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: