|Number of teams||104|
|Level on pyramid||4|
|Current champions|| FC Myllypuro |
| Finnish Football|
Kolmonen or III divisioona is the fourth level in the league system of Finnish football and comprises 104 Finnish football teams. The III divisioona was introduced in 1973 and in the mid-1990s became known as the Kolmonen (Number Three in English and Trean in Swedish).
There are 104 clubs in the Kolmonen, divided in 9 groups of 10 to 12 teams each representing a geographical area. During the course of a season (starting in April and ending in October) each club plays the others twice, once at their home ground and once at that of their opponents. The top team in each Kolmonen group is promoted to Kakkonen and the two lowest placed teams are normally relegated to the Nelonen.
The Football Association of Finland (Finnish : Suomen Palloliitto, SPL; Swedish : Finlands Bollförbund, FBF) administered the Kolmonen from 1973 until 1995. There were 9 sections which were divided on a regional basis with between 10 and 12 teams in each.
Since 1996 the administration of the Kolmonen has been delegated to the 12 district authorities of the SPL. Responsibilities for the 10 sections are divided as follows:
Teams within the Kolmonen are eligible to compete in the Suomen Cup and the Suomen Regions' Cup. The clubs are normally listed in an abbreviated form and their full names can be viewed by referring to the List of clubs or the relevant District Association.
Kaakkois-Suomi (South-East Finland)
Itä- and Keski-Suomi (Eastern Finland and Central)
Pohjois-Suomi (Northern Finland)
Keski-Pohjanmaa and Vaasa (Central Ostrobothnia and Vaasa)
Turku and Ahvenanmaa (Turku and Åland Islands)