497

Incorporated herein by reference is a supplement to the prospectus of MFS Global Total Return Fund, a series of MFS Series Trust VI (File No. 33-34502), filed pursuant to Rule 497(e) under the Securities Act of 1933, as amended, on May 30, 2012 (SEC Accession No 0000912938-12-000230).

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Prospectus Date

rr_ProspectusDate

Feb. 28, 2012

MFS Global Total Return Fund (Prospectus Summary): | MFS Global Total Return Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return, Heading

rr_RiskReturnHeading

MFS® Global Total Return Fund  

Supplement Text

ck0000863032_SupplementTextBlock

SUPPLEMENT TO PROSPECTUS

The date of this supplement is May 30, 2012.

MFS® Global Total Return Fund

The ticker symbol chart located on the front cover page is restated in its entirety as follows:

CLASS	TICKER SYMBOL
Class A	MFWTX
Class B	MFWBX
Class C	MFWCX
Class I	MFWIX
Class R1	MFWGX
Class R2	MGBRX
Class R3	MFWHX
Class R4	MFWJX
Class R5	MFWLX

The sub-sections entitled “Fees and Expenses” and “Example” beneath the main heading "Summary of Key Information" are restated in their entirety as follows:

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

2014-02-28  

Expense Breakpoint, Discounts

rr_ExpenseBreakpointDiscounts

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.

Expense, Heading

rr_ExpenseHeading

Fees and Expenses  

Expense Breakpoint, Minimum Investment Required Amount

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense, Narrative

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay when you buy and hold shares of the fund. The annual fund operating expenses for Class R5 shares are based on estimated "Other Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period.

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. More information about these and other waivers and reductions is available from your financial intermediary and in “Sales Charges and Waivers or Reductions” on page 9 of the fund’s prospectus and “Waivers of Sales Charges” on page I-14 of the fund’s statement of additional information Part I.

Shareholder Fees, Caption

rr_ShareholderFeesCaption

Shareholder Fees (fees paid directly from your investment):  

Operating Expenses, Caption

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):  

Other Expenses, New Fund, Based on Estimates

rr_OtherExpensesNewFundBasedOnEstimates

The annual fund operating expenses for Class R5 shares are based on estimated "Other Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period.

Expense Example, Heading

rr_ExpenseExampleHeading

Example

Expense Example, Narrative

rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.

The example assumes that: you invest $10,000 in the fund for the time periods indicated and you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% return each year; and the fund’s operating expenses remain the same.

Expense Example, By Year, Caption

rr_ExpenseExampleByYearCaption

Although your actual costs will likely be higher or lower, under these assumptions your costs would be:  

BarChartAndPerformanceTableSubHeading

ck0000863032_Barchartandperformancetablesubheading

The paragraph that follows the Class A Bar Chart, and the Performance Table beneath the sub-section entitled "Performance Information" beneath the main heading "Summary of Key Information" are restated in their entirety as follows:

Index No Deduction for Fees, Expenses, Taxes

rr_IndexNoDeductionForFeesExpensesTaxes

Reflects no deduction for fees, expenses or taxes

Bar Chart, Closing

rr_BarChartClosingTextBlock

The total return for the three-month period ended March 31, 2012 was 6.51%. During the period(s) shown in the bar chart, the highest quarterly return was 12.25% (for the calendar quarter ended June 30, 2009) and the lowest quarterly return was (9.94)% (for the calendar quarter ended March 31, 2009).

Performance Table, Heading

rr_PerformanceTableHeading

Performance Table.  

Average Annual Returns, Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns (for the Periods Ended December 31, 2011)  

MFS Global Total Return Fund | A

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWTX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

A

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

^[1]

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

A

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.30%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

1.25%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class A Shares

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

695

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

955

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

1,239

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

2,045

Year to Date Return, Label

rr_YearToDateReturnLabel

The total return for the three-month period ended

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

lowest quarterly return

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

highest quarterly return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2012

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

6.51%

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Mar. 31, 2009

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(9.94%)

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

12.25%

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

A Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(3.67%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.72%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.45%

MFS Global Total Return Fund | A | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

A Shares Returns After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(4.25%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.70%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.19%

MFS Global Total Return Fund | A | After Taxes on Distributions and Sales

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

A Shares Returns After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(2.04%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.09%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.15%

MFS Global Total Return Fund | B

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWBX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

B

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

4.00%

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

B

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.05%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

2.00%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class B Shares assuming redemption at end of period

