N-MFP3 0001060517 XXXXXXXX 2026-07-31 UBS Series Funds 0001060517 54930058UKPXVB81RJ71 UBS Select Treasury Preferred Fund 549300DXQ8KM8WHPPG39 S000018677 1 N N 333-52965 UBS ASSET MANAGEMENT (AMERICAS) LLC 801-34910 Ernst & Young LLP New York NY UBS ASSET MANAGEMENT (AMERICAS) LLC BNY Mellon Investment Servicing (US) Inc. 0000849542 084-01761 Y 0001403166 Treasury Master Fund S000019503 N N Government N Y 1 1 43885734887.99 43885734887.99 0.9993 0.9993 2026-07-01 42201202439.28 42201202439.28 0.9991 0.9991 2026-07-02 42734372978.28 42734372978.28 0.9993 0.9993 2026-07-06 42835687252.23 42835687252.23 0.9992 0.9992 2026-07-07 43272000719.60 43272000719.60 0.9993 0.9993 2026-07-08 43313900645.54 43313900645.54 0.9992 0.9992 2026-07-09 43605064720.33 43605064720.33 0.9991 0.9991 2026-07-10 43461586898.74 43461586898.74 0.9992 0.9992 2026-07-13 42840144144.90 42840144144.90 0.9992 0.9992 2026-07-14 43121475222.46 43121475222.46 0.9992 0.9992 2026-07-15 42095850041.70 42095850041.70 0.9991 0.9991 2026-07-16 42019546548.29 42019546548.29 0.9990 0.9990 2026-07-17 44003258507.89 44003258507.89 0.9991 0.9991 2026-07-20 42628762576.25 42628762576.25 0.9991 0.9991 2026-07-21 43060494076.97 43060494076.97 0.9991 0.9991 2026-07-22 41449436294.82 41449436294.82 0.9990 0.9990 2026-07-23 41783568407.41 41783568407.41 0.9989 0.9989 2026-07-24 41612098135.94 41612098135.94 0.9990 0.9990 2026-07-27 41272129589.50 41272129589.50 0.9990 0.9990 2026-07-28 42380091980.61 42380091980.61 0.9990 0.9990 2026-07-29 41716870183.95 41716870183.95 0.9990 0.9990 2026-07-30 42603744067.91 42603744067.91 0.9998 0.9998 2026-07-31 0.00 24436556417.04 0.00 0.00 77310216.33 24359246200.71 24358453948.5300 Y 1.0000 0.0371 2026-07-01 0.0371 2026-07-02 0.0371 2026-07-06 0.0371 2026-07-07 0.0371 2026-07-08 0.0370 2026-07-09 0.0369 2026-07-10 0.0369 2026-07-13 0.0369 2026-07-14 0.0369 2026-07-15 0.0370 2026-07-16 0.0371 2026-07-17 0.0371 2026-07-20 0.0371 2026-07-21 0.0371 2026-07-22 0.0371 2026-07-23 0.0372 2026-07-24 0.0372 2026-07-27 0.0373 2026-07-28 0.0373 2026-07-29 0.0374 2026-07-30 0.0374 2026-07-31 1.0000 2026-07-01 1.0001 2026-07-02 1.0000 2026-07-06 1.0000 2026-07-07 1.0000 2026-07-08 1.0001 2026-07-09 1.0000 2026-07-10 1.0000 2026-07-13 1.0001 2026-07-14 1.0001 2026-07-15 1.0001 2026-07-16 1.0000 2026-07-17 1.0000 2026-07-20 1.0000 2026-07-21 1.0000 2026-07-22 1.0000 2026-07-23 1.0000 2026-07-24 1.0000 2026-07-27 1.0000 2026-07-28 1.0001 2026-07-29 1.0001 2026-07-30 1.0001 2026-07-31 N N Single Class C000051800 50000000.00 24359246200.71 24358453948.5300 1.0000 2026-07-01 1.0001 2026-07-02 1.0000 2026-07-06 1.0000 2026-07-07 1.0000 2026-07-08 1.0001 2026-07-09 1.0000 2026-07-10 1.0000 2026-07-13 1.0001 2026-07-14 1.0001 2026-07-15 1.0001 2026-07-16 1.0000 2026-07-17 1.0000 2026-07-20 1.0000 2026-07-21 1.0000 2026-07-22 1.0000 2026-07-23 1.0000 2026-07-24 1.0000 2026-07-27 1.0000 2026-07-28 1.0001 2026-07-29 1.0001 2026-07-30 1.0001 2026-07-31 2083909081.80 585899191.20 2026-07-01 190665705.17 950764312.40 2026-07-02 661764494.05 983764232.86 2026-07-06 683326470.52 167378934.69 2026-07-07 525719444.66 433507901.98 2026-07-08 1142048850.69 451376707.10 2026-07-09 400427657.43 348575097.42 2026-07-10 677281266.53 1227744306.50 2026-07-13 255563800.35 499721382.96 2026-07-14 258600384.99 352790996.71 2026-07-15 722995679.68 1286086153.08 2026-07-16 323454409.27 245088972.17 2026-07-17 2016645565.72 468595415.99 2026-07-20 175166399.95 1037200883.72 2026-07-21 311215519.15 420721691.58 2026-07-22 255041796.62 1641306465.35 2026-07-23 341301811.76 172190479.45 2026-07-24 128974802.28 236607478.12 2026-07-27 350851382.43 311843284.19 2026-07-28 1312817274.89 525022206.28 2026-07-29 465653681.69 845539170.08 2026-07-30 857725473.64 249184449.55 2026-07-31 14141150953.27 13440909713.38 0.0357 2026-07-01 0.0357 2026-07-02 0.0357 2026-07-06 0.0357 2026-07-07 0.0357 2026-07-08 0.0356 2026-07-09 0.0355 2026-07-10 0.0355 2026-07-13 0.0355 2026-07-14 0.0355 2026-07-15 0.0356 2026-07-16 0.0357 2026-07-17 0.0357 2026-07-20 0.0357 2026-07-21 0.0357 2026-07-22 0.0357 2026-07-23 0.0358 2026-07-24 0.0359 2026-07-27 0.0359 2026-07-28 0.0360 2026-07-29 0.0360 2026-07-30 0.0360 2026-07-31 Y 881058.00 Non-financial corporation 0.0879 0.00 Broker-dealer 0.0868 0.00 N Treasury Master Fund Treasury Master Fund 81699K911 549300XQ6V293JKF0677 0001403166 81699K911 Investment Company Y 2026-08-03 2026-08-03 2026-08-03 N N N 0.0000 24436556417.04 24436556417.04 1.0000 N Y Y N The master-feeder funds are parties to a written daily liquidity agreement; consistent with SEC staff interpretative guidance, ownership interests in the master fund are categorized as a Daily Liquid Asset/Weekly Liquid Asset by the feeder funds. UBS Series Funds 2026-08-07 /s/Rose Ann Bubloski Rose Ann Bubloski Vice President