Three quarters of delegates backed a Central Council motion at Congress to introduce the change for the next three seasons.
Teams in Division Three and Four of the League will play in the new 16 team second tier, unless they reach their provincial final.
A Tipperary motion was carried to determine that Tier Two standings will be determined at the end of the League rather than at the start.
Irish Water Complete Mains Upgrades To Improve Output And Quality In Glenealy & Bray
Wicklow Carers Urged To Have Their Say Ahead Of Budget 2027
Suspended Bray GP Before The High Court Tomorrow
Young Wicklow Readers Celebrated at Ballywaltrim Library
Met Éireann Issues Status Yellow Rain Warning for Wicklow