy matches the asset allocation strategy of the MFS Lifetime Retirement<br />Income Fund.&#xA0;&#xA0;The chart below illustrates how the asset allocation strategy of<br />the fund will change over time.<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;ASSET CLASS WEIGHTS FOR TARGET DATE FUNDS<br /><br />71% Bond Funds<br />4%&#xA0;&#xA0;Specialty Funds<br />5%&#xA0;&#xA0;International Stock Funds<br />20% U.S. Stock Funds<br /><br /><br />U.S. Stock Funds &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date&#xA0;&#xA0;<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10<br />Asset class weight%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;54.5%&#xA0;&#xA0;52%&#xA0;&#xA0;&#xA0;&#xA0;41%&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20% &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;20%<br /><br /><br />International Stock Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;24%&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;13%&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;5%<br /><br /><br />Specialty Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;9%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;<br /><br /><br />Bond Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12.5%&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;40%&#xA0;&#xA0;&#xA0;&#xA0;60%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;71%</tt> Summary of Key Information Example The annual fund operating expenses are based on estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period. The bar chart and performance table are not included because the fund has not had a full calendar year of operations. Investment Objective As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund, including near or after the target date. Principal Risks Shareholder Fees (fees paid directly from your investment): 2013-10-31 Although your actual costs will likely be higher or lower, under these assumptions your costs would be: Performance Information Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): Portfolio Turnover <tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund, including near or after the target<br />date.&#xA0;&#xA0;There is no guarantee that the fund will provide income at or through<br />retirement. An investment in the fund is not a bank deposit and is not insured<br />or guaranteed by the Federal Deposit Insurance Corporation or any other<br />governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /><br />Underlying Funds Risk:&#xA0;&#xA0;MFS' strategy of investing in underlying funds exposes<br />the fund to the risks of the underlying funds. Each underlying fund pursues its<br />own investment objective and strategy and may not achieve its objective.<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline significantly <br />in response to issuer, market, economic, industry, political, regulatory, geopolitical, <br />and other conditions, as well as to investor perceptions of these conditions. The <br />price of an equity security can decrease significantly in response to these <br />conditions, and these conditions can affect a single issuer or type of security, <br />issuers within a broad market sector, industry or geographic region, or the market <br />in general.<br /><br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets, greater custody<br />and operational risk, and less developed legal, regulatory, and accounting<br />systems, and greater political, social, and economic instability than developed<br />markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /><br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /><br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /><br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about <br />the issuer, or the market or economy in general, than higher quality debt instruments.<br /><br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. If <br />inflation is negative, principal and income can both decline.<br /><br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /><br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk: The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real <br />estate and the real estate industry in general. These include risks related to <br />general, regional and local economic conditions; fluctuations in interest rates; <br />property tax rates, zoning laws, environmental regulations and other governmental <br />action; cash flow dependency; increased operating expenses; lack of availability <br />of mortgage funds; losses due to natural disasters; overbuilding; losses due to <br />casualty or condemnation; changes in property values and rental rates; and other <br />factors. The securities of smaller real estate-related issuers can be more volatile <br />and less liquid than securities of larger issuers and their issuers can have more <br />limited financial resources.<br /><br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /><br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt> Fees and Expenses Principal Investment Strategies <tt>The bar chart and performance table are not included because the fund has not<br />had a full calendar year of operations.</tt> <tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. The annual fund operating expenses are based on<br />estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current<br />fiscal year expressed as a percentage of the fund's estimated average net assets<br />during the period.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-13 of<br />the fund's statement of additional information Part I.