N-MFP2 0000798244 XXXXXXXX 2019-11-30 0000798244 CQT3VZHUKW04X1YLM325 S000000762 12 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 N 36 36 48269557.72 30630902.78 45656296.72 44917088.77 48146783.30 181122267.52 173816162.47 156075581.75 172142796.67 161886365.58 0.2329 0.1483 0.2206 0.2052 0.2358 0.8740 0.8418 0.7543 0.7866 0.7927 680.04 204214911.60 204206848.10 16458.70 320569.26 203903417.58 204133424.6280 1.0000 0.0166 0.9990 0.9990 0.9989 0.9989 0.9989 C000002179 1000.00 97259346.96 97369038.9660 0.9990 0.9990 0.9990 0.9989 0.9989 648298.63 791826.28 627606.05 410736.42 1134085.32 1042539.67 430284.30 1066059.01 113646.81 715513.45 2584154.38 3739370.95 0.0094 Y For Class A during the period, MFS waived: $828 management fees; MFD waived: $20,114 12b-1 fees. C000002180 250.00 241209.75 241480.1210 0.9990 0.9990 0.9990 0.9989 0.9989 242.17 0.00 0.00 0.00 0.00 0.00 9.59 12824.50 0.00 0.00 251.76 12824.50 0.0089 Y For Class 529B during the period, MFS waived: $2 management fees; MFD waived: $204 12b-1 fees. C000002181 250.00 6616408.56 6623791.8320 0.9990 0.9990 0.9990 0.9989 0.9989 37020.43 7289.15 31083.14 26332.73 2850.00 63420.03 50382.03 82557.50 55950.00 26492.63 146671.70 198802.89 0.0089 Y For Class 529C during the period, MFS waived: $56 management fees; MFD waived: $5,438 12b-1 fees. C000002182 1000.00 8480149.98 8489678.3830 0.9990 0.9990 0.9990 0.9989 0.9989 15181.63 26632.41 21450.39 11834.30 218551.03 103321.60 91138.65 282837.98 86937.65 107517.58 426442.30 511430.68 0.0094 Y For Class B during the period, MFS waived: $72 management fees; MFD waived: $7,015 12b-1 fees. C000002183 1000.00 16789881.01 16808803.4900 0.9989 0.9989 0.9988 0.9989 0.9989 79228.65 1619544.53 114790.73 767805.97 143093.43 89836.93 42159.23 178671.34 34321.60 126045.91 353367.42 2659032.35 0.0094 Y For Class C during the period, MFS waived: $144 management fees; MFD waived: $13,964 12b-1 fees. C000002184 1.00 7384216.48 7392589.1050 0.9990 0.9990 0.9990 0.9989 0.9989 44494.72 98715.93 108579.85 18462.36 6695.11 12944.62 5353.85 45509.45 8157.96 93539.16 136437.37 263034.76 0.0094 Y For Class R1 during the period, MFS waived: $63 management fees; MFD waived: $6,120 12b-1 fees. C000002186 1.00 28430837.23 28463309.3110 0.9990 0.9990 0.9990 0.9989 0.9989 272326.40 172813.39 41961.94 1560.98 29808.00 57319.94 2051.60 583558.16 19813.52 558788.55 125144.08 1304806.47 0.0094 Y For Class R2 during the period, MFS waived: $247 management fees; MFD waived: $11,991 12b-1 fees. C000002187 1.00 15408364.03 15425622.4590 0.9990 0.9990 0.9989 0.9989 0.9989 18265.10 626624.95 287848.04 939.19 5644.92 5923.07 26227.59 103143.00 20475.46 9140.86 356211.78 717360.63 0.0094 Y For Class R3 during the period, MFS waived: $130 management fees; MFD waived: $3,151 12b-1 fees. C000002188 1.00 2713467.04 2716508.5310 0.9990 0.9990 0.9990 0.9989 0.9989 2947.86 0.00 0.00 0.00 0.00 0.00 130.11 0.00 653.23 642.47 3731.20 642.47 0.0094 Y For Class R4 during the period, MFS waived: $23 management fees. C000002189 250.00 20467287.31 20490227.3800 0.9990 0.9990 0.9990 0.9989 0.9989 64227.88 65795.43 96528.50 115434.10 195382.46 50149.84 423537.91 87307.57 111874.60 110461.61 856175.93 369191.63 0.0089 Y For Class 529A during the period, MFS waived: $170 management fees; MFD waived: $4,136 12b-1 fees. C000206004 1.00 