<PAGE> PAGE 1
000 A000000 04/30/98
000 C000000 0000824463
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 3.0.a
000 J000000 A
001 A000000 PUTNAM MASTER INCOME TRUST
001 B000000 811-5375
001 C000000 6172921562
002 A000000 ONE POST OFFICE SQUARE
002 B000000 BOSTON
002 C000000 MA
002 D010000 02109
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 N
007 B000000 0
007 C010100 1
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 A000001 PUTNAM INVESTMENT MANAGEMENT, INC
008 B000001 A
008 C000001 801-7974
008 D010001 BOSTON
008 D020001 MA
008 D030001 02109
013 A000001 COOPERS & LYBRAND L.L.P.
013 B010001 BOSTON
013 B020001 A
013 B030001 02109
015 A000001 PUTNAM FIDUCIARY TRUST CO
015 B000001 C
015 C010001 BOSTON
015 C020001 MA
015 C030001 02109
015 E010001 X
018 000000 Y
019 A000000 Y
019 B000000 99
<PAGE> PAGE 2
019 C000000 PUTNAMFUND
020 A000001 FIMAT FUTURES USA, INC.
020 C000001 9
020 A000002 BANK OF AMERICA
020 B000002 94-1687665
020 C000002 3
020 A000003 MERRILL LYNCH, PIERCE, FENNER, & SMITH, INC.
020 B000003 13-5674085
020 C000003 2
020 A000004 BEAR STERNS & CO.
020 B000004 13-4946705
020 C000004 1
020 C000005 0
020 C000006 0
020 C000007 0
020 C000008 0
020 C000009 0
020 C000010 0
021 000000 15
022 A000001 GOLDMAN SACHS & CO.
022 B000001 13-5108880
022 C000001 1361509
022 D000001 81206
022 A000002 LEHMAN BROTHERS
022 B000002 13-2518466
022 C000002 389113
022 D000002 145986
022 A000003 MERRILL LYNCH, PIERCE, FENNER, & SMITH, INC.
022 B000003 13-5674085
022 C000003 149580
022 D000003 72805
022 A000004 MORGAN (J.P.) SECUTITIES INC.
022 B000004 13-3224016
022 C000004 78957
022 D000004 87819
022 A000005 CREDIT SUISSE FIRST BOSTON
022 C000005 56649
022 D000005 70157
022 A000006 UBS SECURITIES
022 B000006 13-2932996
022 C000006 81945
022 D000006 39292
022 A000007 SALOMON SMITH BARNEY
022 C000007 110791
022 D000007 2559
022 A000008 SALOMON BROTHERS, INC.
022 B000008 13-3082694
022 C000008 56191
022 D000008 36922
022 A000009 BARCLAYS DE ZOETE & WEDD SECURITIES, INC.
022 B000009 13-3297824
<PAGE> PAGE 3
022 C000009 7595
022 D000009 20615
022 A000010 CHASE MANHATTAN BANK
022 C000010 17583
022 D000010 15067
023 C000000 2423192
023 D000000 677869
024 000000 N
025 D000001 0
025 D000002 0
025 D000003 0
025 D000004 0
025 D000005 0
025 D000006 0
025 D000007 0
025 D000008 0
026 A000000 Y
026 B000000 Y
026 C000000 Y
026 D000000 Y
026 E000000 N
026 F000000 N
026 G010000 Y
026 G020000 Y
026 H000000 N
027 000000 N
028 A010000 0
028 A020000 0
028 A030000 0
028 A040000 0
028 B010000 0
028 B020000 0
028 B030000 0
028 B040000 0
028 C010000 0
028 C020000 0
028 C030000 0
028 C040000 0
028 D010000 0
028 D020000 0
028 D030000 0
028 D040000 0
028 E010000 0
028 E020000 0
028 E030000 0
028 E040000 0
028 F010000 0
028 F020000 0
028 F030000 0
028 F040000 0
028 G010000 0
<PAGE> PAGE 4
028 G020000 0
028 G030000 0
028 G040000 0
028 H000000 0
030 A000000 0
030 B000000 0.00
030 C000000 0.00
031 A000000 0
031 B000000 0
032 000000 0
033 000000 0
035 000000 0
036 B000000 0
038 000000 0
042 A000000 0
042 B000000 0
042 C000000 0
042 D000000 0
042 E000000 0
042 F000000 0
042 G000000 0
042 H000000 0
043 000000 0
044 000000 0
045 000000 Y
046 000000 N
047 000000 Y
048 000000 0.000
048 A010000 500000
048 A020000 0.750
048 B010000 500000
048 B020000 0.650
048 C010000 500000
048 C020000 0.600
048 D010000 0
048 D020000 0.000
048 E010000 0
048 E020000 0.000
048 F010000 0
048 F020000 0.000
048 G010000 0
048 G020000 0.000
048 H010000 0
048 H020000 0.000
048 I010000 0
048 I020000 0.000
048 J010000 0
048 J020000 0.000
048 K010000 1500000
048 K020000 0.550
049 000000 N
<PAGE> PAGE 5
050 000000 N
051 000000 N
052 000000 N
053 A000000 N
054 A000000 Y
054 B000000 Y
054 C000000 Y
054 D000000 N
054 E000000 N
054 F000000 N
054 G000000 N
054 H000000 N
054 I000000 N
054 J000000 Y
054 K000000 N
054 L000000 Y
054 M000000 Y
054 N000000 N
054 O000000 Y
055 A000000 N
055 B000000 N
056 000000 N
057 000000 N
058 A000000 N
059 000000 Y
060 A000000 Y
060 B000000 Y
061 000000 1000
062 A000000 Y
062 B000000 0.0
062 C000000 0.0
062 D000000 0.1
062 E000000 0.0
062 F000000 0.0
062 G000000 0.0
062 H000000 0.0
062 I000000 0.0
062 J000000 0.0
062 K000000 0.0
062 L000000 1.0
062 M000000 10.1
062 N000000 18.4
062 O000000 0.0
062 P000000 35.3
