The British 400 metres athletics champions covers four competitions; the current British Athletics Championships which was founded in 2007,[1] the preceding AAA Championships (1880-2006), the Amateur Athletic Club Championships (1866-1879) and finally the UK Athletics Championships which existed from 1977 until 1997 and ran concurrently with the AAA Championships.
[2] The AAA Championships were open to international athletes but were not considered the National Champion in this list if they won the relevant Championship.
David Jenkins, with nine AAA titles, including eight successive titles between 1971 and 1978 and again in 1982, and a single UK Athletics Championships gold medal in 1980, is the most successful 400 metre athlete in British domestic history.
Linda Keough won eight national women's titles, five AAA and three UK championships; on three occasions she won both titles in the same year, but Valerie Ball's six successive AAA wins in the immediate post-war era where only one championship was available annually means she is normally considered the most successful domestic British female athlete in the event.
dual championships era 1977-1987 dual championships era 1988-1997 2007 to present nc = not contested