54553.99 54615.1400 0.9990 0.9990 0.9990 0.9989 0.9989 58.92 0.00 0.00 3.79 0.00 0.00 0.00 1.03 0.00 0.00 58.92 4.82 0.0101 Y For Class R6 during the period, MFS waived: $1 management fees. C000206005 1.00 57695.24 57759.9100 0.9990 0.9990 0.9990 0.9989 0.9989 58.87 0.00 41633.80 41633.80 0.00 0.00 0.00 1.09 0.00 0.00 41692.67 41634.89 0.0095 Y For Class I during the period, MFS waived: $1 management fees. Federal Farm Credit Bank Federal Farm Credit Bank 313312QB9 US313312QB90 U.S. Government Agency Debt Y 2019-12-04 2019-12-04 2019-12-04 N N N 0.0160 12008945.76 12008945.76 0.0589 N N Y N Federal Farm Credit Bank Federal Farm Credit Bank 313312QC7 US313312QC73 U.S. Government Agency Debt Y 2019-12-05 2019-12-05 2019-12-05 N N N 0.0160 3999473.32 3999473.32 0.0196 N N Y N Federal Farm Credit Bank Federal Farm Credit Bank 313312SB7 US313312SB72 U.S. Government Agency Debt Y 2020-01-21 2020-01-21 2020-01-21 N N N 0.0162 14757338.80 14757338.80 0.0724 N N Y N Federal Farm Credit Bank Federal Farm Credit Bank 313312SL5 US313312SL54 U.S. Government Agency Debt Y 2020-01-30 2020-01-30 2020-01-30 N N N 0.0162 4358612.52 4358612.52 0.0214 N N N N Federal Farm Credit Bank Federal Farm Credit Bank 313312SM3 US313312SM38 U.S. Government Agency Debt Y 2020-01-31 2020-01-31 2020-01-31 N N N 0.0162 6662298.00 6662298.00 0.0327 N N N N Federal Home Loan Bank Federal Home Loan Bank 313384QR3 2549001DPIFGXC1TOL40 US313384QR38 U.S. Government Agency Debt Y 2019-12-18 2019-12-18 2019-12-18 N N N 0.0160 7894452.46 7894452.46 0.0387 N N Y N Federal Home Loan Bank Federal Home Loan Bank 313384RL5 2549001DPIFGXC1TOL40 US313384RL58 U.S. Government Agency Debt Y 2020-01-06 2020-01-06 2020-01-06 N N N 0.0161 10294062.49 10294062.49 0.0505 N N Y N Federal Home Loan Bank Federal Home Loan Bank 313384RQ4 2549001DPIFGXC1TOL40 US313384RQ46 U.S. Government Agency Debt Y 2020-01-10 2020-01-10 2020-01-10 N N N 0.0161 6204294.66 6204294.66 0.0304 N N Y N Federal Home Loan Bank Federal Home Loan Bank 313384RX9 2549001DPIFGXC1TOL40 US313384RX96 U.S. Government Agency Debt Y 2020-01-17 2020-01-17 2020-01-17 N N N 0.0162 8198309.83 8198309.83 0.0402 N N Y N Federal Home Loan Bank Federal Home Loan Bank 313384SC4 2549001DPIFGXC1TOL40 US313384SC41 U.S. Government Agency Debt Y 2020-01-22 2020-01-22 2020-01-22 N N N 0.0162 8256360.56 8256360.56 0.0405 N N Y N Federal Home Loan Bank Federal Home Loan Bank 313384SZ3 2549001DPIFGXC1TOL40 US313384SZ36 U.S. Government Agency Debt Y 2020-02-12 2020-02-12 2020-02-12 N N N 0.0163 8273440.00 8273440.00 0.0406 N N N N Federal Home Loan Mortgage Corp. Federal Home Loan Mortgage Corp. 313396QA4 S6XOOCT0IEG5ABCC6L87 US313396QA41 U.S. Government Agency Debt Y 2019-12-03 2019-12-03 2019-12-03 N N N 0.0160 4399806.88 4399806.88 0.0216 N N Y N Federal Home Loan Mortgage Corp. Federal Home Loan Mortgage Corp. 313396QB2 S6XOOCT0IEG5ABCC6L87 US313396QB24 U.S. Government Agency Debt Y 2019-12-04 2019-12-04 2019-12-04 N N N 0.0160 2199806.88 2199806.88 0.0108 N N Y N Federal Home Loan Mortgage Corp. Federal Home Loan Mortgage Corp. 313396QC0 S6XOOCT0IEG5ABCC6L87 US313396QC07 U.S. Government Agency Debt Y 2019-12-05 2019-12-05 2019-12-05 N N N 0.0160 10578606.93 10578606.93 0.0519 N N Y N Federal Home Loan Mortgage Corp. Federal Home Loan Mortgage Corp. 313396QD8 S6XOOCT0IEG5ABCC6L87 US313396QD89 U.S. Government Agency Debt Y 2019-12-06 2019-12-06 2019-12-06 N N N 0.0160 5299069.53 5299069.53 0.0260 N N Y N Federal Home Loan Mortgage Corp. Federal Home Loan Mortgage Corp. 313396TH6 S6XOOCT0IEG5ABCC6L87 US313396TH66 U.S. Government Agency Debt Y 2020-02-20 2020-02-20 2020-02-20 N N N 0.0163 10163733.28 10163733.28 0.0498 N N N N Federal National Mortgage Assoc. Federal National Mortgage Assoc. 