<PAGE> PAGE 1
000 A000000 01/31/97
000 C000000 0000081269
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 INVESTORS FUND
001 B000000 811-159
001 C000000 6172921000
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
011 A000001 PUTNAM MUTUAL FUNDS
011 B000001 8-5088
011 C010001 BOSTON
011 C020001 MA
011 C030001 02109
012 A000001 PUTNAM INVESTOR SERVICES
012 B000001 84-401299
012 C010001 BOSTON
012 C020001 MA
012 C030001 02109
013 A000001 COOPERS & LYBRAND L.L.P.
013 B010001 BOSTON
013 B020001 MA
<PAGE> PAGE 2
013 B030001 02109
015 A000001 PUTNAM FIDUCIARY TRUST COMPANY
015 B000001 C
015 C010001 BOSTON
015 C020001 MA
015 C030001 02109
015 E010001 X
018 000000 Y
019 A000000 Y
019 B000000 98
019 C000000 PUTNAMFUND
020 A000001 SALOMON BROTHERS INC.
020 B000001 13-3082694
020 C000001 154
020 A000002 FIRST BOSTON CO.
020 B000002 13-5659485
020 C000002 152
020 A000003 PAINE WEBBER INC.
020 B000003 13-2638166
020 C000003 126
020 A000004 MERRILL LYNCH, PIERCE, FENNER & SMITH, INC.
020 B000004 13-5674085
020 C000004 90
020 A000005 EDWARDS (A.G.) & SONS INC.
020 B000005 43-0895477
020 C000005 79
020 A000006 LEHMAN BROTHERS
020 B000006 13-2518466
020 C000006 68
020 A000007 SMITH, BARNEY, HARRIS, UPHAM, & CO.
020 B000007 13-1912900
020 C000007 64
020 A000008 BRIDGE TRADING CO.
020 B000008 43-1034850
020 C000008 54
020 A000009 CHEMICAL BANK (SECURITIES)
020 B000009 13-4994650
020 C000009 41
020 A000010 FIRST UNION SECURITIES
020 C000010 35
021 000000 1329
022 A000001 LEHMAN BROTHERS
022 B000001 13-2518466
022 C000001 4501910
022 D000001 16490
022 A000002 MORGAN(J.P.) SECURITIES INC.
022 B000002 13-3224016
022 C000002 177809
022 D000002 0
022 A000003 GOLDMAN SACHS & CO.
022 B000003 13-5108880
<PAGE> PAGE 3
022 C000003 27639
022 D000003 32546
022 A000004 SBC WARBURG
022 C000004 59000
022 D000004 0
022 A000005 UBS SECURITIES
022 B000005 13-2932996
022 C000005 58054
022 D000005 0
022 A000006 MORGAN STANLEY
022 B000006 13-2655998
022 C000006 23388
022 D000006 22377
022 A000007 SMITH, BARNEY, HARRIS UPHAM & CO.
022 B000007 13-1912900
022 C000007 20909
022 D000007 11992
022 A000008 FIRST BOSTON CO.
022 B000008 13-5659485
022 C000008 30460
022 D000008 946
022 A000009 WESSELES, ARNOLD & HENDERSON
022 B000009 41-1554568
022 C000009 11632
022 D000009 13341
022 A000010 SALOMON BROTHERS INC.
022 B000010 13-3082694
022 C000010 0
022 D000010 22590
023 C000000 4938502
023 D000000 132158
024 000000 N
025 A000001 DELETE
025 D000001 0
025 A000002 DELETE
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
<PAGE> PAGE 4
027 000000 Y
028 A010000 32414
028 A020000 0
028 A030000 0
028 A040000 21829
028 B010000 33704
028 B020000 0
028 B030000 0
028 B040000 17284
028 C010000 76177
028 C020000 0
028 C030000 0
028 C040000 34369
028 D010000 70605
028 D020000 0
028 D030000 0
028 D040000 34543
028 E010000 60767
028 E020000 156266
028 E030000 0
028 E040000 49891
028 F010000 87230
028 F020000 -4837
028 F030000 0
028 F040000 42790
028 G010000 360897
028 G020000 151429
028 G030000 0
028 G040000 200706
028 H000000 360897
029 000000 Y
030 A000000 205
030 B000000 5.75
030 C000000 3.50
031 A000000 205
031 B000000 0
032 000000 0
033 000000 0
034 000000 Y
035 000000 81
036 A000000 N
036 B000000 0
037 000000 N
038 000000 0
039 000000 N
040 000000 Y
041 000000 Y
042 A000000 0
042 B000000 0
042 C000000 100
042 D000000 0
<PAGE> PAGE 5
