Long Eaton St Helens became members of the new Derbyshire Alliance in 1907, the league having been formed as a rebranded Mid-Derbyshire League. The following year they were founder members of the Notts & Derbyshire League, where they played until becoming founder members of the Central Alliance in 1911. They were champions of the league in 1912–13 before being renamed Long Eaton Town in 1914. In 1925 the club joined the Midland League, but left after two seasons.
Long Eaton Town were re-established in July 1949 and joined the Central Alliance, taking over the fixtures of Mansfield Town 'A' during the 1949–50 season. In 1954–55 the club finished bottom of Division One, although they avoided being relegated to Division Two. In 1956 financial problems led to the club being rebranded as Long Eaton United with a new strip and directors replacing a committee. League restructuring also saw the club moved into Division One South of the Central Alliance. They were Division One South runners-up in 1956–57 and champions in 1958–59.
Long Eaton United moved up to the Midland League in 1961. The club won the Derbyshire Senior Cup in 1964–65 and again in 1975–76, by which time they had become members of the Premier Division after it gained a second division in 1975, and were Premier Division runners-up the following season. In 1982 the Midland League merged with the Yorkshire League to form the Northern Counties East League, with Long Eaton placed in Division One South. After winning Division One South in 1984–85 the club were promoted to the Premier Division.
In 1989 Long Eaton left the Northern Counties East League to join the Supreme Division of the Central Midlands League. Despite finishing fifth in the division in their first season, they were demoted to the Premier Division. League reorganisation saw them playing in the Premier Division South in 1991–92 and then the Premier Division again in 1992–93, a season in which they finished fifth and were promoted back to the Supreme Division. After a third-place finish in the Supreme Division in 2001–02, the club moved up to Division One of the Northern Counties East League.
Long Eaton were Division One runners-up in 2003–04, earning promotion to the Premier Division. They were runners-up in 2008–09, also winning the League Cup. In 2014 the club transferred to the Premier Division of the new Midland League. In the league's 2014–15 they won the Premier Division Cup, beating Rocester 2–0 in the final.