William Sloper may refer to:William Sloper (c.1658–1743), deputy paymaster general and MP for several boroughs William Sloper (1709–1789), son of the above, MP for Great Bedwyn William Charles Sloper, son of the above, MP for St Albans William Thomson Sloper (1883–1955), American stockbroker and survivor of the sinking of the RMS Titanic