The canton Montluçon-3 has 15 communes.
| Code | Name | Population ▼ |
|---|---|---|
| 03185 | Montluçon | 33 147 |
| 03195 | Néris-les-Bains | 2 368 |
| 03314 | Villebret | 1 335 |
| 03106 | Durdat-Larequille | 1 280 |
| 03161 | Marcillat-en-Combraille | 900 |
| 03047 | La Celle | 398 |
| 03233 | Saint-Genest | 386 |
| 03007 | Arpheuilles-Saint-Priest | 383 |
| 03167 | Mazirat | 273 |
| 03231 | Saint-Fargeol | 187 |
| 03280 | Terjat | 180 |
| 03261 | Sainte-Thérence | 179 |
| 03206 | La Petite-Marche | 167 |
| 03216 | Ronnet | 162 |
| 03244 | Saint-Marcel-en-Marcillat | 130 |