Sandnes Ulf
Asane
Kongsvinger
Sogndal
Ranheim
Raufoss
Jerv
Strommen
Mjondalen
IK Start
Bryne
KFUM
Ullensaker/Kisa
Fredrikstad
Aalesund
Levanger
Hodd
Skeid
Moss
Ham-Kam
Stabaek
Tromsdalen
Lyn 1896
Stjørdals/Blink
Kristiansund BK
Nest-Sotra
Grorud
Egersund
Notodden
Lillestrom
Florø
SK Brann
Sandefjord
Odd BK
Tromso
Elverum
Haugesund
Honefoss
Follo
Baerum
Arendal
Stromsgodset
Valerenga
Bodo/Glimt
Viking FK
Oygarden FK
The Norwegian First Division, also called 1. divisjon (Norwegian: første divisjon) and OBOS-ligaen (due to sponsoring ties with OBOS), is the second-highest level of the Norwegian football league system. Each year, the top finishing teams in the 1. divisjon are promoted to the Eliteserien, and the lowest finishing teams are relegated to 2. divisjon.
1. divisjon was previously known as 2. divisjon (1963–1990) and replaced regional league Landsdelsserien (1951–1962) after the latter was dissolved after the 1961–62 season. The second tier was also prior to Landsdelsserien known as 1. divisjon (1948–1951). Formally, it was a semi-professional league. The tier has been restructured many times and consists of 16 teams at present.
Between 1963 and 1990, the second highest level in Norwegian football was named 2. divisjon. In 1991, due to rebranding of the top flight level in 1990, it was renamed to its initial name; 1. divisjon. 1. divisjon has been the name of this level ever since, except for periods when the league has had a sponsor-affiliated name. Between 2005 and 2013 the level was known as Adeccoligaen and from 2015 to 2020 the name is OBOS-ligaen.