Besta deild karla /
Men’s First Division

• 12 teams
• play each other home and away before the league splits in half and they play each other once more
• bottom 2 teams in lower section are relegated

Lengjudeild karla /
Men’s Second Division

• 12 teams
• play each other home and away
• 1st place team is promoted as champion
• 2nd-5th compete in a play-off to determine who else is promoted
• bottom 2 teams are relegated
• Lengjudeild is named for sponsorship purposes

2.deild karla /
Men’s third Division

• 12 teams
• play each other home and away
• 1st place team is promoted as champion
• 2nd place is also promoted
• bottom 2 teams are relegated

3.deild karla /
Men’s Fourth Division

• 12 teams
• play each other home and away
• 1st place team is promoted as champion
• 2nd place is also promoted
• bottom 2 teams are relegated

4.deild karla /
Men’s Fifth Division

• 10 teams
• play each other home and away
• 1st place team is promoted as champion
• 2nd place is also promoted
• bottom 2 teams are relegated

5.deild karla /
Men’s Sixth Division

• 16 teams across 2 groups
• play each other home and away within the groups
• Top 2 in each group enter playoffs, where the semi-final winners will both be promoted and the final determines the champion of the division
• I’m currently unclear whether teams will be relegated to Utandeild

Utandeild karla /
Men’s Non-League Level

• A new part of the KSÍ league setup in 2025
• 7 teams
• play each other home and away
• I’m unsure if there is any promotion.

Besta deild kvenna /
Women’s First Division

• 10 teams
• play each other home and away before the league splits and they play each other once more
• The top section is the top 6 teams, whereas the bottom section is just 4 teams
• bottom 2 teams in lower section are relegated

Lengjudeild kvenna /
Women’s Second Division

• 10 teams
• play each other home and away
• 1st place team is promoted as champion
• 2nd place is also promoted
• bottom 2 teams are relegated
• Lengjudeild is named for sponsorship purposes

2.deild kvenna /
Women’s third Division

• 12 teams
• play each other once before a split
• I’m currently unsure whether the split is into 3 sections as it was in 2024 or in 2 sections as the league table on the KSÍ website would have me believe. TBC