Margaret Wellington’s first major title was in 1946 when she beat the holder Vera Ellery to become the Southern Counties 440 yards freestyle champion. In 1947, Wellington was runner-up to Cathie Gibson in the ASA 220 yards, and that same year was part of the bronze medal 4 x 100 metres freestyle Great Britain relay team at the European Championships in Monte Carlo. A year later the British team finished fourth at the London Olympics. Also in 1948, Wellington finished runner-up to Gibson for the second successive year in the ASA 220 freestyle, and was also runner-up in the 440. She had a very productive year in 1950, collecting four medals at the British Empire Games in Auckland. She won silver in the 110 and 440 yards freestyle and 3 x 110y freestyle relay. She also won a bronze medal as part of the England 4 x 110 freestyle relay team. Wellington swam well into her later years, and spent the last six months of her life at the Elizabeth Court Nursing Home in Bexhill-on-Sea, where she died in 2015.