Former West Ham player Sam Jennings was the first major signing, and the club won the United Counties League Cup in their first season.

After finishing ninth and reaching the first round of the FA Cup again (losing 4–1 in a replay at Newport County), the club was placed in the new Premier Division as the league reorganised.

However, this opportunity was declined in favour of a voluntary lateral movement, rejoining the United Counties League Premier Division instead.

At the start of the 1922–23 season the club began renting a field in Harecroft Road from a local landowner named Mr Overland, and permission was also obtained for the construction of a grandstand along one side of the pitch to boost attendances.

[3] Fenland Park opened in August 1947, with the grandstand and changing facilities from Harecroft Road having been transported to the new venue at a cost to the club of over £600.

At the start of the 1957–58 season, Fenland Park's record attendance of 8,044 was set on 25 August 1957 for a match against local rivals Peterborough United.

In March 2008 planning permission was granted by King's Lynn and West Norfolk Borough Council to build a new ground on a 9-acre (36,000 m2) site on the northern outskirts of the town.

In September 2008 the club left Fenland Park, and started playing at Outwell Swift's Nest ground after installing a seated stand, floodlights and terracing.

Construction began on the new ground in January 2010, with the first match, a 5–0 win over St Andrews in the FA Cup extra-preliminary round, taking place on 14 August 2010.