N-MFP2 0000798244 XXXXXXXX 2023-12-31 0000798244 549300QRB5FQ35HH3533 S000000762 9 N N 033-07638 Massachusetts Financial Services Company 801-17352 Deloitte & Touche LLP Boston MA Massachusetts Financial Services Company MFS Service Center, Inc 0000769188 084-01316 N N N Exempt Government Government/Agency N 31 31 292599994.84 313584638.64 339857320.12 311146728.89 327956470.52 470727379.04 470629474.40 446992590.76 453939784.51 449877747.81 0.6214 0.6661 0.7263 0.6653 0.6673 0.9997 0.9997 0.9552 0.9707 0.9153 1.15 463434985.34 463469193.69 28019427.34 2097453.11 489391169.07 489620846.3720 1.0000 0.0536 0.9996 0.9994 0.9994 0.9993 0.9995 C000002179 1000.00 159216756.93 159296857.8720 0.9996 0.9994 0.9994 0.9993 0.9994 1268035.47 1017154.90 679410.37 1982382.14 2503204.43 4362939.01 2660782.74 1852048.06 916891.60 3784965.95 7532618.44 12147566.56 0.0494 Y For Class A during the period, MFS waived: $1,791 management fees; $20,946 expense limitation; MFD waived: $34,379 12b-1 fees. C000002182 1000.00 3044590.64 3046115.8420 0.9996 0.9994 0.9994 0.9993 0.9994 27798.84 10406.79 2400.00 6335.00 0.00 56477.94 143.43 270050.96 10000.00 51925.21 26442.27 386518.48 0.0494 Y For Class B during the period, MFS waived: $36 management fees; $421 expense limitation; MFD waived: $2,760 12b-1 fees. C000002183 1000.00 16223359.55 16231361.2700 0.9996 0.9994 0.9994 0.9993 0.9994 210420.68 198396.98 393542.60 107356.32 197152.63 129737.38 82631.87 408078.94 129842.40 104617.05 869048.70 791787.23 0.0494 Y For Class C during the period, MFS waived: $180 management fees; $2,106 expense limitation; MFD waived: $13,834 12b-1 fees. C000002184 1.00 6793239.71 6796628.9990 0.9996 0.9994 0.9994 0.9993 0.9994 43182.21 12598.31 8473.78 8964.98 9803.95 37968.64 21913.07 28999.31 12937.61 79123.62 81999.38 155056.55 0.0494 Y For Class R1 during the period, MFS waived: $76 management fees; $887 expense limitation; MFD waived: $5,818 12b-1 fees. C000002186 1.00 17184914.94 17193412.5150 0.9996 0.9994 0.9994 0.9993 0.9994 85324.69 29975.07 21269.04 7922.68 59034.00 178076.58 28649.96 135013.41 17592.35 33690.35 201623.92 354703.61 0.0494 Y For Class R2 during the period, MFS waived: $191 management fees; $2,230 expense limitation; MFD waived: $7,326 12b-1 fees. C000002187 1.00 17913322.20 17922132.4510 0.9996 0.9994 0.9994 0.9993 0.9994 190970.83 184746.38 45289.22 8373.23 50788.69 31084.89 15021.26 372546.14 78345.23 965.23 376159.78 523463.98 0.0494 Y For Class R3 during the period, MFS waived: $199 management fees; $2,326 expense limitation; MFD waived: $3,823 12b-1 fees. C000002188 1.00 2821109.92 2822503.5600 0.9996 0.9994 0.9994 0.9993 0.9994 11459.25 0.00 0.00 0.00 0.00 0.00 0.00 17.78 0.00 0.00 11441.47 0.00 0.0494 Y For Class R4 during the period, MFS waived: $31 management fees; $363 expense limitation. C000206004 1.00 249892874.67 250002759.3580 0.9996 0.9994 0.9994 0.9993 0.9995 949258.85 567323.00 79182.88 936512.04 55344.42 1781748.78 225995.34 1192244.27 27868603.78 982320.33 29176835.47 5052840.05 0.0497 Y For Class R6 during the period, MFS waived: $2,476 management fee; $28,138 expense limitation. C000206005 1.00 16301000.51 16309074.5050 0.9996 0.9994 0.9994 0.9993 0.9994 148417.88 9772.45 1304124.69 67196.95 0.00 275316.17 995714.08 86209.56 3053.06 45055.11 2362054.79 475583.01 0.0494 Y For Class I during the period, MFS waived: $174 management fees; $2,031 expense limitation. BOFA Securities Bank of America NA 5.290000% 549300HN4UKV1E2R3U73 0001102113 03199T002_5.29_0102 U.S. Treasury Repurchase Agreement, if collateralized only by U.S. Treasuries (including Strips) and cash Y N U.S. Treasury Bill 254900HROIFWPRGM1V77 2028-04-30 3.500000 47890000.00 47411100.00 U.S. Treasuries (including strips) Y 2024-01-02 2024-01-02 2024-01-02 N N N 0.0529 46481000.00 46481000.00 0.0950 N Y Y N Federal Farm Credit Bank Federal Farm Credit Bank 313312RX0 254900C5LP6DN9OP9V83 US313312RX02 U.S. Government Agency Debt Y 2024-01-17 2024-01-17 2024-01-17 N N N 0.0443 14709441.63 14709441.63 0.0301 N N Y N Federal Farm Credit Bank Federal Farm Credit Bank 313312XU9 254900C5LP6DN9OP9V83 US313312XU98 U.S. Government Agency Debt Y 2024-06-06 2024-06-06 2024-06-06 N N N 0.0512 13587404.43 13587404.43 0.0278 N N N N Federal Home Loan Bank Federal Home Loan Bank 313384RX9 2549001DPIFGXC1TOL40 US313384RX96 U.S. Government Agency Debt Y 2024-01-17 2024-01-17 2024-01-17 N N N 0.0445 18449130.18 18449130.18 0.0377 N N Y N Federal Home Loan Bank Federal Home Loan Bank 313384SC4 2549001DPIFGXC1TOL40 US313384SC41 U.S. Government Agency Debt Y 2024-01-22 2024-01-22 2024-01-22 N N N 0.0463 28401010.10 28401010.10 0.0580 N N Y N Federal Home Loan Mortgage Corp. Federal Home Loan Mortgage Corp. 313396RH8 S6XOOCT0IEG5ABCC6L87 US313396RH84 U.S. Government Agency Debt Y 2024-01-03 2024-01-03 2024-01-03 N N N 0.0210 39471417.41 39471417.41 0.0807 N N Y N Federal National Mortgage Assoc. Federal National Mortgage Assoc. 313588RG2 B1V7KEBTPIMZEU4LTD58 US313588RG26 U.S. Government Agency Debt Y 2024-01-02 2024-01-02 2024-01-02 N N N 0.0000 20987843.31 20987843.31 0.0429 N Y Y N Federal National Mortgage Assoc. Federal National Mortgage Assoc. 313588TH8 B1V7KEBTPIMZEU4LTD58 US313588TH80 U.S. Government Agency Debt Y 2024-02-20 2024-02-20 2024-02-20 N N N 0.0497 20837069.19 20837069.19 0.0426 N N Y N Fixed Income Clearing Corp./State Street Bank & Trust Co. Fixed Income Clearing Corp./State Street Bank & Trust Co. 5.310000% 549300H47WTHXPU08X20 0000093748 85748R009_5.31_0102 U.S. Treasury Repurchase Agreement, if collateralized only by U.S. Treasuries (including Strips) and cash Y N U.S. Treasury Bill 254900HROIFWPRGM1V77 2028-02-15 2.750000 49084200.00 47412602.72 U.S. Treasuries (including strips) Y 2024-01-02 2024-01-02 2024-01-02 N N N 0.0531 46482880.00 46482880.00 0.0950 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912796Z28 254900HROIFWPRGM1V77 US912796Z285 U.S. Treasury Debt Y 2024-02-22 2024-02-22 2024-02-22 N N N 0.0497 23325306.17 23325306.17 0.0477 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912797FS1 254900HROIFWPRGM1V77 US912797FS14 U.S. Treasury Debt Y 2024-06-13 2024-06-13 2024-06-13 N N N 0.0511 17099768.53 17099768.53 0.0349 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912797GE1 254900HROIFWPRGM1V77 US912797GE19 U.S. Treasury Debt Y 2024-02-01 2024-02-01 2024-02-01 N N N 0.0483 42263458.57 42263458.57 0.0864 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912797GN1 254900HROIFWPRGM1V77 US912797GN18 U.S. Treasury Debt Y 2024-02-15 2024-02-15 2024-02-15 N N N 0.0496 23647545.05 23647545.05 0.0483 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912797HX8 254900HROIFWPRGM1V77 US912797HX80 U.S. Treasury Debt Y 2024-01-02 2024-01-02 2024-01-02 N N N 0.0000 25000000.00 25000000.00 0.0511 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912797HZ3 254900HROIFWPRGM1V77 US912797HZ39 U.S. Treasury Debt Y 2024-01-16 2024-01-16 2024-01-16 N N N 0.0441 39818421.26 39818421.26 0.0814 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912797JA6 254900HROIFWPRGM1V77 US912797JA69 U.S. Treasury Debt Y 2024-01-23 2024-01-23 2024-01-23 N N N 0.0467 29608726.26 29608726.26 0.0605 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912797JH1 254900HROIFWPRGM1V77 US912797JH13 U.S. Treasury Debt Y 2024-03-12 2024-03-12 2024-03-12 N N N 0.0505 13264563.25 13264563.25 0.0271 N Y Y N MFS Series Trust I 2024-01-08 Kino Clark Kino Clark Assistant Treasurer