</tt> <div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000038774Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. <div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000038774Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000038774Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> LFEUX 0.0000 86 590 -0.0152 <tt>R4</tt> 0.0152 0.0000 0.0000 0.0084 0.0236 <tt>Class R4 Shares</tt> 0.0084 <tt>ALL R</tt> 0.0000 LFETX 0.0000 111 667 -0.0152 <tt>R3</tt> 0.0152 0.0000 0.0025 0.0109 0.0261 <tt>Class R3 Shares</tt> 0.0084 <tt>ALL R</tt> 0.0000 LFESX 0.0000 136 742 -0.0152 <tt>R2</tt> 0.0152 0.0000 0.0050 0.0134 0.0286 <tt>Class R2 Shares</tt> 0.0084 <tt>ALL R</tt> 0.0000 LFERX 0.0000 187 892 -0.0152 <tt>R1</tt> 0.0152 0.0000 0.0100 0.0184 0.0336 <tt>Class R1 Shares</tt> 0.0084 <tt>ALL R</tt> 0.0000 LFEDX 0.0000 86 590 -0.0152 <tt>I</tt> 0.0152 0.0000 0.0000 0.0084 0.0236 <tt>Class I Shares</tt> 0.0084 <tt>I</tt> 0.0000 LFECX 0.0000 287 187 892 -0.0152 <tt>C</tt> 0.0152 0.0000 892 <tt>Class C Shares assuming no redemption at end of period</tt> 0.0100 0.0184 0.0336 <tt>Class C Shares assuming redemption at end of period</tt> 0.0084 <tt>C</tt> 0.0100 LFEBX 0.0000 587 187 1192 -0.0152 <tt>B</tt> 0.0152 0.0000 892 <tt>Class B Shares assuming no redemption at end of period</tt> 0.0100 0.0184 0.0336 <tt>Class B Shares assuming redemption at end of period</tt> 0.0084 <tt>B</tt> 0.0400 LFEAX 0.0575 680 1203 -0.0152 <tt>A</tt> 0.0152 0.0000 0.0025 0.0109 0.0261 <tt>Class A Shares</tt> 0.0084 <tt>A</tt> 0.0100 <tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate may<br />indicate higher transaction costs and may result in higher taxes when shares are<br />held in a taxable account. These transaction costs, which are not reflected in<br />"Annual Fund Operating Expenses" or in the "Example," affect the fund's<br />performance.</tt> <div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000038773Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <tt>The fund's investment objective is to seek a high level of total return<br />consistent with its asset allocation until the approximate retirement <br />year in the fund's name; thereafter, the fund will seek total return <br />through a combination of current income and capital appreciation. The <br />asset allocation of the fund will change over time.</tt> <tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt> <tt>The fund is designed to provide diversification among different asset classes<br />for investors with the approximate retirement date in the fund's name. The fund<br />invests substantially all of its assets in other MFS mutual funds, referred to<br />as underlying funds. The underlying funds are selected following a two-stage<br />asset allocation process. The first stage is a strategic asset allocation to<br />establish the percentage of the fund's assets to be invested in the general<br />asset classes of Bond Funds, International Stock Funds, and U.S. Stock Funds, as<br />well as an allocation to underlying funds that have less traditional investment<br />strategies that MFS (Massachusetts Financial Services Company, the fund's<br />investment adviser) believes provide diversification benefits when added to a<br />portfolio consisting of stock and bond funds (referred to as Specialty Funds).<br />The second stage involves the actual selection of underlying funds to represent<br />the asset classes based on underlying fund classifications, historical risk,<br />performance, and other factors. Within the stock fund allocations, MFS seeks to<br />diversify globally (by including domestic and international underlying funds),<br />in terms of market capitalization (by including large, mid, and small<br />capitalization underlying funds) and by style (by including both growth and<br />value underlying funds). Within the bond fund allocation, MFS includes<br />underlying funds with varying degrees of interest rate and credit exposure.<br /><br />As of November 1, 2012, the fund's target allocation among asset classes and the<br />underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;28%<br />MFS Emerging Markets Debt Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />MFS Global Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Government Securities Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS High Income Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS Absolute Return Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;3%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;17%<br />MFS Emerging Markets Equity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS International New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;47%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br /><br />*&#xA0;&#xA0;The target asset class and underlying fund allocations presented in the table<br />are rounded.<br /><br />The asset class allocations, as well as the underlying funds and their target<br />weightings, are based on an allocation strategy designed for investors with the<br />approximate retirement year in the fund's name. Investors should also consider<br />their age, personal circumstances, risk tolerance, and overall investment<br />strategy and allocation. The asset allocation strategy will become increasingly<br />conservative over time.<br /><br />Upon reaching its stated target year, the fund's allocation strategy will be<br />aligned with the allocation strategy of the MFS Lifetime Retirement Income<br />Fund.&#xA0;&#xA0;It is expected that the fund will be combined with the MFS Lifetime<br />Retirement Income Fund within five years of the date that its asset allocation<br />strategy matches the asset allocation strategy of the MFS Lifetime Retirement<br />Income Fund.&#xA0;&#xA0;The chart below illustrates how the asset allocation strategy of<br />the fund will change over time.