Henman was born in Oxford, Oxfordshire, as the youngest of a family of three boys. Henman's father Anthony, a solicitor, was accomplished at various sports, including tennis, hockey and squash. His mother Jane, a dress designer, played Junior Wimbledon and introduced Tim and his elder brothers, Michael and Richard, to tennis as soon as they could walk on the family's grass tennis court. His great grandfather played at Wimbledon. His maternal grandfather, Henry Billington, played at Wimbledon between 1948 and 1951, and he represented Britain in the Davis Cup in 1948, 1950 and 1951. In 1901 his maternal great-grandmother, Ellen Stanwell-Brown, was reputedly the first woman to serve overarm at Wimbledon. His maternal grandmother, Susan Billington, appeared regularly at Wimbledon in the 1950s, playing mixed doubles on Centre Court with her husband Henry, reaching the third round of the ladies' doubles in 1951, 1955 and 1956.