N-MFP3 0001060517 XXXXXXXX 2026-08-31 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 42337237235.56 42337237235.56 0.9999 0.9999 2026-08-03 42410995658.86 42410995658.86 0.9999 0.9999 2026-08-04 42633944381.73 42633944381.73 0.9999 0.9999 2026-08-05 41350035004.57 41350035004.57 0.9999 0.9999 2026-08-06 41361720652.27 41361720652.27 0.9998 0.9998 2026-08-07 42431294538.72 42431294538.72 0.9999 0.9999 2026-08-10 42119781990.27 42119781990.27 0.9999 0.9999 2026-08-11 41929487095.64 41929487095.64 0.9998 0.9998 2026-08-12 41693882208.45 41693882208.45 0.9998 0.9998 2026-08-13 41631904333.98 41631904333.98 0.9997 0.9997 2026-08-14 42533018907.45 42533018907.45 0.9998 0.9998 2026-08-17 42551572338.71 42551572338.71 0.9998 0.9998 2026-08-18 42304071683.63 42304071683.63 0.9998 0.9998 2026-08-19 41648395902.05 41648395902.05 0.9998 0.9998 2026-08-20 42556606342.94 42556606342.94 0.9997 0.9997 2026-08-21 43485085975.94 43485085975.94 0.9998 0.9998 2026-08-24 42268630408.95 42268630408.95 0.9997 0.9997 2026-08-25 42039551548.62 42039551548.62 0.9997 0.9997 2026-08-26 40972538266.36 40972538266.36 0.9997 0.9997 2026-08-27 42089011265.30 42089011265.30 0.9996 0.9996 2026-08-28 41375435366.46 41375435366.46 0.9997 0.9997 2026-08-31 0.00 23126689633.18 0.00 0.00 72263635.02 23054425998.16 23053633745.9800 Y 1.0000 0.0374 2026-08-03 0.0374 2026-08-04 0.0374 2026-08-05 0.0373 2026-08-06 0.0372 2026-08-07 0.0372 2026-08-10 0.0372 2026-08-11 0.0372 2026-08-12 0.0372 2026-08-13 0.0372 2026-08-14 0.0373 2026-08-17 0.0373 2026-08-18 0.0373 2026-08-19 0.0373 2026-08-20 0.0373 2026-08-21 0.0373 2026-08-24 0.0373 2026-08-25 0.0374 2026-08-26 0.0374 2026-08-27 0.0374 2026-08-28 0.0375 2026-08-31 1.0001 2026-08-03 1.0001 2026-08-04 1.0001 2026-08-05 1.0001 2026-08-06 1.0001 2026-08-07 1.0001 2026-08-10 1.0001 2026-08-11 1.0001 2026-08-12 1.0001 2026-08-13 1.0001 2026-08-14 1.0001 2026-08-17 1.0001 2026-08-18 1.0001 2026-08-19 1.0001 2026-08-20 1.0001 2026-08-21 1.0001 2026-08-24 1.0001 2026-08-25 1.0001 2026-08-26 1.0001 2026-08-27 1.0001 2026-08-28 1.0001 2026-08-31 N N Single Class C000051800 50000000.00 23054425998.16 23053633745.9800 1.0001 2026-08-03 1.0001 2026-08-04 1.0001 2026-08-05 1.0001 2026-08-06 1.0001 2026-08-07 1.0001 2026-08-10 1.0001 2026-08-11 1.0001 2026-08-12 1.0001 2026-08-13 1.0001 2026-08-14 1.0001 2026-08-17 1.0001 2026-08-18 1.0001 2026-08-19 1.0001 2026-08-20 1.0001 2026-08-21 1.0001 2026-08-24 1.0001 2026-08-25 1.0001 2026-08-26 1.0001 2026-08-27 1.0001 2026-08-28 1.0001 2026-08-31 591715955.55 1023487315.27 2026-08-03 519845999.64 181601983.31 2026-08-04 342064283.91 367923005.00 2026-08-05 519800965.62 1586634873.94 2026-08-06 263552038.91 206946496.46 2026-08-07 786719768.35 170238675.63 2026-08-10 392389301.30 239229391.67 2026-08-11 153457501.29 629884523.64 2026-08-12 562601267.35 364272494.30 2026-08-13 504133251.92 599153714.21 2026-08-14 842452059.01 556979751.39 2026-08-17 638784665.99 274205588.37 2026-08-18 644613278.86 995929282.60 2026-08-19 357351467.66 518613403.31 2026-08-20 1148460705.14 550270158.27 2026-08-21 436729049.20 224568743.23 2026-08-24 414855768.29 1251431801.02 2026-08-25 417291219.83 890627482.14 2026-08-26 261300182.27 565577277.60 2026-08-27 1463825722.90 303521427.14 2026-08-28 425845347.63 1491512614.67 2026-08-31 11687789800.62 12992610003.17 0.0360 2026-08-03 0.0360 2026-08-04 0.0360 2026-08-05 0.0360 2026-08-06 0.0358 2026-08-07 0.0358 2026-08-10 0.0358 2026-08-11 0.0358 2026-08-12 0.0358 2026-08-13 0.0358 2026-08-14 0.0359 2026-08-17 0.0359 2026-08-18 0.0359 2026-08-19 0.0359 2026-08-20 0.0359 2026-08-21 0.0359 2026-08-24 0.0360 2026-08-25 0.0360 2026-08-26 0.0360 2026-08-27 0.0360 2026-08-28 0.0361 2026-08-31 Y 756356.00 Non-financial corporation 0.0744 0.00 Broker-dealer 0.0938 0.00 Other IND FID AS EXEC 0.0525 0.00 N Treasury Master Fund Treasury Master Fund 81699K911 549300XQ6V293JKF0677 0001403166 81699K911 Investment Company Y 2026-09-01 2026-09-01 2026-09-01 N N N 0.0000 23126689633.18 23126689633.18 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 2026-09-08 /s/Rose Ann Bubloski Rose Ann Bubloski Vice President