062 Q000000 30.6
062 R000000 4.2
063 A000000 0
063 B000000 9.7
064 A000000 N
064 B000000 N
066 A000000 N
<PAGE> PAGE 6
067 000000 N
068 A000000 N
068 B000000 N
069 000000 N
070 A010000 Y
070 A020000 Y
070 B010000 N
070 B020000 N
070 C010000 Y
070 C020000 N
070 D010000 N
070 D020000 N
070 E010000 Y
070 E020000 Y
070 F010000 N
070 F020000 N
070 G010000 Y
070 G020000 Y
070 H010000 N
070 H020000 N
070 I010000 N
070 I020000 N
070 J010000 Y
070 J020000 N
070 K010000 N
070 K020000 N
070 L010000 Y
070 L020000 Y
070 M010000 Y
070 M020000 Y
070 N010000 Y
070 N020000 N
070 O010000 Y
070 O020000 N
070 P010000 Y
070 P020000 N
070 Q010000 N
070 Q020000 N
070 R010000 Y
070 R020000 N
071 A000000 562805
071 B000000 553382
071 C000000 480099
071 D000000 115
072 A000000 6
072 B000000 21803
072 C000000 838
072 D000000 0
072 E000000 0
072 F000000 1794
072 G000000 4
<PAGE> PAGE 7
072 H000000 0
072 I000000 196
072 J000000 112
072 K000000 31
072 L000000 24
072 M000000 11
072 N000000 56
072 O000000 0
072 P000000 0
072 Q000000 0
072 R000000 38
072 S000000 9
072 T000000 0
072 U000000 0
072 V000000 0
072 W000000 11
072 X000000 2286
072 Y000000 0
072 Z000000 20355
072AA000000 0
072BB000000 343
072CC010000 767
072CC020000 0
072DD010000 19432
072DD020000 0
072EE000000 0
073 A010000 0.3660
073 A020000 0.0000
073 B000000 0.0000
073 C000000 0.0000
074 A000000 4185
074 B000000 644
074 C000000 4998
074 D000000 453204
074 E000000 15107
074 F000000 4424
074 G000000 0
074 H000000 0
074 I000000 13512
074 J000000 29649
074 K000000 0
074 L000000 11242
074 M000000 0
074 N000000 536965
074 O000000 22464
074 P000000 989
074 Q000000 0
074 R010000 0
074 R020000 0
074 R030000 0
074 R040000 20514
<PAGE> PAGE 8
074 S000000 0
074 T000000 492998
074 U010000 53096
074 U020000 0
074 V010000 9.29
074 V020000 0.00
074 W000000 0.0000
074 X000000 7448
074 Y000000 0
075 A000000 0
075 B000000 492635
076 000000 8.50
077 A000000 N
078 000000 N
080 A000000 FEDERAL INSURANCE COMPANY
080 B000000 NATIONAL UNION FIRE INSURANCE COMPANY
080 C000000 50000
081 A000000 Y
081 B000000 98
082 A000000 N
082 B000000 0
083 A000000 N
083 B000000 0
084 A000000 N
084 B000000 0
085 A000000 Y
085 B000000 N
086 A010000 0
086 A020000 0
086 B010000 0
086 B020000 0
086 C010000 0
086 C020000 0
086 D010000 0
086 D020000 0
086 E010000 0
086 E020000 0
086 F010000 0
086 F020000 0
087 A010000 SHARES OF BENEFICIAL INTEREST
087 A020000 74683K104
087 A030000 PMT
088 A000000 N
088 B000000 N
088 C000000 N
088 D000000 N
SIGNATURE PAUL BUCUVALAS
TITLE MANAGING DIRECTOR
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Putnam Master Income Trust
</LEGEND>
<SERIES>
<NUMBER> 1
<S> <C>
<PERIOD0-TYPE> SEMI
<FISCAL-YEAR-END> OCT-31-1997
<PERIOD-END> APR-30-1998
<INVESTMENTS-AT-COST> 480,124,057
<INVESTMENTS-AT-VALUE> 491,889,382
<RECEIVABLES> 40,890,004
<ASSETS-OTHER> 4,185,362
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 536,964,748
<PAYABLE-FOR-SECURITIES> 22,463,506
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 21,502,753
<TOTAL-LIABILITIES> 43,966,259
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 484,579,427
<SHARES-COMMON-STOCK> 53,095,749
<SHARES-COMMON-PRIOR> 53,095,749
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> (236,319)
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (2,318,387)
<ACCUM-APPREC-OR-DEPREC> 10,973,768
<NET-ASSETS> 492,998,489
<DIVIDEND-INCOME> 837,636
<INTEREST-INCOME> 21,803,272
<OTHER-INCOME> 0
<EXPENSES-NET> 2,285,510
<NET-INVESTMENT-INCOME> 20,355,398
<REALIZED-GAINS-CURRENT> (343,312)
<APPREC-INCREASE-CURRENT> 767,371
<NET-CHANGE-FROM-OPS> 20,779,457
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (19,432,480)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 0
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 1,346,977
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> (1,159,237)
<OVERDIST-NET-GAINS-PRIOR> (1,975,075)
<GROSS-ADVISORY-FEES> 1,794,288
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 2,348,515
<AVERAGE-NET-ASSETS> 492,634,963
<PER-SHARE-NAV-BEGIN> 9.26
<PER-SHARE-NII> .38
<PER-SHARE-GAIN-APPREC> .02
<PER-SHARE-DIVIDEND> (.37)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.29
<EXPENSE-RATIO> .48
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>