William Balmer was born in Liverpool in 1877. He played local football for Aintree Church and South Shore before joining Everton. He made his Football League debut against West Bromwich Albion in November 1897.
According to Tony Matthews, the author of Who's Who of Everton, Balmer was "a thickset defender" with a "crunching tackle". He played for the club at both full-back positions.
Balmer won his first and only international cap for England against Ireland on 25th February 1905. The England team that day also included Steve Bloomer, Richard Bond, Alex Leake, Charlie Roberts, Sam Wolstenholme and Vivian Woodward.
Everton had a good cup run in the 1905-1906 season beating Chesterfield Town (3-0), Bradford City (1-0), Sheffield Wednesday (4-3) and Liverpool (2-0). Everton beat Newcastle United 1-0 in the FA Cup Final played at Crystal Palace. Balmer won a winner's medal but was on the losing side against Sheffield Wednesday the following season in the 1907 final.
William Balmer died in 1937.