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

603

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

934

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

1,295

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

2,180

Expense Example, No Redemption, By Year, Column

rr_ExpenseExampleNoRedemptionByYearColumnName

Class B Shares assuming no redemption at end of period

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

203

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

634

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,095

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,180

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

B Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(2.46%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.86%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.51%

MFS Global Total Return Fund | R5

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWLX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

ALL R

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

R5

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.14%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.98%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.04%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

0.94%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class R5 Shares

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

96

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

305

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

535

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

1,195

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

R5 Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.49%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.24%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.43%

MFS Global Total Return Fund | C

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWCX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

C

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

C

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.05%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

2.00%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class C Shares assuming redemption at end of period

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

303

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

634

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

1,095

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

2,372

Expense Example, No Redemption, By Year, Column

rr_ExpenseExampleNoRedemptionByYearColumnName

Class C Shares assuming no redemption at end of period

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

203

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

634

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,095

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,372

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

C Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.56%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.21%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.37%

MFS Global Total Return Fund | I

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWIX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

I

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

I

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.05%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

1.00%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class I Shares

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

102

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

325

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

571

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

1,274

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

I Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.49%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.24%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.43%

MFS Global Total Return Fund | R1

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWGX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

ALL R

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

R1

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.05%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

2.00%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class R1 Shares

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

203

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

634

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

1,095

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

2,372

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

R1 Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.57%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.18%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.26%

MFS Global Total Return Fund | R2

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MGBRX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

ALL R

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

R2

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.55%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

1.50%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class R2 Shares

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

153

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

481

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

836

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

1,838

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

R2 Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.05%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.70%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.76%

MFS Global Total Return Fund | R3

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWHX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

ALL R

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

R3

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.30%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

1.25%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class R3 Shares

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

127

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

403

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

704

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

1,560

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

R3 Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.30%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.95%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.07%

MFS Global Total Return Fund | R4

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

MFWJX

Shareholder Fees, Column Name

rr_ShareholderFeesColumnName

ALL R

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Operating Expenses, Column Name

rr_OperatingExpensesColumnName

R4

Management Fee

rr_ManagementFeesOverAssets

0.84%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.21%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.05%

Fee Reductions and/or Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.05%)

^[2]

Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements

rr_NetExpensesOverAssets

1.00%

Expense Example, By Year, Column

rr_ExpenseExampleByYearColumnName

Class R4 Shares

Expense Example, With Redemption, 1 Year

rr_ExpenseExampleYear01

102

Expense Example, With Redemption, 3 Years

rr_ExpenseExampleYear03

325

Expense Example, With Redemption, 5 Years

rr_ExpenseExampleYear05

571

Expense Example, With Redemption, 10 Years

rr_ExpenseExampleYear10

1,274

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

R4 Shares Returns Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.55%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.20%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.37%

MFS Global Total Return Fund | Index Comparisons (Reflects no deduction for fees, expenses or taxes) MSCI World Index (gross div)

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

Index Comparisons (Reflects no deduction for fees, expenses or taxes) MSCI World Index (gross div)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(5.02%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

(1.82%)

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.15%

MFS Global Total Return Fund | Index Comparisons (Reflects no deduction for fees, expenses or taxes) Barclays Capital Global Aggregate Bond Index

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

Index Comparisons (Reflects no deduction for fees, expenses or taxes) Barclays Capital Global Aggregate Bond Index

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

5.64%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.46%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.16%

MFS Global Total Return Fund | Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Global Total Return Blended Index (gross div)

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, Label

rr_AverageAnnualReturnLabel

Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Global Total Return Blended Index (gross div)

^[3]

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.62%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.84%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.69%

[1] On shares purchased without an initial sales charge and redeemed within 24 months of purchase.

[2] Massachusetts Financial Services Company has agreed in writing to reduce its management fee to 0.75% of the fund’s average daily net assets annually in excess of $500 million up to $1 billion, and 0.70% of the fund’s average daily net assets annually in excess of $1 billion. This written agreement will remain in effect until modified by the fund’s Board of Trustees, but such agreement will continue until at least February 28, 2014. In addition, Massachusetts Financial Services Company has agreed in writing to bear the fund’s expenses, excluding interest, taxes, extraordinary expenses, brokerage and transaction costs and investment-related expenses (such as interest and borrowing expenses incurred in connection with the fund’s investment activity), such that “Total Annual Fund Operating Expenses” do not exceed 1.25% of the fund’s average daily net assets annually for each of Class A and Class R3 shares, 2.00% of the fund’s average daily net assets annually for each of Class B, Class C and Class R1 shares, 1.00% of the fund’s average daily net assets annually for each of Class I and Class R4 shares, 1.50% of the fund’s average daily net assets annually for Class R2 shares, and 0.94% of the fund’s average daily net assets annually for Class R5 shares. This written agreement will continue until modified by the fund’s Board of Trustees, but such agreement will continue until at least February 28, 2014.

[3] The MFS Global Total Return Blended Index (gross div) was composed at period end of the following amounts of the following indices: 60% MSCI World Index (gross div) and 40% Barclays Capital Global Aggregate Bond Index.

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MFS Global Total Return Fund (Prospectus Summary): | MFS Global Total Return Fund

MFS® Global Total Return Fund  

SUPPLEMENT TO PROSPECTUS

The date of this supplement is May 30, 2012.

MFS® Global Total Return Fund

The ticker symbol chart located on the front cover page is restated in its entirety as follows:

CLASS	TICKER SYMBOL
Class A	MFWTX
Class B	MFWBX
Class C	MFWCX
Class I	MFWIX
Class R1	MFWGX
Class R2	MGBRX
Class R3	MFWHX
Class R4	MFWJX
Class R5	MFWLX

The sub-sections entitled “Fees and Expenses” and “Example” beneath the main heading "Summary of Key Information" are restated in their entirety as follows:

Fees and Expenses  

This table describes the fees and expenses that you may pay when you buy and hold shares of the fund. The annual fund operating expenses for Class R5 shares are based on estimated "Other Expenses" for the current fiscal year expressed as a percentage of the fund's estimated average net assets during the period.

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. More information about these and other waivers and reductions is available from your financial intermediary and in “Sales Charges and Waivers or Reductions” on page 9 of the fund’s prospectus and “Waivers of Sales Charges” on page I-14 of the fund’s statement of additional information Part I.

Shareholder Fees (fees paid directly from your investment):  

Shareholder Fees MFS Global Total Return Fund	A		B	C	I	R1	R2	R3	R4	R5
Shareholder Fees, Column Name	A		B	C	I	ALL R	ALL R	ALL R	ALL R	ALL R
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.75%		none	none	none	none	none	none	none	none
Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)	1.00%	[1]	4.00%	1.00%	none	none	none	none	none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):  

Annual Fund Operating Expenses MFS Global Total Return Fund		A	B	C	I	R1	R2	R3	R4	R5
Operating Expenses, Column Name		A	B	C	I	R1	R2	R3	R4	R5
Management Fee		0.84%	0.84%	0.84%	0.84%	0.84%	0.84%	0.84%	0.84%	0.84%
Distribution and/or Service (12b-1) Fees		0.25%	1.00%	1.00%	none	1.00%	0.50%	0.25%	none	none
Other Expenses		0.21%	0.21%	0.21%	0.21%	0.21%	0.21%	0.21%	0.21%	0.14%
Total Annual Fund Operating Expenses		1.30%	2.05%	2.05%	1.05%	2.05%	1.55%	1.30%	1.05%	0.98%
Fee Reductions and/or Expense Reimbursements	[1]	(0.05%)	(0.05%)	(0.05%)	(0.05%)	(0.05%)	(0.05%)	(0.05%)	(0.05%)	(0.04%)
Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements		1.25%	2.00%	2.00%	1.00%	2.00%	1.50%	1.25%	1.00%	0.94%

Example

This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.

The example assumes that: you invest $10,000 in the fund for the time periods indicated and you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% return each year; and the fund’s operating expenses remain the same.

Although your actual costs will likely be higher or lower, under these assumptions your costs would be:  

Expense Example MFS Global Total Return Fund (USD $)	Expense Example, By Year, Column	Expense Example, With Redemption, 1 Year	Expense Example, With Redemption, 3 Years	Expense Example, With Redemption, 5 Years	Expense Example, With Redemption, 10 Years
A	Class A Shares	695	955	1,239	2,045
B	Class B Shares assuming redemption at end of period	603	934	1,295	2,180
C	Class C Shares assuming redemption at end of period	303	634	1,095	2,372
I	Class I Shares	102	325	571	1,274
R1	Class R1 Shares	203	634	1,095	2,372
R2	Class R2 Shares	153	481	836	1,838
R3	Class R3 Shares	127	403	704	1,560
R4	Class R4 Shares	102	325	571	1,274
R5	Class R5 Shares	96	305	535	1,195

