Deal did not take part in the 1944–45 season, but spent the 1945–46 season in the East Division of the Eastern Section of the Kent County Amateur League, finishing as runners-up. They returned to the Kent League in 1946–47, when they became members of Division One. Despite finishing bottom in their first season, they were not relegated, and went on to win the league in 1953–54. They later won the League Cup in 1957–58, beating Margate in the final. When the league folded in 1959, Deal became founder members of the Aetolian League, and were runners-up in its first season. In 1963 the club moved up to Division One of the Southern League. However, after three seasons of struggle and finishing bottom of the division in 1965–66, they left the league to join the Premier Division of the Greater London League (a merger of the Aetolian League and the London League), in which they won the League Cup in 1967–68, and were runners-up in 1968–69. In 1970 league reorganisation saw them placed in the 'B' section of the league.