<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;ASSET CLASS WEIGHTS FOR TARGET DATE FUNDS<br /><br />71% Bond Funds<br />4%&#xA0;&#xA0;Specialty Funds<br />5%&#xA0;&#xA0;International Stock Funds<br />20% U.S. Stock Funds<br /><br /><br />U.S. Stock Funds &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date&#xA0;&#xA0;<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10<br />Asset class weight%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;54.5%&#xA0;&#xA0;52%&#xA0;&#xA0;&#xA0;&#xA0;41%&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20% &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;20%<br /><br /><br />International Stock Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;24%&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;13%&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;5%<br /><br /><br />Specialty Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;9%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;<br /><br /><br />Bond Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12.5%&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;40%&#xA0;&#xA0;&#xA0;&#xA0;60%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;71%</tt> Summary of Key Information You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds. Example The annual fund operating expenses are based on estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period. The bar chart and performance table are not included because the fund has not had a full calendar year of operations. Investment Objective As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund, including near or after the target date. Principal Risks Shareholder Fees (fees paid directly from your investment): 2013-10-31 Although your actual costs will likely be higher or lower, under these assumptions your costs would be: Performance Information 50000 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): Portfolio Turnover <tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund, including near or after the target date.&#xA0;&#xA0;<br />There is no guarantee that the fund will provide income at or through retirement. <br />An investment in the fund is not a bank deposit and is not insured or guaranteed <br />by the Federal Deposit Insurance Corporation or any other governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /><br />Underlying Funds Risk:&#xA0;&#xA0;MFS' strategy of investing in underlying funds exposes<br />the fund to the risks of the underlying funds. Each underlying fund pursues its<br />own investment objective and strategy and may not achieve its objective.<br /><br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline significantly <br />in response to issuer, market, economic, industry, political, regulatory, geopolitical, <br />and other conditions, as well as to investor perceptions of these conditions. The <br />price of an equity security can decrease significantly in response to these <br />conditions, and these conditions can affect a single issuer or type of security, <br />issuers within a broad market sector, industry or geographic region, or the market <br />in general.<br /><br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets, greater custody<br />and operational risk, and less developed legal, regulatory, and accounting<br />systems, and greater political, social, and economic instability than developed<br />markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /><br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /><br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /><br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about <br />the issuer, or the market or economy in general, than higher quality debt <br />instruments.<br /><br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. If <br />inflation is negative, principal and income can both decline.<br /><br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and significantly <br />affected by adverse tax or court rulings, legislative or political changes, changes in <br />specific or general market and economic conditions, and the financial condition of <br />municipal issuers and insurers. Because many municipal instruments are issued to <br />finance similar projects, conditions in these industries can significantly affect the <br />fund and the overall municipal market.<br /><br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk: The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real estate <br />and the real estate industry in general. These include risks related to general, <br />regional and local economic conditions; fluctuations in interest rates; property <br />tax rates, zoning laws, environmental regulations and other governmental action; <br />cash flow dependency; increased operating expenses; lack of availability of mortgage <br />funds; losses due to natural disasters; overbuilding; losses due to casualty or <br />condemnation; changes in property values and rental rates; and other factors.&#xA0;&#xA0;The <br />securities of smaller real estate-related issuers can be more volatile and less <br />liquid than securities of larger issuers and their issuers can have more limited <br />financial resources.<br /><br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /><br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt> Fees and Expenses Principal Investment Strategies <tt>The bar chart and performance table are not included because the fund has not<br />had a full calendar year of operations.</tt> <tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. The annual fund operating expenses are based on<br />estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current<br />fiscal year expressed as a percentage of the fund's estimated average net assets<br />during the period.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-13 of<br />the fund's statement of additional information Part I.