William Frank Southall (2 July 1904 – 1 March 1964) was an English racing cyclist who won silver medals for Great Britain in the individual road race (run as an individual time trial) at the 1928 Summer Olympics and a track cycling medal at the 1932 Summer Olympics in Los Angeles. He also represented Britain in world championships from 1926 to 1933.

He was born in Wandsworth, London. He rode for the South London Norwood Paragon cycling club, broke numerous time trial and Road Records Association place-to-place records in domestic competitions, winning the first four British Best All-Rounder (BBAR) competitions from 1930 to 1933.