The 3 arrondissements of the Orne department are:[1]
- Arrondissement of Alençon, (prefecture of the Orne department: Alençon) with 111 communes. The population of the arrondissement was 84,879 in 2021.
- Arrondissement of Argentan, (subprefecture: Argentan) with 123 communes. The population of the arrondissement was 107,625 in 2021.
- Arrondissement of Mortagne-au-Perche, (subprefecture: Mortagne-au-Perche) with 151 communes. The population of the arrondissement was 84,469 in 2021.