042 E000000 0
042 F000000 0
042 G000000 0
042 H000000 0
043 000000 2284
044 000000 0
045 000000 Y
046 000000 N
047 000000 Y
048 000000 0.000
048 A010000 500000
048 A020000 0.650
048 B010000 500000
048 B020000 0.550
048 C010000 500000
048 C020000 0.500
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 0.450
049 000000 N
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
<PAGE> PAGE 6
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 500
062 A000000 N
062 B000000 0.0
062 C000000 0.0
062 D000000 0.0
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 0.0
062 M000000 0.0
062 N000000 0.0
062 O000000 0.0
062 P000000 0.0
062 Q000000 0.0
062 R000000 0.0
063 A000000 0
063 B000000 0.0
066 A000000 Y
066 B000000 N
066 C000000 N
066 D000000 Y
066 E000000 N
066 F000000 N
066 G000000 N
067 000000 N
068 A000000 N
068 B000000 N
069 000000 N
070 A010000 Y
070 A020000 Y
070 B010000 Y
070 B020000 N
070 C010000 N
070 C020000 N
070 D010000 Y
070 D020000 N
070 E010000 N
070 E020000 N
<PAGE> PAGE 7
070 F010000 Y
070 F020000 N
070 G010000 N
070 G020000 N
070 H010000 Y
070 H020000 N
070 I010000 N
070 I020000 N
070 J010000 Y
070 J020000 N
070 K010000 N
070 K020000 Y
070 L010000 Y
070 L020000 Y
070 M010000 Y
070 M020000 N
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 847055
071 B000000 711156
071 C000000 1342354
071 D000000 53
072 A000000 6
072 B000000 1840
072 C000000 8778
072 D000000 0
072 E000000 0
072 F000000 4074
072 G000000 11
072 H000000 0
072 I000000 913
072 J000000 39
072 K000000 146
072 L000000 69
072 M000000 20
072 N000000 21
072 O000000 0
072 P000000 0
072 Q000000 0
072 R000000 27
072 S000000 10
072 T000000 2284
072 U000000 0
<PAGE> PAGE 8
072 V000000 0
072 W000000 12
072 X000000 7626
072 Y000000 0
072 Z000000 2992
072AA000000 109934
072BB000000 0
072CC010000 171132
072CC020000 0
072DD010000 6836
072DD020000 187
072EE000000 148105
073 A010000 0.0500
073 A020000 0.0100
073 B000000 1.1700
073 C000000 0.0000
074 A000000 36
074 B000000 58063
074 C000000 0
074 D000000 0
074 E000000 0
074 F000000 1574903
074 G000000 0
074 H000000 0
074 I000000 0
074 J000000 21752
074 K000000 9084
074 L000000 1074
074 M000000 0
074 N000000 1664912
074 O000000 38049
074 P000000 2945
074 Q000000 0
074 R010000 0
074 R020000 0
074 R030000 0
074 R040000 1592
074 S000000 0
074 T000000 1622326
074 U010000 145836
074 U020000 18745
074 V010000 9.81
074 V020000 9.55
074 W000000 0.0000
074 X000000 53110
074 Y000000 0
075 A000000 0
075 B000000 1415323
076 000000 0.00
077 A000000 N
078 000000 N
<PAGE> PAGE 9
080 A000000 FEDERAL INSURANCE COMPANU
080 B000000 NATIONAL UNION FIRE INSURANCE COMPANY
080 C000000 50000
081 A000000 Y
081 B000000 97
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
SIGNATURE PAUL G. BUCUVALAS
TITLE VICE PRESIDENT
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Financial Data Schedule for Putnam Investors Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> CLASS A
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> JUL-31-1996
<PERIOD-END> JAN-31-1997
<INVESTMENTS-AT-COST> 1,301,344,072
<INVESTMENTS-AT-VALUE> 1,632,966,351
<RECEIVABLES> 31,909,037
<ASSETS-OTHER> 36,254
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 11,664,911,642
<PAYABLE-FOR-SECURITIES> 38,048,552
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 4,536,911
<TOTAL-LIABILITIES> 42,585,463
