N-MFP3 0001107414 XXXXXXXX 2026-06-30 STATE STREET INSTITUTIONAL INVESTMENT TRUST 0001107414 549300P1E098W6ES7M39 State Street Federal Treasury Plus Money Market Fund 984500FCIE7E84F01E90 S000086382 1 N N 333-30810 SSGA Funds Management, Inc. 801-60103 Ernst & Young LLP Boston MA SSGA Funds Management, Inc. SS&C GIDS, Inc. 0000027048 084-00448 Y 0001094885 Treasury Plus Money Market Portfolio S000019934 N N Government N N 1 1 82076879956.08 82356879956.08 0.9814 0.9848 2026-06-01 79157449917.88 79157449917.88 0.9807 0.9807 2026-06-02 75816913937.19 76041913937.19 0.9799 0.9828 2026-06-03 74655455179.87 74880455179.87 0.9796 0.9825 2026-06-04 74907285462.51 75132285462.51 0.9794 0.9824 2026-06-05 73099418994.29 73324418994.29 0.9790 0.9820 2026-06-08 83294195268.20 83294195268.20 0.9841 0.9841 2026-06-09 82327486085.24 82327486085.24 0.9839 0.9839 2026-06-10 76654640874.62 76654640874.62 0.9828 0.9828 2026-06-11 78707966479.14 78707966479.14 0.9830 0.9830 2026-06-12 80712108782.80 80712108782.80 0.9835 0.9835 2026-06-15 81652581897.41 81653581897.41 0.9837 0.9837 2026-06-16 81995039752.48 81996039752.48 0.9813 0.9813 2026-06-17 82318348131.05 82319348131.05 0.9811 0.9811 2026-06-18 82513922008.06 82513922008.06 0.9813 0.9813 2026-06-22 86379225786.15 86379225786.15 0.9821 0.9821 2026-06-23 85352975435.90 85352975435.90 0.9819 0.9819 2026-06-24 87497643890.68 87977643890.68 0.9823 0.9877 2026-06-25 87232751763.65 87432751763.65 0.9821 0.9843 2026-06-26 82920048622.15 83120048622.15 0.9813 0.9836 2026-06-29 85355814807.73 85555814807.73 0.9821 0.9844 2026-06-30 0.00 107900333.72 107900333.72 0.00 489900.12 107410433.60 107410460.0160 Y 1.0000 0.0370 2026-06-01 0.0369 2026-06-02 0.0369 2026-06-03 0.0369 2026-06-04 0.0369 2026-06-05 0.0369 2026-06-08 0.0369 2026-06-09 0.0368 2026-06-10 0.0368 2026-06-11 0.0369 2026-06-12 0.0369 2026-06-15 0.0370 2026-06-16 0.0370 2026-06-17 0.0370 2026-06-18 0.0369 2026-06-22 0.0369 2026-06-23 0.0369 2026-06-24 0.0369 2026-06-25 0.0370 2026-06-26 0.0370 2026-06-29 0.0370 2026-06-30 0.9999 2026-06-01 0.9999 2026-06-02 0.9999 2026-06-03 0.9999 2026-06-04 0.9999 2026-06-05 0.9999 2026-06-08 0.9999 2026-06-09 0.9999 2026-06-10 0.9999 2026-06-11 0.9999 2026-06-12 0.9999 2026-06-15 0.9999 2026-06-16 0.9999 2026-06-17 0.9999 2026-06-18 0.9999 2026-06-22 0.9999 2026-06-23 0.9999 2026-06-24 0.9999 2026-06-25 0.9999 2026-06-26 0.9999 2026-06-29 0.9999 2026-06-30 N N Advantage Class C000251885 1000000.00 107410433.60 107410460.0160 0.9999 2026-06-01 0.9999 2026-06-02 0.9999 2026-06-03 0.9999 2026-06-04 0.9999 2026-06-05 0.9999 2026-06-08 0.9999 2026-06-09 0.9999 2026-06-10 0.9999 2026-06-11 0.9999 2026-06-12 0.9999 2026-06-15 0.9999 2026-06-16 0.9999 2026-06-17 0.9999 2026-06-18 0.9999 2026-06-22 0.9999 2026-06-23 0.9999 2026-06-24 0.9999 2026-06-25 0.9999 2026-06-26 0.9999 2026-06-29 0.9999 2026-06-30 3781276.94 808264.35 2026-06-01 491236.36 391841.96 2026-06-02 125821.40 120673.89 2026-06-03 756818.55 385680.97 2026-06-04 465000.00 1171687.86 2026-06-05 734645.00 554766.79 2026-06-08 1229739.60 449094.40 2026-06-09 2755949.93 411608.78 2026-06-10 82645.62 581511.74 2026-06-11 504596.88 437236.85 2026-06-12 551394.54 485301.55 2026-06-15 248249.36 555563.97 2026-06-16 265381.86 339633.14 2026-06-17 523000.00 127504.33 2026-06-18 146473.00 135470.95 2026-06-22 635700.29 655483.75 2026-06-23 725625.54 196330.78 2026-06-24 739122.18 36477.65 2026-06-25 0.00 883839.15 2026-06-26 361856.72 569125.23 2026-06-29 529000.00 849517.81 2026-06-30 15653533.77 10146615.90 0.0331 2026-06-01 0.0330 2026-06-02 0.0330 2026-06-03 0.0330 2026-06-04 0.0330 2026-06-05 0.0330 2026-06-08 0.0330 2026-06-09 0.0330 2026-06-10 0.0330 2026-06-11 0.0330 2026-06-12 0.0331 2026-06-15 0.0331 2026-06-16 0.0332 2026-06-17 0.0331 2026-06-18 0.0331 2026-06-22 0.0330 2026-06-23 0.0331 2026-06-24 0.0331 2026-06-25 0.0331 2026-06-26 0.0331 2026-06-29 0.0332 2026-06-30 Y 4646.00 Broker-dealer 0.999 0.00 N State Street Treasury Plus Money Market Portfolio State Street Treasury Plus Money Market Portfolio FSSgAK1AW 5493008OWE0VKOXO4934 FSSgAK1AW Investment Company Y 2026-07-01 2026-07-01 2026-07-01 N N N 0.0000 107900333.72 107900333.72 1.0000 N Y Y N STATE STREET INSTITUTIONAL INVESTMENT TRUST 2026-07-08 /s/ Chad Hallett Chad Hallett Deputy Treasurer