PAGE 1 000 A000000 04/30/2009 000 C000000 0001275214 000 D000000 N 000 E000000 NF 000 F000000 Y 000 G000000 N 000 H000000 N 000 I000000 6.1 000 J000000 A 001 A000000 CALAMOS STRATEGIC TOTAL RETURN FUND 001 B000000 811-21484 001 C000000 6302457200 002 A000000 2020 CALAMOS COURT 002 B000000 NAPERVILLE 002 C000000 IL 002 D010000 60563 003 000000 N 004 000000 N 005 000000 N 006 000000 N 007 A000000 N 007 B000000 1 007 C010100 1 008 A000001 CALAMOS ADVISORS LLC 008 B000001 A 008 C000001 801-29688 008 D010001 NAPERVILLE 008 D020001 IL 008 D030001 60563 010 A000001 State Street Bank and Trust Company 010 B000001 028-00733 010 C010001 Boston 010 C020001 MA 010 C030001 02111 012 A000001 BANK OF NEW YORK (COMMON) 012 B000001 85-05006 012 C010001 NEW YORK 012 C020001 NY 012 C030001 10286 012 A000002 BANK OF NEW YORK (PREFERRED) 012 B000002 85-05006 012 C010002 NEW YORK 012 C020002 NY 012 C030002 10286 013 A000001 Deloitte & Touche LLP 013 B010001 Chicago 013 B020001 IL 013 B030001 60606 014 A000001 CALAMOS FINANCIAL SERVICES, INC. 014 B000001 8-37854 015 A000001 BANK OF NEW YORK PAGE 2 015 B000001 C 015 C010001 NEW YORK 015 C020001 NY 015 C030001 10286 015 E010001 X 015 A000002 EUROCLEAR BANK 015 B000002 S 015 C010002 BRUSSELS 015 D010002 BELGIUM 015 E040002 X 015 A000003 BNP Paribas Security Services 015 B000003 S 015 C010003 Paris 015 D010003 France 015 E040003 X 018 000000 Y 019 A000000 Y 019 B000000 21 019 C000000 CALAMOSINV 020 A000001 SUSQUEHANNA INVESTMENT GROUP 020 B000001 23-2454154 020 C000001 457 020 A000002 GOLDMAN, SACHS & CO. 020 B000002 13-5108880 020 C000002 51 020 A000003 CREDIT SUISSE 020 B000003 13-2853402 020 C000003 24 020 A000004 BANK OF AMERICA SECURITIES LLC 020 B000004 56-2058405 020 C000004 19 020 A000005 BARCLAYS GLOBAL INVESTORS SERVICES 020 B000005 94-3231066 020 C000005 15 020 A000006 JEFFERIES & CO. INC. 020 B000006 95-2622900 020 C000006 12 020 A000007 DEUTSCHE BANK SECURITIES, INC. 020 B000007 13-2730828 020 C000007 11 020 A000008 ITG, INC. 020 B000008 95-4339369 020 C000008 10 020 A000009 J.P. MORGAN SECURITIES INC. 020 B000009 13-3224016 020 C000009 8 020 A000010 ARCHIPELAGO SECURITIES LLC 020 B000010 22-3685626 020 C000010 1 021 000000 613 PAGE 3 022 A000003 SUSQUEHANNA INVESTMENT GROUP 022 B000003 23-2454154 022 C000003 13329 022 D000003 54402 022 A000004 CREDIT SUISSE 022 B000004 13-2853402 022 C000004 47603 022 D000004 10281 022 A000005 ITG, INC. 022 B000005 95-4339369 022 C000005 0 022 D000005 45876 022 A000006 CITIGROUP GLOBAL MARKETS, INC. 022 B000006 11-2418191 022 C000006 0 022 D000006 30023 022 A000007 J.P. MORGAN SECURITIES INC. 022 B000007 13-3224016 022 C000007 4723 022 D000007 22679 022 A000008 GOLDMAN, SACHS & CO. 022 B000008 13-5108880 022 C000008 6644 022 D000008 18976 022 A000009 BANK OF AMERICA SECURITIES LLC 022 B000009 56-2058405 022 C000009 186 022 D000009 17628 022 A000010 BARCLAYS GLOBAL INVESTORS SERVICES 022 B000010 94-3231066 022 C000010 273 022 D000010 13439 022 A000011 BROADPOINT SECURITIES GROUP, INC. 022 B000011 22-2655804 022 C000011 0 022 D000011 12399 022 A000012 ARCHIPELAGO SECURITIES LLC 022 B000012 22-3685626 022 C000012 186 022 D000012 8540 023 C000000 260737 023 D000000 440187 024 000000 Y 025 A000001 J.P. MORGAN SECURITIES INC. 025 B000001 13-3224016 025 C000001 E 025 D000001 34650 025 A000002 CITIGROUP GLOBAL MARKETS, INC. 025 B000002 11-2418191 025 C000002 E 025 D000002 21330 025 A000003 BANK OF AMERICA SECURITIES LLC PAGE 4 025 B000003 56-2058405 025 C000003 E 025 D000003 29620 026 A000000 N 026 B000000 Y 026 C000000 N 026 D000000 Y 026 E000000 N 026 F000000 N 026 G010000 N 026 G020000 N 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 0 028 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 PAGE 5 038 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 1.000 048 A010000 0 048 A020000 0.000 048 B010000 0 048 B020000 0.000 048 C010000 0 048 C020000 0.000 048 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 0 048 K020000 0.000 049 000000 N 050 000000 N 051 000000 N 052 000000 N 053 A000000 Y 053 B000000 N 053 C000000 N 054 A000000 Y 054 B000000 Y 054 C000000 N 054 D000000 N 054 E000000 N 054 F000000 N 054 G000000 N PAGE 6 054 H000000 Y 054 I000000 N 054 J000000 Y 054 K000000 N 054 L000000 N 054 M000000 Y 054 N000000 N 054 O000000 N 055 A000000 N 055 B000000 Y 056 000000 Y 057 000000 N 058 A000000 N 059 000000 Y 060 A000000 Y 060 B000000 Y 061 000000 0 062 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 N 066 E000000 N 066 F000000 N 066 G000000 Y 067 000000 N 068 A000000 N 068 B000000 N 069 000000 N 070 A010000 Y 070 A020000 N 070 B010000 Y PAGE 7 070 B020000 Y 070 C010000 Y 070 C020000 N 070 D010000 Y 070 D020000 Y 070 E010000 Y 070 E020000 N 070 F010000 Y 070 F020000 N 070 G010000 Y 070 G020000 N 070 H010000 Y 070 H020000 N 070 I010000 Y 070 I020000 N 070 J010000 Y 070 J020000 Y 070 K010000 Y 070 K020000 Y 070 L010000 Y 070 L020000 Y 070 M010000 Y 070 M020000 Y 070 N010000 Y 070 N020000 Y 070 O010000 Y 070 O020000 Y 070 P010000 Y 070 P020000 Y 070 Q010000 N 070 Q020000 N 070 R010000 Y 070 R020000 N 071 A000000 74476 071 B000000 199692 071 C000000 1646149 071 D000000 5 072 A000000 6 072 B000000 30420 072 C000000 29578 072 D000000 0 072 E000000 6 072 F000000 8151 072 G000000 0 072 H000000 0 072 I000000 15 072 J000000 26 072 K000000 0 072 L000000 190 072 M000000 56 072 N000000 67 PAGE 8 072 O000000 0 072 P000000 7482 072 Q000000 153 072 R000000 61 072 S000000 85 072 T000000 0 072 U000000 0 072 V000000 0 072 W000000 1668 072 X000000 17954 072 Y000000 15 072 Z000000 42065 072AA000000 104492 072BB000000 206022 072CC010000 84179 072CC020000 0 072DD010000 70464 072DD020000 0 072EE000000 0 073 A010000 0.4500 073 A020000 0.0000 073 B000000 0.0000 073 C000000 0.0000 074 A000000 29 074 B000000 0 074 C000000 2357 074 D000000 709514 074 E000000 175914 074 F000000 797473 074 G000000 2053 074 H000000 0 074 I000000 17204 074 J000000 0 074 K000000 0 074 L000000 21947 074 M000000 351 074 N000000 1726842 074 O000000 0 074 P000000 1457 074 Q000000 299000 074 R010000 0 074 R020000 0 074 R030000 46275 074 R040000 2399 074 S000000 200018 074 T000000 1177693 074 U010000 154514 074 U020000 0 074 V010000 7.62 074 V020000 0.00 074 W000000 0.0000 PAGE 9 074 X000000 120 074 Y000000 846554 075 A000000 0 075 B000000 1091411 076 000000 6.55 077 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 080 C000000 0 081 B000000 0 082 B000000 0 083 B000000 0 084 B000000 0 086 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 COMMON STOCK 087 A020000 128125101 087 A030000 CSQ 088 A000000 N 088 B000000 N 088 C000000 Y 088 D000000 Y SIGNATURE NIMISH S. BHATT TITLE TREASURER