During his career, Nat Flatman won many important Thoroughbred horse races in England including ten Classics. Often recorded as "E. Flatman," in France he is listed as Edward Flatman who traveled there to compete in several major races. Included in his French successes were three wins in the then most prestigious horse race in France, the Prix du Jockey Club, and two wins in the most prestigious race for fillys, the Prix de Diane.
Nat Flatman retired from racing in 1859 and died the following year. The epitaph on his headstone in All Saints Church, in the renowed English racing town of Newmarket states that he was "known to be honest, sober, discreet and plain living." The town later named a street in Nat Flatman's honour.