Haverhill were runners-up in the Essex & Suffolk Border League Premier Division in 1946–47, and did the double in 1947–48, winning both the league and the league cup, beating Brightlingsea United 1–0 in the final. They finished runners-up again in 1950–51, and won the league for a second time in 1962–63, before going on to claim a second double the following season, beating Ipswich Town 'A' 3–1 in the League Cup final. In 1964 they joined the Eastern Counties League, and won the League Cup in their first season. In 1978–79 they won the Eastern Counties League title, with the final match against Chatteris Town being watched by 1,300 supporters, a club record at the time.