</tt> <div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000038773Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. <div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000038773Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000038773Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> LTTAX 0.0575 675 1187 -0.0151 <tt>A</tt> 0.0151 0.0000 0.0025 0.0104 0.0255 <tt>Class A Shares</tt> 0.0079 <tt>A</tt> 0.0100 LTTUX 0.0000 81 573 -0.0151 <tt>R4</tt> 0.0151 0.0000 0.0000 0.0079 0.0230 <tt>Class R4 Shares</tt> 0.0079 <tt>ALL R</tt> 0.0000 LTTTX 0.0000 106 649 -0.0151 <tt>R3</tt> 0.0151 0.0000 0.0025 0.0104 0.0255 <tt>Class R3 Shares</tt> 0.0079 <tt>ALL R</tt> 0.0000 LTTSX 0.0000 131 725 -0.0151 <tt>R2</tt> 0.0151 0.0000 0.0050 0.0129 0.0280 <tt>Class R2 Shares</tt> 0.0079 <tt>ALL R</tt> 0.0000 LTTRX 0.0000 182 875 -0.0151 <tt>R1</tt> 0.0151 0.0000 0.0100 0.0179 0.0330 <tt>Class R1 Shares</tt> 0.0079 <tt>ALL R</tt> 0.0000 LTTIX 0.0000 81 573 -0.0151 <tt>I</tt> 0.0151 0.0000 0.0000 0.0079 0.0230 <tt>Class I Shares</tt> 0.0079 <tt>I</tt> 0.0000 LTTCX 0.0000 282 182 875 -0.0151 <tt>C</tt> 0.0151 0.0000 875 <tt>Class C Shares assuming no redemption at end of period</tt> 0.0100 0.0179 0.0330 <tt>Class C Shares assuming redemption at end of period</tt> 0.0079 <tt>C</tt> 0.0100 LTTBX 0.0000 582 182 1175 -0.0151 <tt>B</tt> 0.0151 0.0000 875 <tt>Class B Shares assuming no redemption at end of period</tt> 0.0100 0.0179 0.0330 <tt>Class B Shares assuming redemption at end of period</tt> 0.0079 <tt>B</tt> 0.0400 <tt>The fund pays transaction costs, such as commissions, when it buys and sells<br />securities (or "turns over" its portfolio). A higher portfolio turnover rate <br />may indicate higher transaction costs and may result in higher taxes when <br />shares are held in a taxable account. These transaction costs, which are not <br />reflected in "Annual Fund Operating Expenses" or in the "Example," affect the <br />fund's performance.</tt> <div style="display:none">~ http://www.mfs.com/role/ExpenseExample_S000038772Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <tt>The fund's investment objective is to seek a high level of total return<br />consistent with its asset allocation until the approximate retirement <br />year in the fund's name; thereafter, the fund will seek total return <br />through a combination of current income and capital appreciation. The <br />asset allocation of the fund will change over time.</tt> <tt>This example is intended to help you compare the cost of investing in the fund<br />with the cost of investing in other mutual funds.<br /><br />The example assumes that: you invest $10,000 in the fund for the time periods<br />indicated and you redeem your shares at the end of the time periods (unless<br />otherwise indicated); your investment has a 5% return each year; and the fund's<br />operating expenses remain the same.</tt> <tt>The fund is designed to provide diversification among different asset classes<br />for investors with the approximate retirement date in the fund's name. The fund<br />invests substantially all of its assets in other MFS mutual funds, referred to<br />as underlying funds. The underlying funds are selected following a two-stage<br />asset allocation process. The first stage is a strategic asset allocation to<br />establish the percentage of the fund's assets to be invested in the general<br />asset classes of Bond Funds, International Stock Funds, and U.S. Stock Funds, as<br />well as an allocation to underlying funds that have less traditional investment<br />strategies that MFS (Massachusetts Financial Services Company, the fund's<br />investment adviser) believes provide diversification benefits when added to a<br />portfolio consisting of stock and bond funds (referred to as Specialty Funds).<br />The second stage involves the actual selection of underlying funds to represent<br />the asset classes based on underlying fund classifications, historical risk,<br />performance, and other factors. Within the stock fund allocations, MFS seeks to<br />diversify globally (by including domestic and international underlying funds),<br />in terms of market capitalization (by including large, mid, and small<br />capitalization underlying funds) and by style (by including both growth and<br />value underlying funds). Within the bond fund allocation, MFS includes<br />underlying funds with varying degrees of interest rate and credit exposure.<br /><br />As of November 1, 2012, the fund's target allocation among asset classes and the<br />underlying funds was:<br /><br />Bond Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;65%<br />MFS Emerging Markets Debt Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS Global Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Government Securities Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10%<br />MFS High Income Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Inflation-Adjusted Bond Fund&#xA0;&#xA0;&#xA0;10%<br />MFS Limited Maturity Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;14%<br />MFS Research Bond Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;19%<br />Specialty Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Absolute Return Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS Commodity Strategy Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS Global Real Estate Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />International Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;7%<br />MFS International Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS International Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;2%<br />MFS Research International Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />U.S. Stock Funds:&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25%<br />MFS Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Mid Cap Growth Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS Mid Cap Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%<br />MFS New Discovery Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS New Discovery Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;1%<br />MFS Research Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br />MFS Value Fund&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%<br /> <br />* The target asset class and underlying fund allocations presented in the table<br />are rounded.