| Bill Mumm | |
| Birth Name: | William John Mumm |
| Birth Date: | 26 March 1922 |
| Birth Place: | Mokihinui, New Zealand |
| Death Place: | Westport, New Zealand |
| Occupation: | Sawmiller[1] |
| Relatives: | Dean Mumm (grandson) |
| School: | Summerlea Primary School |
| Ru Position: | Prop |
| Height: | 1.780NaN0 |
| Weight: | 90kg (200lb) |
| Repcaps1: | 1 |
| Reppoints1: | 0 |
| Repyears1: | 1949 |
| Ru Province1: | Buller |
| Ru Provinceyears1: | 1942–55 |
| Ru Provinceapps1: | 85 |
William John Mumm (26 March 1922 – 11 December 1993) was a New Zealand rugby union player. A prop, Mumm represented Buller at a provincial level. He was a member of the New Zealand national side, the All Blacks, in 1949, playing one test match against Australia.[2]
He later served as chairman of the Buller County Council[2] and was appointed an Officer of the Order of the British Empire in the 1990 Queen's Birthday Honours, for services to local government.