The Metropolitan League ran for twenty-two seasons between 1949–50 and 1970–71.
Eight new clubs joined the league in its second season;
Five new clubs joined the league in its third season;
Four new clubs joined the league for its fourth season;
Four new clubs joined the league prior to the start of the season;
One new club, Wokingham Town, joined the league prior to the start of the 1954–55 season.
One new club, Bedford Town reserves, joined the league prior to the start of the 1955–56 season.
Two new clubs joined the league prior to the start of the 1956–57 season;
Two new clubs joined for the 1957–58 season;
One new club, Arsenal 'A', joined the league for the 1958–59 season.
One new club, Canterbury City, joined the league for the 1959–60 season.
Two new clubs joined the league for the 1960–61 season;
Three new clubs joined the league for the 1961–62 season;
Two new clubs joined the league for the 1962–63 season;
Five new clubs joined the league for the 1963–64 season, whilst Crawley Town reserves replaced their first team, who had moved up to the Southern League;
Eight new clubs joined the league for the 1964–65 season;
Four new clubs joined the league for the 1965–66 season, whilst Dunstable Town reserves replaced the first team, who had moved up to the Southern League.
Three new clubs joined the league for the 1966–67 season;
No new clubs joined the league for the 1967–68 season, although Brentwood Town reserves replaced the first team, which had moved up to the Southern League.
Four new clubs joined the league for the 1968–69 season:
Three new clubs joined the league for the start of the 1969–70 season;
Woodford Town joined the league prior to the start of the its final season. At the end of the season five clubs moved up to the Southern League as it added a new second tier division, splitting the previous Division One into Division One North and Division One South.