| Competition: | 1. divisjon |
| Season: | 2012 |
| Dates: | 9 April – 11 November |
| Winners: | Start |
| Promoted: | Start Sarpsborg 08 |
| Relegated: | Tromsdalen Bærum Notodden Alta |
| Matches: | 240 |
| Total Goals: | 785 |
| League Topscorer: | Martin Wiig (20 goals) |
| Biggest Home Win: | Ranheim 7–0 Kongsvinger (20 May 2012) |
| Biggest Away Win: | HamKam 0–5 Kongsvinger (5 August 2012) |
| Highest Scoring: | HamKam 7–2 Tromsdalen (15 July 2012) Bærum 5–4 Bryne (9 September 2012) |
| Highest Attendance: | 5,760, at home match of Start[1] |
| Lowest Attendance: | 94, at home match of Bærum |
| Prevseason: | 2011 |
| Nextseason: | 2013 |
The 2012 1. divisjon (referred to as Adeccoligaen for sponsorship reasons) was a Norwegian second-tier football season. The season began on 9 April 2012 and ended on 11 November 2012.[2]
Two clubs, Start and Sarpsborg, were relegated from the 2011 Tippeligaen, while Notodden, Tromsdalen, Ull/Kisa, and Bærum were promoted from the 2011 2. divisjon.[3]
Asker, Nybergsund-Trysil, Randaberg and Løv-Ham were relegated to the 2012 2. divisjon
At the end of the season, the two best teams were promoted to the 2013 Tippeligaen, while the four worst placed teams were relegated to the 2013 2. divisjon.
| Team | Outgoing manager | Manner of departure | Date of vacancy | Table | Incoming manager | Date of appointment | Table | |
|---|---|---|---|---|---|---|---|---|
| Strømmen | Thomas Berntsen | Contract expired | 31 December 2011 | Pre-season | Erland Johnsen | 1 January 2012[4] | Pre-season | |
| Notodden | Brede Halvorsen | Resigned | 20 August 2012[5] | 14th | Kenneth Dokken | 24 August 2012[6] | 14th | |
| Bryne | Tommy Bergersen | Mutual consent | 10 September 2012 | 12th | Gaute Larsen | 10 September 2012[7] | 12th |
Start and Sarpsborg were directly promoted, and five teams entered a play-off for the last Tippeligaen spot in the 2013 season. These were:
The four Adeccoligaen teams first played a single game knockout tournament, with the winner (Ull/Kisa) advancing to a two-legged tie against the Tippeligaen team (Sandnes Ulf) for the 16th and final spot in the 2013 season. Sandnes Ulf retained their Tippeligaen spot with an aggregate 7–1 win over Ull/Kisa.
| Rank | Player | Club | Goals | Games | Average |
|---|---|---|---|---|---|
| 1 |  Martin Wiig | Sarpsborg 08 | 20 | 27 | 0.74 |
| 2 |  Matthías Vilhjálmsson | Start | 18 | 29 | 0.60 |
| 3 | Tore Andreas Gundersen | HamKam | 16 | 26 | 0.62 |
| 4 | Nicolay Solberg | Sarpsborg 08 | 14 | 30 | 0.47 |
| 5 | Øyvind Hoås | Sarpsborg 08 | 13 | 28 | 0.46 |
| 6 | Rozhat Shaswari | Bærum | 12 | 21 | 0.57 |
| Olav Tuelo Johannesen | Kongsvinger | 12 | 26 | 0.46 | |
| Håvard Lysvoll | Tromsdalen | 12 | 28 | 0.43 | |
| 9 | Robert Stene | Ranheim | 11 | 19 | 0.58 |
| Magnus Nikolaisen | Alta | 11 | 26 | 0.42 | |
 Ernest Asante | Start | 11 | 29 | 0.38 | |
| Thomas Lehne Olsen | HamKam | 11 | 30 | 0.37 | |
| 11 | Jim Johansen | Bodø/Glimt | 10 | 24 | 0.42 |
| Pål André Helland | Hødd | 10 | 26 | 0.38 | |
| Vegard Braaten | Bodø/Glimt | 10 | 28 | 0.36 | |
| Jo Sondre Aas | Sandefjord | 10 | 30 | 0.33 | |
Source: Alt om fotball