The league began on Friday 24 February 2017 and concluded on 27 October 2017.
Limerick, the 2016 First Division champion and Drogheda United, winners of the promotion/relegation playoffs, were promoted to the league, both bouncing straight back after having been relegated the previous season.
On 22 December 2016, the Football Association of Ireland announced that the league would be restructured into two 10-team divisions from the 2018 season onwards, one of the recommendations made in the 2015 Conroy Report.
[5] This meant the cancellation of the promotion/relegation playoff and relegation at the end of the 2017 season of 3 teams, with only the champions of the First Division promoted in return.
[5] Note: Flags indicate national team as has been defined under FIFA eligibility rules.