2025 League of Ireland First Division
The 2025 League of Ireland First Division, known as the SSE Airtricity Men's First Division for sponsorship reasons, was the 41st season of the League of Ireland First Division. The competition began on 14 February 2025, and concluded on 17 October 2025.
On 10 October, Dundalk won the title after a 3–0 win against Finn Harps.
Teams
Team changes
The team relegated to the First Division was Dundalk, the bottom-placed team of the 2024 League of Ireland Premier Division. They replaced the one team promoted from the 2024 League of Ireland First Division, champions Cork City.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.| Team | Manager | Captain | Kit manufacturer | Shirt sponsor |
| Athlone Town |  League tableResultsTeams play each other four times.Promotion/relegation play-offsThe First Division teams will contest the First Division semi-finals and final. The semi-finals were held over two legs, with the second-placed team facing the fifth-placed team and the third-placed team facing the fourth-placed team. The semi-final winners then contest the First Division final, with the winners ultimately facing the ninth-placed League of Ireland Premier Division team for the final place in the 2026 League of Ireland Premier Division. The promotion/relegation play-offs will take place from 24 October to 7 November 2025. BracketSemi-finalsTreaty United won 2–1 on aggregate ---- Bray Wanderers won 4–2 on aggregate FinalPromotion/relegation play-off |