The league was formed in 1919,[1][2] the nine founding members being Phoenix, Leinster, Pembroke, Dublin University, Railway Union, Civil Service, U.C.D., County Kildare and the Royal Hibernian Military School.
Teams play each other twice per season, once at home and once away, with league positions determined on the basis of percentage of points gained out of possible total points.
These top 12 teams will play each other once in 2025 and then split into a top-half and bottom-half.
[8] The Top team in the First Team League at the end of 2025 will be promoted to the Premier League for 2026 replacing the bottom team in the Premier League (subject to accreditation standards and OCC determination on final composition).
[8] Premier League/Championship First Team League Source: Cricket Leinster