2023 League of Ireland First Division

The 2023 League of Ireland First Division season was the 39th season of the League of Ireland First Division, the second tier of the Republic of Ireland's association football league.

The winners (Galway United) were promoted to the 2024 League of Ireland Premier Division. The runners-up (Waterford) were also promoted after winning the League of Ireland Premier Division play-off.

Overview
The First Division has 10 teams. Each side plays each other four times for a total of 36 matches in the season. The team that finishes in first place achieve automatic promotion to the Premier Division. Teams finishing second to fifth place will enter the play-offs to determine the side to contest for a place in the 2024 Premier Division against the ninth placed (second last) Premier Division team.

Team changes
Cork City were promoted to the 2023 Premier Division as 2022 First Division champions. Finn Harps were relegated from the 2022 Premier Division.

Additional teams
Newly formed Kerry F.C. successfully applied for a First Division licence to compete in the 2023 season.

Personnel and kits
Note: Flags indicate national team as has been defined under FIFA eligibility rules. Players may hold more than one non-FIFA nationality.