The championship starts with a league stage and then progresses to a knock out stage. The draw for the group stages of the championship were made on 30 April 2018.[1]
Due to reconstruction of the stadium in 2018, Breffni Park was not used as a venue for any matches during this season's championship, except for the final.
All 12 teams enter the competition at this stage. A random draw determines which teams face each other in each of the four rounds. No team can meet each other twice in the group stage. The top 8 teams go into a seeded draw for the quarter-finals while the bottom 4 teams will enter a Relegation Playoff. If teams are level on points and a place in the quarter-final is at stake, a Playoff will be conducted to determine who goes through.
The 4 bottom placed teams the league phase will play off against each other. The 2 winners will maintain their senior status for 2019 while the 2 losers will face off in a Relegation-Final. The ultimate loser will be relegated to the 2019 Intermediate Championship.