Cossonay District was a district of the Canton of Vaud, Switzerland. The seat of the district was the town of Cossonay. It was dissolved on 31 August 2006.
Mergers and name changes
- On 1 January 1999 the former municipalities of Villars-Lussery and Lussery merged to form the new municipality of Lussery-Villars.
- On 1 September 2006 the municipalities of Bettens, Bournens, Boussens, Daillens, Lussery-Villars, Mex (VD), Penthalaz, Penthaz, Sullens and Vufflens-la-Ville came from the District de Cossonay to join the Gros-de-Vaud District.
- On 1 September 2006 the municipalities of La Chaux (Cossonay), Chavannes-le-Veyron, Chevilly, Cossonay, Cottens (VD), Cuarnens, Dizy, Eclépens, Ferreyres, Gollion, Grancy, L'Isle, Mauraz, Moiry, Mont-la-Ville, Montricher, Orny, Pampigny, Pompaples, La Sarraz, Senarclens and Sévery came from the District de Cossonay to join the Morges District.
Municipalities
{| class="wikitable"
!Municipality <br>
!Population <br><small>(2003-12-31)</small>
!Area<br><small>(km²)</small>
|-
| Bettens || align=right | 287 || align=right | 3.73
|-
| Bournens || align=right | 243 || align=right | 3.91
|-
| Boussens || align=right | 777 || align=right | 3.14
|-
| Chavannes-le-Veyron || align=right | 118 || align=right | 2.58
|-
| Chevilly || align=right | 203 || align=right | 3.89
|-
| Cossonay || align=right | 2696 || align=right | 8.32
|-
| Cottens || align=right | 346 || align=right | 2.36
|-
| Cuarnens || align=right | 430 || align=right | 7.17
|-
| Daillens || align=right | 634 || align=right | 5.56
|-
| Dizy || align=right | 207 || align=right | 3.03
|-
| Eclépens || align=right | 915 || align=right | 5.81
|-
| Ferreyres || align=right | 234 || align=right | 3.13
|-
| Gollion || align=right | 615 || align=right | 5.44
|-
| Grancy || align=right | 316 || align=right | 5.65
|-
| La Chaux (Cossonay) || align=right | 366 || align=right | 6.73
|-
| La Sarraz || align=right | 1739 || align=right | 7.77
|-
| L'Isle || align=right | 864 || align=right | 16.25
|-
| Lussery-Villars || align=right | 326 || align=right | 3.65
|-
| Mauraz || align=right | 37 || align=right | 0.50
|-
| Mex || align=right | 537 || align=right | 2.90
|-
| Moiry || align=right | 229 || align=right | 6.66
|-
| Mont-la-Ville || align=right | 331 || align=right | 19.75
|-
| Montricher || align=right | 730 || align=right | 25.94
|-
| Orny || align=right | 312 || align=right | 5.55
|-
| Pampigny || align=right | 849 || align=right | 11.08
|-
| Penthalaz || align=right | 2250 || align=right | 3.87
|-
| Penthaz || align=right | 1359 || align=right | 3.91
|-
| Pompaples || align=right | 677 || align=right | 4.45
|-
| Senarclens || align=right | 335 || align=right | 3.98
|-
| Sévery || align=right | 219 || align=right | 2.37
|-
| Sullens || align=right | 849 || align=right | 3.84
|-
| Vufflens-la-Ville || align=right | 1032 || align=right | 5.29
|}