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MFS SERIES TRUST XII | MFS® Equity Opportunities Fund

Risk/Return:

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Supplement [Text Block]

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SUPPLEMENT TO THE PROSPECTUS

The date of this supplement is April 10, 2017.

For Certain MFS® Funds

Risk/Return [Heading]

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MFS® Equity Opportunities Fund

Expense Narrative [Text Block]

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Effective immediately, the following sentence is added to the first paragraph in the sub-section entitled “Fees and Expenses” under the main heading entitled “Summary of Key Information”:

Investors may also pay commissions or other fees to their financial intermediary when they buy and hold shares of the fund, which are not reflected below.

1028417 MULTI-SUP-III-041017