United States Semiquincentennial Quarter Series Act This bill provides for the minting and issuing of certain coins for the semiquincentennial of the United States. The design of all coins currently authorized for minting and issuance by the Treasury may be changed to be emblematic of the celebration of the semiquincentennial beginning in January 1, 2026. The Department of the Treasury may issue quarter dollars in 2026 with up to five different designs emblematic of the semiquincentennial. One of the quarter dollar designs must be emblematic of a woman's or women's contribution to the birth of the Nation or the Declaration of Independence or any other monumental moments in American History. Treasury may mint and issue additional $1 coins emblematic of the semiquincentennial during a one-year period beginning January 1, 2026.