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,230,827,099
<SHARES-COMMON-STOCK> 145,835,978
<SHARES-COMMON-PRIOR> 121,759,351
<ACCUMULATED-NII-CURRENT> 2,512,907
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 57,363,894
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 331,622,279
<NET-ASSETS> 1,622,326,179
<DIVIDEND-INCOME> 8,778,002
<INTEREST-INCOME> 1,840,733
<OTHER-INCOME> 0
<EXPENSES-NET> 7,626,308
<NET-INVESTMENT-INCOME> 2,992,427
<REALIZED-GAINS-CURRENT> 109,934,329
<APPREC-INCREASE-CURRENT> 171,132,130
<NET-CHANGE-FROM-OPS> 284,058,886
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (6,835,610)
<DISTRIBUTIONS-OF-GAINS> (148,104,876)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 24,891,805
<NUMBER-OF-SHARES-REDEEMED> (15,648,371)
<SHARES-REINVESTED> 14,833,193
<NET-CHANGE-IN-ASSETS> 423,034,117
<ACCUMULATED-NII-PRIOR> 6,575,540
<ACCUMULATED-GAINS-PRIOR> 113,496,233
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4,073,833
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 7,749,159
<AVERAGE-NET-ASSETS> 1,278,821,989
<PER-SHARE-NAV-BEGIN> 9.07
<PER-SHARE-NII> .02
<PER-SHARE-GAIN-APPREC> 1.94
<PER-SHARE-DIVIDEND> (.05)
<PER-SHARE-DISTRIBUTIONS> (1.17)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.81
<EXPENSE-RATIO> .51
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Financial Data Schedule for Putnam Investors Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> CLASS B
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> JUL-31-1996
<PERIOD-END> JAN-31-1997
<INVESTMENTS-AT-COST> 1,301,344,072
<INVESTMENTS-AT-VALUE> 1,632,966,351
<RECEIVABLES> 31,909,037
<ASSETS-OTHER> 36,254
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 11,664,911,642
<PAYABLE-FOR-SECURITIES> 38,048,552
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 4,536,911
<TOTAL-LIABILITIES> 42,585,463
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,230,827,099
<SHARES-COMMON-STOCK> 18,744,725
<SHARES-COMMON-PRIOR> 10,094,696
<ACCUMULATED-NII-CURRENT> 2,512,907
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 57,363,894
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 331,622,279
<NET-ASSETS> 1,622,326,179
<DIVIDEND-INCOME> 8,778,002
<INTEREST-INCOME> 1,840,733
<OTHER-INCOME> 0
<EXPENSES-NET> 7,626,308
<NET-INVESTMENT-INCOME> 2,992,427
<REALIZED-GAINS-CURRENT> 109,934,329
<APPREC-INCREASE-CURRENT> 171,132,130
<NET-CHANGE-FROM-OPS> 284,058,886
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (187,272)
<DISTRIBUTIONS-OF-GAINS> (16,854,480)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 11,397,288
<NUMBER-OF-SHARES-REDEEMED> (4,533,434)
<SHARES-REINVESTED> 1,786,175
<NET-CHANGE-IN-ASSETS> 423,034,117
<ACCUMULATED-NII-PRIOR> 6,575,540
<ACCUMULATED-GAINS-PRIOR> 113,496,233
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4,073,833
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 7,749,159
<AVERAGE-NET-ASSETS> 128,351,672
<PER-SHARE-NAV-BEGIN> 8.85
<PER-SHARE-NII> .01
<PER-SHARE-GAIN-APPREC> 1.89
<PER-SHARE-DIVIDEND> (.01)
<PER-SHARE-DISTRIBUTIONS> (1.17)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.55
<EXPENSE-RATIO> .89
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Financial Data Schedule for Putnam Investors Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> CLASS M
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> JUL-31-1996
