| Competition: | Eerste Klasse |
| Season: | 2012–13 |
| Relegated: | 2013–14 Tweede Klasse |
| Promotion To: | 2013–14 Hoofdklasse |
| Prevseason: | 2011–12 |
| Nextseason: | 2013–14 |
The 2012–13 Eerste Klasse season was the third edition of the Dutch fifth tier since the Topklasse was formed as the third tier in 2010.
A total of 84 teams participated in the league. As usual, the competition is divided into eleven divisions: five divisions played on Saturdays and six divisions played on Sunday.
The champion of each division was directly promoted to the 2013–14 Hoofdklasse. Saturday Champions were:
Sunday champions were: