The club was established as Birkenhead in 1960 before it amalgamated with Birkdale in 1963, taking its current name as Birkenhead United. Since 1965, Birkenhead have mainly played either in
Division 1 or
Division 2 of the Northern League though they twice early on, made it into
Premier Division in 1968 and 1970, only to be relegated again that same year. They wouldn't repeat that success in the cup again until
2010. Again going down in the 5th round, this time to
Glenfield Rovers. Birkenhead started to see more success in the 2010s, with them again making the
Premier Division in 2013 and they have stayed there since. They have just missed out on winning the division four times in 2013, 2014, 2016 and 2017. and
2013 they made the quarter-finals.
2015 they made the semi-finals, only losing 3–4 on penalties to
Napier City Rovers, before they finally won the cup in
2016, beating local rivals
Waitakere City 3–2 in extra time. They wouldn't have to wait very long before they won the cup again, when in the
2018 Chatham Cup, they made the finals. This time they were facing Wellington side
Western Suburbs and after 120 minutes the score was tied 1–1 before Birkenhead prevailed on penalties 5–4 to claim the cup for a second time in three years. In 2021, the club formed a strategic partnership with
Scottish Premiership outfit
St Mirren FC, alongside
Nelson Suburbs. ==Season by season record==