The 2018–19 season was the 121st in the history of the Northern Football League, a football competition in England.
The league has operated two divisions in the English football league system, Division One at step 5, and Division Two at step 6.
After Team Northumbria resigned from the league and disbanded during the close season, Division One featured 16 clubs which competed in the division last season, along with three new clubs, promoted from Division Two:
Division Two featured 16 clubs which competed in the division last season, along with four new clubs: