League of Ireland First Division
| Founded | 1985 |
|---|---|
| Country | Ireland |
| Number of clubs | 10 |
| Level on pyramid | 2 |
| Promotion to | League of Ireland Premier Division |
| Domestic cup(s) | FAI Cup |
| League cup(s) | League of Ireland Cup |
| Current champions | Cork City (2nd title) (2024) |
| Most championships | Drogheda United (5) |
| Website | SSEAirtricityLeague.ie |
| Current: 2025 League of Ireland First Division | |
The League of Ireland First Division, also known as the SSE Airtricity League First Division for sponsorship reasons, is the second-highest division in both the League of Ireland and the Republic of Ireland football league system. The division was formed in 1985 as it replaced the League of Ireland B Division as the League of Ireland's second level division. Since 2003 the First Division has operated as a summer league. The division is contested by 10 clubs.