|Dates||15 May 2021 – 28 November 2021|
|Goals scored||258 (2.93 per match)|
|Top goalscorer|| Oscar Aga |
|Biggest home win|| Fredrikstad 4–0 Jerv |
(30 May 2021)
KFUM Oslo 4–0 Ull/Kisa
(31 May 2021)
Aalesund 5–1 Stjørdals-Blink
(22 June 2021)
Ranheim 4–0 Sandnes Ulf
(12 July 2021)
|Biggest away win|| Ranheim 0–4 Sogndal |
(12 June 2021)
|Highest scoring|| Bryne 5–2 Ranheim |
(19 May 2021)
|Longest winning run||4 matches|
|Longest unbeaten run||7 matches|
|Longest winless run||5 matches|
|Longest losing run||5 matches|
← 2020All statistics correct as of 14 July 2021.
The 2021 1. divisjon (referred to as OBOS-ligaen for sponsorship reasons) is a Norwegian second-tier football league season.
The league started on 15 May 2021, and is scheduled to end on 28 November 2021.
In the 2020 1. divisjon, Tromsø and Lillestrøm were promoted to the 2021 Eliteserien, while Kongsvinger and Øygarden were relegated to the 2021 2. divisjon.
Start and Aalesund were relegated from the 2020 Eliteserien, while Fredrikstad and Bryne were promoted from the 2020 2. divisjon.
|Aalesund||Ålesund||Color Line Stadion||10,778||Lars Arne Nilsen|
|Bryne||Bryne||Bryne Stadion||4,000||Jan Halvor Halvorsen|
|Fredrikstad||Fredrikstad||Fredrikstad Stadion||12,560||Bjørn Johansen|
|Grorud||Oslo||Grorud Arctic Match||1,700||Aksel Bergo|
|HamKam||Hamar||Briskeby Arena||7,800||Kjetil Rekdal|
|Jerv||Grimstad||Levermyr Stadion||3,300||Arne Sandstø|
|KFUM Oslo||Oslo||KFUM Arena||1,500||Jørgen Isnes|
|Ranheim||Trondheim||Extra Arena||3,000||Hugo Pereira|
|Raufoss||Raufoss||Nammo Stadion||1,800||Christian Johnsen|
|Sandnes Ulf||Sandnes||Øster Hus Arena||6,046|
|Sogndal||Sogndal||Fosshaugane Campus||5,622||Eirik Bakke|
|Start||Kristiansand||Sør Arena||14,448||Sindre Tjelmeland|
|Stjørdals-Blink||Stjørdalshalsen||M.U.S Stadion||2,000||Tom Dent|
|Strømmen||Strømmen||Strømmen Stadion||2,000||Ole Martin Nesselquist|
|Ull/Kisa||Jessheim||Jessheim Stadion||4,500||Arild Sundgot|
|Åsane||Bergen||Åsane Arena||3,700||Morten Røssland|
|Team||Outgoing manager||Manner of departure||Date of vacancy||Table||Incoming manager||Date of appointment||Table|
|Stjørdals-Blink||Roar Vikvang||Appointed head of Rosenborg's academy||31 December 2020||Pre-season||Tom Dent||1 January 2021||Pre-season|
|Ull/Kisa||Trond Fredriksen||Mutual consent||11 January 2021||Sindre Tjelmeland||12 January 2021|
|Grorud||Eirik Kjønø||Appointed assistant coach of Stabæk||4 February 2021||Aksel Bergo||1 March 2021|
|Start||Jóhannes Harðarson||Sacked||14 June 2021||7th||Sindre Tjelmeland||19 June 2021||12th|
|Ull/Kisa||Sindre Tjelmeland||Signed by Start||19 June 2021||11th||Arild Sundgot||1 July 2021||11th|
|Ranheim||Svein Maalen||Mutual consent||22 June 2021||15th||Hugo Pereira||7 July 2021||15th|
|Sandnes Ulf||Steffen Landro||Mutual consent||14 July 2021||16th|
|Pos||Team||Pld||W||D||L||GF||GA||GD||Pts||Promotion, qualification or relegation|
|1||HamKam||11||7||2||2||22||9||+13||23||Promotion to Eliteserien|
|3||Jerv||11||6||3||2||17||16||+1||21||Qualification for the promotion play-offs|
|14||Stjørdals-Blink||11||4||0||7||11||20||−9||12||Qualification for the relegation play-offs|
|15||Strømmen||11||2||5||4||8||12||−4||11||Relegation to 2. divisjon|
The 3rd to 6th placed teams will take part in the promotion play-offs; these are single leg knockout matches. In the first round, the 5th placed team will play at home against the 6th placed team. The winner of the first round will meet the 4th placed team on away ground in the second round. The winner of the second round will meet the 3rd placed team on away ground. The winner of the third round will advance to play the 14th placed team in Eliteserien over two legs in the Eliteserien play-offs for a spot in the top-flight next season.
The 14th placed team will take part in a two-legged play-off against the winners of the 2. divisjon play-offs to decide who will play in the 2022 1. divisjon.
1. divisjon or OBOS-ligaen 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.
The 2012 Tippeligaen was the 68th completed season of top division football in Norway. The competition began on 23 March 2012 and ended on 18 November 2012, with a summer break from 28 May to 30 June. Molde were the defending champions, while Hønefoss and Sandnes Ulf entered as the promoted teams from the 2011 1. divisjon. They replaced Start and Sarpsborg 08 who were relegated to the 2012 1. divisjon.
The 2012 1. divisjon was a Norwegian second-tier football season. The season began on 9 April 2012 and ended on 11 November 2012.
The 2015 1. divisjon was a Norwegian second-tier football league season. The league was contested by 16 teams, and the top two teams were promoted to Tippeligaen, while the teams placed from third to sixth place played a promotion-playoff against the 14th-placed team in Tippeligaen to win promotion. The bottom four teams were relegated to the 2. divisjon.
The 2016 1. divisjon was a Norwegian second-tier football league season. The league was contested by 16 teams, and the top two teams were promoted to Tippeligaen, while the teams placed from third to sixth place played a promotion-playoff against the 14th-placed team in Tippeligaen to win promotion. The bottom four teams were be relegated to the 2. divisjon.
The 2017 1. divisjon was a Norwegian second-tier football league season.
The 2018 season was Viking's 1st year back in 1. divisjon, after 29 consecutive seasons in the top flight of Norwegian football.
The 2018 1. divisjon was a Norwegian second-tier football league season.
The 2017 Eliteserien Promotion/Relagetion play-offs was the 44th time a spot in the Eliteserien was decided by play-off matches between top tier and second level clubs.
The 2019 1. divisjon was a Norwegian second-tier football league season.
The 2020 Eliteserien was the 76th season of top-tier football in Norway.
The 2020 1. divisjon was a Norwegian second-tier football league season.
The 2017 season was Bodø/Glimt's first season back in the OBOS-ligaen since 2013. Bodø/Glimt finished the season as Champions, earning promotion back to the Tippeligaen, whilst in the Norwegian Cup, they reached the Third Round before defeat to Elverum.
The 2021 season is Rosenborg's 42nd consecutive year in the top flight now known as Eliteserien, their 53st season in the top flight of Norwegian football. They will participate in Eliteserien, Cup and Europa Conference League entering at the Second Qualifying round. This will be Åge Hareide's first full season as Rosenborg manager. The start of the season was postponed from 5 April to 8 May due to the COVID-19 pandemic.