<PAGE> PAGE 1
000 A000000 06/30/95
000 C000000 0000082345
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000 F000000 Y
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001 A000000 MASTER RESERVES TRUST
001 B000000 811-2597
001 C000000 6173383200
002 A000000 200 BERKELEY STREET
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002 C000000 MA
002 D010000 02116
003 000000 N
004 000000 N
005 000000 N
006 000000 N
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007 C010100 1
007 C020100 MONEY MARKET PORTFOLIOS
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007 C010200 2
007 C010300 3
007 C010400 4
007 C010500 5
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
008 A00AA01 KEYSTONE INVESWTMENT MANAGEMENT CO.
008 B00AA01 A
008 C00AA01 801-8327
008 D01AA01 BOSTON
008 D02AA01 MA
008 D03AA01 02110
010 A00AA01 KEYSTONE INVESTMENT, INC.
010 C01AA01 BOSTON
010 C02AA01 MA
010 C03AA01 02116
010 C04AA01 5034
011 A00AA01 KEYSTONE INVESTMENT DISTRIBUTORS, CO
011 B00AA01 8-2597
011 C01AA01 BOSTON
011 C02AA01 MA
011 C03AA01 02116
011 C04AA01 5034
<PAGE> PAGE 2
077 A000000 Y
077 B000000 N
077 C000000 N
077 D000000 N
077 E000000 N
077 F000000 N
077 G000000 N
077 H000000 N
077 I000000 N
077 J000000 N
077 K000000 N
077 L000000 N
077 M000000 N
077 N000000 N
077 O000000 N
077 P000000 N
077 Q010000 Y
077 Q020000 N
077 Q030000 N
078 000000 N
062 A000100 Y
062 B000100 3.8
062 C000100 35.0
062 D000100 34.3
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062 F000100 0.0
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<PAGE> PAGE 3
072 H000100 0
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<PAGE> PAGE 4
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<PAGE> PAGE 5
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<PAGE> PAGE 6
062 L000500 1.5
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072 A000500 7
074 N000500 114394
074 T000500 113932
075 A000500 134008
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062 A000600 Y
062 B000600 0.0
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SIGNATURE KEVIN J. MORRISSEY
TITLE TREASURER
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM ACCOUNTING
RECORDS AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH ACCOUNTING
RECORDS.
</LEGEND>
<SERIES>
<NUMBER> 101
<NAME> MASTER RESERVES TRUST CLASS A
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1994
<PERIOD-START> JAN-01-1995
<PERIOD-END> JUN-30-1995
<INVESTMENTS-AT-COST> 25,718,505
<INVESTMENTS-AT-VALUE> 25,718,505
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<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 25,725,748
<PAYABLE-FOR-SECURITIES> 128,258
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 13,835
<TOTAL-LIABILITIES> 142,093
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 25,578,677
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<SHARES-COMMON-PRIOR> 30,314,179
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> (3,902)
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<OVERDISTRIBUTION-GAINS> 0
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<NET-ASSETS> 25,583,655
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 585,244
<OTHER-INCOME> 0
<EXPENSES-NET> (8,848)
<NET-INVESTMENT-INCOME> 576,396
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 12
<NET-CHANGE-FROM-OPS> 576,408
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (576,396)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 57,116,190
<NUMBER-OF-SHARES-REDEEMED> (62,455,208)
<SHARES-REINVESTED> 608,482
<NET-CHANGE-IN-ASSETS> (4,730,524)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 8,880
<OVERDISTRIB-NII-PRIOR> (3,902)
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (8,848)
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> (8,848)
<AVERAGE-NET-ASSETS> 19,828,536
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.03
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.03)
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.09
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
