2023 1. deild karla

The '''2023 1. deild karla' (English: Men's First Division'') was the 69th season of second-tier Icelandic football. The season began on 5 May 2023 and finished on 16 September 2023.

Twelve teams contested the league. The champions (ÍA) and play-off winners (Vestri) were promoted to the 2024 Besta deild karla. The bottom two teams (Ægir and Selfoss) were relegated to the 2024 2. deild karla.

Results
Each team played each other twice (22 matches each), once at home and once away.

1. deild karla play-offs
Teams placed 2nd-5th qualified for the play-offs, with the winners earning promotion to the 2024 Besta deild karla.