| Business | Phone |
| Mahnomen Cnty Historical Scty Mahnomen 56557 | (218) 935-5490 |
| Mahnomen County Bldg Mntnc 311 Nw Main St, Mahnomen 56557 | (218) 935-2787 |
| Mahnomen County Extension Svc 311 N Main St, Mahnomen 56557 | (218) 935-2226 |
| Mahnomen County Heartland Exp 311 N Main St, Mahnomen 56557 | (218) 935-2560 |
| Mahnomen County Highway Engr 1440 State Highway 200, Mahnomen 56557 | (218) 935-2296 |
| Mahnomen County Highway Mntnc 1440 State Highway 200, Mahnomen 56557 | (218) 935-5504 |
| Mahnomen County License Bureau 311 N Main St, Mahnomen 56557 | (218) 935-9347 |
| Mahnomen County Register-Deeds 311 N Main St, Mahnomen 56557 | (218) 935-5528 |
| Mahnomen County Road & Bridge 311 Nw Main St, Mahnomen 56557 | (218) 935-2882 |
| Mahnomen County Selective Svc 1440 State Highway 200, Mahnomen 56557 | (218) 935-5062 |
| White Earth Election Board 212 Se Main St, Mahnomen 56557 | (218) 936-5622 |