Expense Example, No Redemption MFS Global Total Return Fund (USD $)	Expense Example, No Redemption, By Year, Column	Expense Example, No Redemption, 1 Year	Expense Example, No Redemption, 3 Years	Expense Example, No Redemption, 5 Years	Expense Example, No Redemption, 10 Years
B	Class B Shares assuming no redemption at end of period	203	634	1,095	2,180
C	Class C Shares assuming no redemption at end of period	203	634	1,095	2,372

The paragraph that follows the Class A Bar Chart, and the Performance Table beneath the sub-section entitled "Performance Information" beneath the main heading "Summary of Key Information" are restated in their entirety as follows:

The total return for the three-month period ended March 31, 2012 was 6.51%. During the period(s) shown in the bar chart, the highest quarterly return was 12.25% (for the calendar quarter ended June 30, 2009) and the lowest quarterly return was (9.94)% (for the calendar quarter ended March 31, 2009).

Performance Table.  

Average Annual Total Returns (for the Periods Ended December 31, 2011)  

Average Annual Total Returns MFS Global Total Return Fund	Average Annual Returns, Label		Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
B	B Shares Returns Before Taxes		(2.46%)	1.86%	6.51%
C	C Shares Returns Before Taxes		0.56%	2.21%	6.37%
I	I Shares Returns Before Taxes		2.49%	3.24%	7.43%
R1	R1 Shares Returns Before Taxes		1.57%	2.18%	6.26%
R2	R2 Shares Returns Before Taxes		2.05%	2.70%	6.76%
R3	R3 Shares Returns Before Taxes		2.30%	2.95%	7.07%
R4	R4 Shares Returns Before Taxes		2.55%	3.20%	7.37%
R5	R5 Shares Returns Before Taxes		2.49%	3.24%	7.43%
A	A Shares Returns Before Taxes		(3.67%)	1.72%	6.45%
A After Taxes on Distributions	A Shares Returns After Taxes on Distributions		(4.25%)	0.70%	5.19%
A After Taxes on Distributions and Sales	A Shares Returns After Taxes on Distributions and Sale of Fund Shares		(2.04%)	1.09%	5.15%
Index Comparisons (Reflects no deduction for fees, expenses or taxes) MSCI World Index (gross div)	Index Comparisons (Reflects no deduction for fees, expenses or taxes) MSCI World Index (gross div)		(5.02%)	(1.82%)	4.15%
Index Comparisons (Reflects no deduction for fees, expenses or taxes) Barclays Capital Global Aggregate Bond Index	Index Comparisons (Reflects no deduction for fees, expenses or taxes) Barclays Capital Global Aggregate Bond Index		5.64%	6.46%	7.16%
Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Global Total Return Blended Index (gross div)	Index Comparisons (Reflects no deduction for fees, expenses or taxes) MFS Global Total Return Blended Index (gross div)	[1]	(0.62%)	1.84%	5.69%

[1] On shares purchased without an initial sales charge and redeemed within 24 months of purchase.

[1] Massachusetts Financial Services Company has agreed in writing to reduce its management fee to 0.75% of the fund’s average daily net assets annually in excess of $500 million up to $1 billion, and 0.70% of the fund’s average daily net assets annually in excess of $1 billion. This written agreement will remain in effect until modified by the fund’s Board of Trustees, but such agreement will continue until at least February 28, 2014. In addition, Massachusetts Financial Services Company has agreed in writing to bear the fund’s expenses, excluding interest, taxes, extraordinary expenses, brokerage and transaction costs and investment-related expenses (such as interest and borrowing expenses incurred in connection with the fund’s investment activity), such that “Total Annual Fund Operating Expenses” do not exceed 1.25% of the fund’s average daily net assets annually for each of Class A and Class R3 shares, 2.00% of the fund’s average daily net assets annually for each of Class B, Class C and Class R1 shares, 1.00% of the fund’s average daily net assets annually for each of Class I and Class R4 shares, 1.50% of the fund’s average daily net assets annually for Class R2 shares, and 0.94% of the fund’s average daily net assets annually for Class R5 shares. This written agreement will continue until modified by the fund’s Board of Trustees, but such agreement will continue until at least February 28, 2014.

[1] The MFS Global Total Return Blended Index (gross div) was composed at period end of the following amounts of the following indices: 60% MSCI World Index (gross div) and 40% Barclays Capital Global Aggregate Bond Index.