<PERIOD-END> JAN-31-1997
<INVESTMENTS-AT-COST> 1,301,344,072
<INVESTMENTS-AT-VALUE> 1,632,966,351
<RECEIVABLES> 31,909,037
<ASSETS-OTHER> 36,254
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 11,664,911,642
<PAYABLE-FOR-SECURITIES> 38,048,552
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 4,536,911
<TOTAL-LIABILITIES> 42,585,463
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,230,827,099
<SHARES-COMMON-STOCK> 1,266,128
<SHARES-COMMON-PRIOR> 627,491
<ACCUMULATED-NII-CURRENT> 2,512,907
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 57,363,894
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 331,622,279
<NET-ASSETS> 1,622,326,179
<DIVIDEND-INCOME> 8,778,002
<INTEREST-INCOME> 1,840,733
<OTHER-INCOME> 0
<EXPENSES-NET> 7,626,308
<NET-INVESTMENT-INCOME> 2,992,427
<REALIZED-GAINS-CURRENT> 109,934,329
<APPREC-INCREASE-CURRENT> 171,132,130
<NET-CHANGE-FROM-OPS> 284,058,886
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (32,178)
<DISTRIBUTIONS-OF-GAINS> (1,107,312)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 729,271
<NUMBER-OF-SHARES-REDEEMED> (213,199)
<SHARES-REINVESTED> 122,565
<NET-CHANGE-IN-ASSETS> 423,034,117
<ACCUMULATED-NII-PRIOR> 6,575,540
<ACCUMULATED-GAINS-PRIOR> 113,496,233
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4,073,833
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 7,749,159
<AVERAGE-NET-ASSETS> 8,141,291
<PER-SHARE-NAV-BEGIN> 9.00
<PER-SHARE-NII> .01
<PER-SHARE-GAIN-APPREC> 1.93
<PER-SHARE-DIVIDEND> (.03)
<PER-SHARE-DISTRIBUTIONS> (1.17)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.73
<EXPENSE-RATIO> .76
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Financial Data Schedule for Putnam Investors Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> CLASS Y
<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> JUL-31-1996
<PERIOD-END> JAN-31-1997
<INVESTMENTS-AT-COST> 1,301,344,072
<INVESTMENTS-AT-VALUE> 1,632,966,351
<RECEIVABLES> 31,909,037
<ASSETS-OTHER> 36,254
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 11,664,911,642
<PAYABLE-FOR-SECURITIES> 38,048,552
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 4,536,911
<TOTAL-LIABILITIES> 42,585,463
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,230,827,099
<SHARES-COMMON-STOCK> 10,560
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 2,512,907
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 57,363,894
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 331,622,279
<NET-ASSETS> 1,622,326,179
<DIVIDEND-INCOME> 8,778,002
<INTEREST-INCOME> 1,840,733
<OTHER-INCOME> 0
<EXPENSES-NET> 7,626,308
<NET-INVESTMENT-INCOME> 2,992,427
<REALIZED-GAINS-CURRENT> 109,934,329
<APPREC-INCREASE-CURRENT> 171,132,130
<NET-CHANGE-FROM-OPS> 284,058,886
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 10,622
<NUMBER-OF-SHARES-REDEEMED> (62)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 423,034,117
<ACCUMULATED-NII-PRIOR> 6,575,540
<ACCUMULATED-GAINS-PRIOR> 113,496,233
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4,073,833
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 7,749,159
<AVERAGE-NET-ASSETS> 51,882
<PER-SHARE-NAV-BEGIN> 9.26
<PER-SHARE-NII> .02
<PER-SHARE-GAIN-APPREC> .53
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 9.81
<EXPENSE-RATIO> .05
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
