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<PAGE> PAGE 21
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<PAGE> PAGE 22
053 C000400 N
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066 F000400 N
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<PAGE> PAGE 23
070 G010400 Y
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070 I020400 N
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070 L020400 Y
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<PAGE> PAGE 24
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SIGNATURE JAMES O.YOST
TITLE ASSISTANT TREASURER
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS OF MFS/FOREIGN & COLONIAL EMERGING MARKETS EQUITY FUND
CLASS A AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
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<NAME> MFS/FOREIGN & COLONIAL EMERGING MARKETS EQUITY FUND CLASS A
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<TABLE> <S> <C>
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<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS OF MFS/FOREIGN & COLONIAL EMERGING MARKETS EQUITY FUND
CLASS B AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
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<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 042
<NAME> MFS/FOREIGN & COLONIAL EMERGING MARKETS EQUITY FUND CLASS B
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<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
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QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
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<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
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<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS OF MFS/FOREIGN & COLONIAL INTL GROWTH FUND CALSS B AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 032
<NAME> MFS/FOREIGN & COLONIAL INTL GROWTH FUND CLASS B
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUL-31-1996
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<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS OF MFS/FOREIGN & COLONIAL INTL GROWTH & INCOME FUND CLASS A
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 021
<NAME> MFS/FOREIGN & COLONIAL INTL GROWTH & INCOME FUND CLASS A
<S> <C>
<PERIOD-TYPE> 6-MOS
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<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
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AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
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<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 022
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<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS OF MFS GOVERNMENT MORTGAGE FUND CLASS A AND IS QUALIFIED
IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 011
<NAME> MFS GOVERNMENT MORTGAGE FUND CLASS A
<S> <C>
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<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 2554040
<TOTAL-LIABILITIES> 2554040
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1353818019
<SHARES-COMMON-STOCK> 86718180
<SHARES-COMMON-PRIOR> 80276379
<ACCUMULATED-NII-CURRENT> 1226928
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (129371822)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 39239212
<NET-ASSETS> 1264912337
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 51123133
<OTHER-INCOME> 0
<EXPENSES-NET> 10535127
<NET-INVESTMENT-INCOME> 40588006
<REALIZED-GAINS-CURRENT> (1861384)
<APPREC-INCREASE-CURRENT> 37124177
<NET-CHANGE-FROM-OPS> 75850799
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 17979617
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 13499049
<NUMBER-OF-SHARES-REDEEMED> 8235491
<SHARES-REINVESTED> 1178243
<NET-CHANGE-IN-ASSETS> (81140460)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (127510438)
<OVERDISTRIB-NII-PRIOR> 121221
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4021633
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 10789961
<AVERAGE-NET-ASSETS> 1304130145
<PER-SHARE-NAV-BEGIN> 6.65
<PER-SHARE-NII> 0.22
<PER-SHARE-GAIN-APPREC> 0.18
<PER-SHARE-DIVIDEND> 0.21
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 6.84
<EXPENSE-RATIO> 1.22
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS OF MFS GOVERNMENT MORTGAGE FUND CLASS B AND IS QUALIFIED
IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 012
<NAME> MFS GOVERNMENT MORTGAGE FUND CLASS B
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUL-31-1996
<PERIOD-END> JAN-31-1996
<INVESTMENTS-AT-COST> 1202544865
<INVESTMENTS-AT-VALUE> 1241784077
<RECEIVABLES> 25490432
<ASSETS-OTHER> 19877
<OTHER-ITEMS-ASSETS> 171991
<TOTAL-ASSETS> 1267466377
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 2554040
<TOTAL-LIABILITIES> 2554040
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1353818019
<SHARES-COMMON-STOCK> 98188401
<SHARES-COMMON-PRIOR> 122148158
<ACCUMULATED-NII-CURRENT> 1226928
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (129371822)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 39239212
<NET-ASSETS> 1264912337
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 51123133
<OTHER-INCOME> 0
<EXPENSES-NET> 10535127
<NET-INVESTMENT-INCOME> 40588006
<REALIZED-GAINS-CURRENT> (1861384)
<APPREC-INCREASE-CURRENT> 37124177
<NET-CHANGE-FROM-OPS> 75850799
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 21260240
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 6837644
<NUMBER-OF-SHARES-REDEEMED> 32297321
<SHARES-REINVESTED> 1499920
<NET-CHANGE-IN-ASSETS> (81140460)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (127510438)
<OVERDISTRIB-NII-PRIOR> 121221
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4021633
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 10789961
<AVERAGE-NET-ASSETS> 1304130145
<PER-SHARE-NAV-BEGIN> 6.65
<PER-SHARE-NII> 0.20
<PER-SHARE-GAIN-APPREC> 0.18
<PER-SHARE-DIVIDEND> 0.19
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 6.84
<EXPENSE-RATIO> 1.92
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
