The 2018 1. deild karla (English: Men's First Division) was the 64th season of the second-tier Icelandic football. Twelve teams competed in the league. The season began on 5 May and concluded on 22 September.
The league is contested by twelve clubs. Eight remained in the division from the 2017 season, while four new clubs joined the 1. deild karla:
Each team plays every opponent once home and away for a total of 22 matches per club, and 132 matches altogether.