William Lewis Thomas (30 June 1913 — 1 February 1995 (aged 81)) born in Ystradgynlais, was a rugby union and rugby league footballer of the 1930s and '40s, playing club level rugby union (RU) for Ystradgynlais RFC, and Neath RFC, as a Scrum-half, and playing club level rugby league (RL) for Ystradgynlais RLFC. He captained Ystradgynlais RFC in 1937/38, and played for Neath RFC between the years of 1938 and 1941, and then for a further season in 1946.