2015–16 Slovenian Third League

Competition format and rules

Slovenian Third League, also known by the abbreviation 3. SNL, was divided into four regional groups with a total of 52 participating clubs. Three groups (i.e. North, Centre, East) were composed of 14 clubs, while the group West only had 10 clubs that were participating in the competition. The winners of the regular season in each group played a promotional two-legged play-off to decide which two teams promoted to the Slovenian Second League. Reserve teams of the top division sides were ineligible to promote to the second division, due to the rules of the Football Association of Slovenia, which stipulated that one club's main squad and their reserve team must be at least two leagues apart in the country's football pyramid. Consequently, in case one club's main squad would get relegated from the top division to the second division their reserve team would be automatically relegated from the third division.

The number of relegated teams from each group was determined by the number of regional MNZ's from which the clubs in all four groups were a part of. There were nine MNZ's governing bodies in Slovenian football:

This meant that three teams from 3. SNL North were relegated at the end of the season and replaced by the winners of the fourth tier competitions held separately in MNZ Celje, MNZ Maribor and MNZ Ptuj. The number of relegated teams from 3. SNL Center and 3. SNL East was two, while only the bottom team relegated from 3. SNL West as MNZ Koper and MNZ Nova Gorica managed a combined fourth tier competition. The number of relegated teams was also determined by the location of teams which relegated from the second division. Each of the bottom placed second division teams could only relegate to the one 3. SNL group that was managed by the MNZ they were a part of.

Play-off

Two-legged play-off between winners for promotion to Slovenian Second League.

Second leg

Brda and Brežice 1919 were promoted to the Slovenian Second League.