<br /><br />The asset class allocations, as well as the underlying funds and their target<br />weightings, are based on an allocation strategy designed for investors with the<br />approximate retirement year in the fund's name. Investors should also consider<br />their age, personal circumstances, risk tolerance, and overall investment<br />strategy and allocation. The asset allocation strategy will become increasingly<br />conservative over time.<br /><br />Upon reaching its stated target year, the fund's allocation strategy will be<br />aligned with the allocation strategy of the MFS Lifetime Retirement Income<br />Fund.&#xA0;&#xA0;It is expected that the fund will be combined with the MFS Lifetime<br />Retirement Income Fund within five years of the date that its asset allocation<br />strategy matches the asset allocation strategy of the MFS Lifetime Retirement<br />Income Fund.&#xA0;&#xA0;The chart below illustrates how the asset allocation strategy of<br />the fund will change over time.<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;ASSET CLASS WEIGHTS FOR TARGET DATE FUNDS<br /><br />71% Bond Funds<br />4%&#xA0;&#xA0;Specialty Funds<br />5%&#xA0;&#xA0;International Stock Funds<br />20% U.S. Stock Funds<br /><br /><br />U.S. Stock Funds &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date&#xA0;&#xA0;<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10<br />Asset class weight%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;57%&#xA0;&#xA0;&#xA0;&#xA0;54.5%&#xA0;&#xA0;52%&#xA0;&#xA0;&#xA0;&#xA0;41%&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20% &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;20%<br /><br /><br />International Stock Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br /><br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;28%&#xA0;&#xA0;&#xA0;&#xA0;24%&#xA0;&#xA0;&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;13%&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;5%<br /><br /><br />Specialty Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;10%&#xA0;&#xA0;&#xA0;&#xA0;9%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;8%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;6%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;&#xA0;&#xA0;4%&#xA0;&#xA0;<br /><br /><br />Bond Funds&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years Before Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Target Date&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;Years After Target Date<br />&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;55&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;50&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;45&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;40&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;35&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;30&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;25&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;20&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;15&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;0&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;10&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;<br />Asset class weight%&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;5%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;12.5%&#xA0;&#xA0;20%&#xA0;&#xA0;&#xA0;&#xA0;40%&#xA0;&#xA0;&#xA0;&#xA0;60%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;71%&#xA0;&#xA0;&#xA0;&#xA0;71%</tt> Summary of Key Information You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds. Example The annual fund operating expenses are based on estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period. The bar chart and performance table are not included because the fund has not had a full calendar year of operations. Investment Objective As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund, including near or after the target date. Principal Risks Shareholder Fees (fees paid directly from your investment): 2013-10-31 Although your actual costs will likely be higher or lower, under these assumptions your costs would be: Performance Information 50000 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): Portfolio Turnover <tt>As with any mutual fund, the fund may not achieve its objective and/or you could<br />lose money on your investment in the fund, including near or after the target<br />date.&#xA0;&#xA0;There is no guarantee that the fund will provide income at or through<br />retirement. An investment in the fund is not a bank deposit and is not insured<br />or guaranteed by the Federal Deposit Insurance Corporation or any other<br />governmental agency.<br /><br />The principal risks of investing in the fund are:<br /><br />Investment Selection and Allocation Risk:&#xA0;&#xA0;MFS' investment analysis, its<br />selection of investments, and its assessment of the risk/return potential of<br />asset classes and underlying funds may not produce the intended results and/or<br />can lead to an investment focus that results in the fund underperforming other<br />funds with similar investment strategies and/or underperforming the markets in<br />which the fund invests.<br /><br />Underlying Funds Risk:&#xA0;&#xA0;MFS' strategy of investing in underlying funds exposes<br />the fund to the risks of the underlying funds. Each underlying fund pursues its<br />own investment objective and strategy and may not achieve its objective.<br /><br />Interest Rate Risk:&#xA0;&#xA0;The price of a debt instrument falls when interest rates<br />rise and rises when interest rates fall. Instruments with longer maturities, or<br />that do not pay current interest, are more sensitive to interest rate changes.<br /><br />Credit Risk:&#xA0;&#xA0;The price of a debt instrument depends, in part, on the credit<br />quality of the issuer, borrower, counterparty, or underlying collateral or<br />assets and the terms of the instrument. The price of a debt instrument can<br />decline in response to changes in the financial condition of the issuer,<br />borrower, counterparty, or underlying collateral or assets, or changes in<br />specific or general market, economic, industry, political, regulatory,<br />geopolitical, or other conditions.<br /><br />Lower quality debt instruments (commonly referred to as "high yield securities"<br />or "junk bonds") can involve a substantially greater risk of default or can<br />already be in default, and their values can decline significantly. Lower quality<br />debt instruments are regarded as having predominantly speculative characteristics. <br />Lower quality debt instruments tend to be more sensitive to adverse news about <br />the issuer, or the market or economy in general, than higher quality debt <br />instruments.<br /><br />Foreign and Emerging Markets Risk:&#xA0;&#xA0;Exposure to foreign markets, especially<br />emerging markets, through issuers or currencies can involve additional risks<br />relating to market, economic, political, regulatory, geopolitical, or other<br />conditions. These factors can make foreign investments, especially those in<br />emerging markets, more volatile and less liquid than U.S. investments. In<br />addition, foreign markets can react differently to these conditions than the<br />U.S. market. Emerging markets can have less developed markets, greater custody<br />and operational risk, and less developed legal, regulatory, and accounting<br />systems, and greater political, social, and economic instability than developed<br />markets.<br /><br />Currency Risk:&#xA0;&#xA0;The value of foreign currencies relative to the U.S. dollar<br />fluctuates in response to market, economic, political, regulatory, geopolitical<br />or other conditions, and a decline in the value of a foreign currency versus the<br />U.S. dollar reduces the value in U.S. dollars of investments denominated in that<br />foreign currency.<br /><br />Prepayment/Extension Risk:&#xA0;&#xA0;Instruments subject to prepayment and/or extension<br />can reduce the potential for gain for the instrument's holders if the instrument<br />is prepaid and increase the potential for loss if the maturity of the instrument<br />is extended.<br /><br />Inflation-Adjusted Debt Instruments Risk:&#xA0;&#xA0;Interest payments on inflation-adjusted <br />debt instruments can be unpredictable and vary based on the level of inflation. <br />If inflation is negative, principal and income can both decline.<br /><br />Municipal Risk:&#xA0;&#xA0;The price of a municipal instrument can be volatile and<br />significantly affected by adverse tax or court rulings, legislative or political<br />changes, changes in specific or general market and economic conditions, and the<br />financial condition of municipal issuers and insurers. Because many municipal<br />instruments are issued to finance similar projects, conditions in these<br />industries can significantly affect the fund and the overall municipal market.<br /><br />Commodity Risk:&#xA0;&#xA0;The value of commodities may be more volatile than the value of<br />equity securities or debt instruments and their value may be affected by changes<br />in overall market movements, commodity index volatility, changes in interest<br />rates, or factors affecting a particular industry or commodity. The price of a<br />commodity may be affected by demand/supply imbalances in the market for the<br />commodity.<br /><br />Real Estate-Related Investment Risk: The risks of investing in real estate-related <br />securities include certain risks associated with the direct ownership of real <br />estate and the real estate industry in general. These include risks related to <br />general, regional and local economic conditions; fluctuations in interest rates; <br />property tax rates, zoning laws, environmental regulations and other governmental <br />action; cash flow dependency; increased operating expenses; lack of availability <br />of mortgage funds; losses due to natural disasters; overbuilding; losses due to <br />casualty or condemnation; changes in property values and rental rates; and other <br />factors.&#xA0;&#xA0;The securities of smaller real estate-related issuers can be more <br />volatile and less liquid than securities of larger issuers and their issuers can <br />have more limited financial resources.<br /> <br />Stock Market/Company Risk:&#xA0;&#xA0;Stock markets are volatile and can decline<br />significantly in response to issuer, market, economic, industry, political,<br />regulatory, geopolitical, and other conditions, as well as to investor<br />perceptions of these conditions. The price of an equity security can decrease<br />significantly in response to these conditions, and these conditions can affect a<br />single issuer or type of security, issuers within a broad market sector,<br />industry or geographic region, or the market in general.<br /><br />Derivatives Risk:&#xA0;&#xA0;Derivatives can be highly volatile and involve risks in<br />addition to the risks of the underlying indicator(s) on which the derivative is<br />based. Gains or losses from derivatives can be substantially greater than the<br />derivatives' original cost.&#xA0;&#xA0;Derivatives can involve leverage.<br /><br />Leveraging Risk:&#xA0;&#xA0;Leverage involves investment exposure in an amount exceeding<br />the initial investment. Leverage can cause increased volatility by magnifying<br />gains or losses.<br /><br />Counterparty and Third Party Risk:&#xA0;&#xA0;Transactions involving a counterparty or<br />third party other than the issuer of the instrument are subject to the credit<br />risk of the counterparty or third party, and to the counterparty's or third<br />party's ability to perform in accordance with the terms of the transaction.<br /><br />Liquidity Risk:&#xA0;&#xA0;It may not be possible to sell certain investments, types of<br />investments, and/or segments of the market at any particular time or at an<br />acceptable price.</tt> Fees and Expenses Principal Investment Strategies <tt>The bar chart and performance table are not included because the fund has not<br />had a full calendar year of operations.</tt> <tt>This table describes the fees and expenses that you may pay when you buy and<br />hold shares of the fund. The annual fund operating expenses are based on<br />estimated "Other Expenses" and "Acquired Fund Fees and Expenses" for the current<br />fiscal year expressed as a percentage of the fund's estimated average net assets<br />during the period.<br /><br />You may qualify for sales charge reductions if you and certain members of your<br />family invest, or agree to invest in the future, at least $50,000 in MFS Funds.<br />More information about these and other waivers and reductions is available from<br />your financial intermediary and in "Sales Charges and Waivers or Reductions" on<br />page 11 of the fund's prospectus and "Waivers of Sales Charges" on page I-13 of<br />the fund's statement of additional information Part I.</tt> <div style="display:none">~ http://www.mfs.com/role/OperatingExpensesData_S000038772Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. <div style="display:none">~ http://www.mfs.com/role/ExpenseExampleNoRedemption_S000038772Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> <div style="display:none">~ http://www.mfs.com/role/ShareholderFeesData_S000038772Member column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~</div> LFTUX 0.0000 69 729 -0.0242 <tt>R4</tt> 0.0242 0.0000 0.0000 0.0068 0.0310 <tt>Class R4 Shares</tt> 0.0068 <tt>ALL R</tt> 0.0000 LFTTX 0.0000 95 804 -0.0242 <tt>R3</tt> 0.0242 0.0000 0.0025 0.0093 0.0335 <tt>Class R3 Shares</tt> 0.0068 <tt>ALL R</tt> 0.0000 LFTSX 0.0000 120 878 -0.0242 <tt>R2</tt> 0.0242 0.0000 0.0050 0.0118 0.0360 <tt>Class R2 Shares</tt> 0.0068 <tt>ALL R</tt> 0.0000 LFTRX 0.0000 171 1026 -0.0242 <tt>R1</tt> 0.0242 0.0000 0.0100 0.0168 0.0410 <tt>Class R1 Shares</tt> 0.0068 <tt>ALL R</tt> 0.0000 LFTIX 0.0000 69 729 -0.0242 <tt>I</tt> 0.0242 0.0000 0.0000 0.0068 0.0310 <tt>Class I Shares</tt> 0.0068 <tt>I</tt> 0.0000 LFTCX 0.0000 271 171 1026 -0.0242 <tt>C</tt> 0.0242 0.0000 1026 <tt>Class C Shares assuming no redemption at end of period</tt> 0.0100 0.0168 0.0410 <tt>Class C Shares assuming redemption at end of period</tt> 0.0068 <tt>C</tt> 0.0100 LFTBX 0.0000 571 171 1326 -0.0242 <tt>B</tt> 0.0242 0.0000 1026 <tt>Class B Shares assuming no redemption at end of period</tt> 0.0100 0.0168 0.0410 <tt>Class B Shares assuming redemption at end of period</tt> 0.0068 <tt>B</tt> 0.0400 LFTDX 0.0575 664 1333 -0.0242 <tt>A</tt> 0.0242 0.0000 0.0025 0.0093 0.0335 <tt>Class A Shares</tt> 0.0068 <tt>A</tt> 0.0100 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119415Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119416Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119417Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119418Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119419Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119420Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119421Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Memberck0001330967:C000119422Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038772Memberck0001330967:S000038772Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119423Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119424Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119425Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119426Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119427Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119428Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119429Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Memberck0001330967:C000119430Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038773Memberck0001330967:S000038773Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119431Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119432Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119433Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119434Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119435Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119436Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119437Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Memberck0001330967:C000119438Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038774Memberck0001330967:S000038774Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119439Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119440Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119441Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119442Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119443Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119444Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119445Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Memberck0001330967:C000119446Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038775Memberck0001330967:S000038775Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119447Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119448Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119449Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119450Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119451Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119452Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119453Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Memberck0001330967:C000119454Member 