The Belgian Third Division B was one of the two leagues at the third level of the Belgian football league system, the other one being the Belgian Third Division A. This division existed from the 1952–53 until 2015–16 seasons and was played every year with 18 clubs from 2009. Prior to this, the third level in the Belgian football league system was called Promotion and was divided into four leagues of 16 clubs each and prior to the 1931–32 season, the Promotion was divided into three leagues. Due to restructuring, the Third Division was replaced by Belgian Second Amateur Division which plays as three leagues of 16 clubs each from the 2016–17 season.
| Club | Municipality | Province | Finishing position 2014–15 season[1] | |
|---|---|---|---|---|
| FCO Beerschot Wilrijk | Wilrijk | Antwerp | 1st of promotion C | |
| K. Berchem Sport | Berchem | Antwerp | 12th | |
| K. Bocholter V.V. | Bocholt | Limburg | 5th | |
| R.F.C. Union Calamine | La Calamine | Liège | 10th | |
| R. Cappellen F.C. | Kapellen | Antwerp | 1st | |
| R.U. Wallone Ciney | Ciney | Namur | 4th | |
| K. Diegem Sport | Machelen | Flemish Brabant | 14th | |
| K.S.C. Grimbergen | Grimbergen | Flemish Brabant | 15th | |
| R.R.C. Hamoir | Hamoir | Liège | 4th of promotion D | |
| K.S.K. Hasselt | Hasselt | Limburg | 7th | |
| Hoogstraten VV | Hoogstraten | Antwerp | 8th | |
| R.F.C. de Liège | Liège | Liège | 1st of promotion D | |
| KFC Oosterzonen Oosterwijk | Westerlo | Antwerp | 9th | |
| Tempo Overijse | Ternat | Flemish Brabant | 1st of promotion B | |
| R. Sprimont Comblain Sport | Sprimont | Liège | 2nd | |
| K.V.K. Tienen | Tienen | Flemish Brabant | 13th | |
| R. Wallonia Walhain CG | Walhain | Walloon Brabant | 6th | |
| K.V. Woluwe-Zaventem | Zaventem | Flemish Brabant | 18th of second division |
— Refused promotion by declining to apply for a remunerative license
— R.R.C. Hamoir won in the first round of the Promotion play-off