313588PZ2 B1V7KEBTPIMZEU4LTD58 US313588PZ25 U.S. Government Agency Debt Y 2019-12-02 2019-12-02 2019-12-02 N N N 0.0001 8585000.00 8585000.00 0.0421 N Y Y N Federal National Mortgage Assoc. Federal National Mortgage Assoc. 313588RG2 B1V7KEBTPIMZEU4LTD58 US313588RG26 U.S. Government Agency Debt Y 2020-01-02 2020-01-02 2020-01-02 N N N 0.0161 7381879.10 7381879.10 0.0362 N N Y N Federal National Mortgage Assoc. Federal National Mortgage Assoc. 313588RV9 B1V7KEBTPIMZEU4LTD58 US313588RV92 U.S. Government Agency Debt Y 2020-01-15 2020-01-15 2020-01-15 N N N 0.0162 12271106.76 12271106.76 0.0602 N N Y N Federal National Mortgage Assoc. Federal National Mortgage Assoc. 313588SK2 B1V7KEBTPIMZEU4LTD58 US313588SK29 U.S. Government Agency Debt Y 2020-01-29 2020-01-29 2020-01-29 N N N 0.0162 12861967.27 12861967.27 0.0631 N N N N Goldman Sachs & Co. LLC Goldman Sachs & Co. LLC 1.600000% FOR8UP27PHTHYVLBNG30 0000769993 318991007_1.60_1202 U.S. Treasury Repurchase Agreement, if collateralized only by U.S. Treasuries (including Strips) and cash Y N U.S. Treasury Bill 254900HROIFWPRGM1V77 2042-08-15 2.750000 10655800.00 11841238.52 U.S. Treasuries (including strips) Y 2019-12-02 2019-12-02 2019-12-02 N N N 0.0160 11609000.00 11609000.00 0.0569 N Y Y N JP Morgan Securities LLC JPMorgan Chase 1.630000% ZBUT11V806EZRVTWT807 0001168163 446199002_1.63_1202 U.S. Treasury Repurchase Agreement, if collateralized only by U.S. Treasuries (including Strips) and cash Y N U.S. Treasury Bill 254900HROIFWPRGM1V77 2019-12-05 1.407500 200.00 199.98 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2020-09-30 1.375000 100.00 99.97 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2020-09-10 1.551250 2000.00 1975.04 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2027-07-15 0.375000 400.00 427.75 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2020-09-15 1.375000 100.00 100.05 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2029-02-15 2.625000 400.00 431.90 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2020-02-29 1.375000 20200.00 20251.18 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2022-03-31 1.750000 100.00 100.59 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2023-01-15 0.125000 1600.00 1769.56 U.S. Treasuries (including strips) U.S. Treasury Bill 254900HROIFWPRGM1V77 2022-09-30 1.875000 4397300.00 4442855.02 U.S. Treasuries (including strips) Y 2019-12-02 2019-12-02 2019-12-02 N N N 0.0163 4380000.00 4380000.00 0.0215 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912796TA7 254900HROIFWPRGM1V77 US912796TA76 U.S. Treasury Debt Y 2020-01-09 2020-01-09 2020-01-09 N N N 0.0159 11600784.01 11600784.01 0.0569 N Y Y N U.S. Treasury Bill U.S. Treasury Bill 912796TB5 254900HROIFWPRGM1V77 US912796TB59 U.S. Treasury Debt Y 2020-01-16 2020-01-16 2020-01-16 N N N 0.0159 11976562.56 11976562.56 0.0587 N Y Y N MFS Series Trust I 2019-12-06 /s/Kino Clark Kino Clark Assistant Treasurer