2012-11-01 2012-11-01 0001330967 ck0001330967:SummaryS000038776Memberck0001330967:S000038776Member 2012-11-01 2012-11-01 0001330967 2012-11-01 2012-11-01 iso4217:USD pure On shares purchased without an initial sales charge and redeemed within 18 months of purchase for shares purchased on or after August 1, 2012, and within 24 months of purchase for shares purchased prior to August 1, 2012. Massachusetts Financial Services Company has agreed in writing to bear the fund's expenses, excluding management fees, distribution and service fees, interest, taxes, extraordinary expenses, brokerage and transaction costs, investment-related expenses, and fees and expenses associated with investments in investment companies and other similar investment vehicles, such that "Other Expenses" do not exceed 0.00% of the fund's average daily net assets annually for each class of shares. This agreement will continue until at least October 31, 2013, after which Massachusetts Financial Services Company may increase such expense limitation to 0.10% of the fund's average daily net assets annually for each class of shares without a vote of the fund's Board of Trustees. Any increase above 0.10% would require a vote of the fund's Board of Trustees. EX-101.SCH 3 ck0001330967-20121026.xsd XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT 00101 - Document - Document And Entity Information {Elements} link:calculationLink link:presentationLink link:definitionLink 01102 - Document - Risk/Return Summary {Unlabeled} (MFS Lifetime 2015 Fund) link:calculationLink link:presentationLink link:definitionLink 01103 - Schedule - Shareholder Fees link:calculationLink link:presentationLink link:definitionLink 01104 - Schedule - Annual Fund Operating Expenses link:calculationLink link:presentationLink link:definitionLink 01105 - Schedule - Expense Example {Transposed} link:calculationLink link:presentationLink link:definitionLink 01106 - Schedule - Expense Example, No Redemption {Transposed} link:calculationLink link:presentationLink link:definitionLink 06108 - Document - Risk/Return Summary {Unlabeled} (MFS Lifetime 2025 Fund) link:calculationLink link:presentationLink link:definitionLink 06109 - Schedule - Shareholder Fees link:calculationLink link:presentationLink link:definitionLink 06110 - Schedule - Annual Fund Operating Expenses link:calculationLink link:presentationLink link:definitionLink 06111 - Schedule - Expense Example {Transposed} link:calculationLink link:presentationLink link:definitionLink 06112 - Schedule - Expense Example, No Redemption {Transposed} link:calculationLink link:presentationLink link:definitionLink 06113 - Disclosure - Risk/Return Detail Data {Elements} (MFS Lifetime 2025 Fund) link:calculationLink link:presentationLink link:definitionLink 06114 - Document - Risk/Return Summary {Unlabeled} (MFS Lifetime 2035 Fund) link:calculationLink link:presentationLink link:definitionLink 06115 - Schedule - Shareholder Fees link:calculationLink link:presentationLink link:definitionLink 06116 - Schedule - Annual Fund Operating Expenses link:calculationLink link:presentationLink link:definitionLink 06117 - Schedule - Expense Example {Transposed} link:calculationLink link:presentationLink link:definitionLink 06118 - Schedule - Expense Example, No Redemption {Transposed} link:calculationLink link:presentationLink link:definitionLink 06119 - Disclosure - Risk/Return Detail Data {Elements} (MFS Lifetime 2035 Fund) link:calculationLink link:presentationLink link:definitionLink 06120 - Document - Risk/Return Summary {Unlabeled} (MFS Lifetime 2045 Fund) link:calculationLink link:presentationLink link:definitionLink 06121 - Schedule - Shareholder Fees link:calculationLink link:presentationLink link:definitionLink 06122 - Schedule - Annual Fund Operating Expenses link:calculationLink link:presentationLink link:definitionLink 06123 - Schedule - Expense Example {Transposed} link:calculationLink link:presentationLink link:definitionLink 06124 - Schedule - Expense Example, No Redemption {Transposed} link:calculationLink link:presentationLink link:definitionLink 06125 - Disclosure - Risk/Return Detail Data {Elements} (MFS Lifetime 2045 Fund) link:calculationLink link:presentationLink link:definitionLink 06126 - Document - Risk/Return Summary {Unlabeled} (MFS Lifetime 2055 Fund) link:calculationLink link:presentationLink link:definitionLink 06127 - Schedule - Shareholder Fees link:calculationLink link:presentationLink link:definitionLink 06128 - Schedule - Annual Fund Operating Expenses link:calculationLink link:presentationLink link:definitionLink 06129 - Schedule - Expense Example {Transposed} link:calculationLink link:presentationLink link:definitionLink 06130 - Schedule - Expense Example, No Redemption {Transposed} link:calculationLink link:presentationLink link:definitionLink 06131 - Disclosure - Risk/Return Detail Data {Elements} (MFS Lifetime 2055 Fund) link:calculationLink link:presentationLink link:definitionLink EX-101.CAL 4 ck0001330967-20121026_cal.xml XBRL TAXONOMY EXTENSION CALCULATION LINKBASE DOCUMENT EX-101.DEF 5 ck0001330967-20121026_def.xml XBRL TAXONOMY EXTENSION DEFINITION LINKBASE DOCUMENT EX-101.LAB 6 ck0001330967-20121026_lab.xml XBRL TAXONOMY EXTENSION LABELS LINKBASE DOCUMENT EX-101.PRE 7 ck0001330967-20121026_pre.xml XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT