| Business | Phone |
| Gis 525 W Fir Ave, Fergus Falls 56537 | (218) 998-8310 |
| Otter Tail Cnty Motor Vehicle 545 W Fir Ave, Fergus Falls 56537 | (218) 998-8080 |
| Otter Tail Cnty Voter Rgstrtn 510 W Fir Ave, Fergus Falls 56537 | (218) 998-8040 |
| Otter Tail County Detention 416 S Mill St, Fergus Falls 56537 | (218) 736-2057 |
| Otter Tail County Extension 219 W Cavour Ave, Fergus Falls 56537 | (218) 739-7130 |
| Otter Tail County Financial 535 W Fir Ave, Fergus Falls 56537 | (218) 998-8230 |
| Otter Tail County Highway Adm 419 S Court St, Fergus Falls 56537 | (218) 998-8470 |
| Otter Tail County Hwy Garage 23600 County Highway 1, Fergus Falls 56537 | (218) 736-6821 |
| Otter Tail County Land & Rsrc 540 W Fir Ave, Fergus Falls 56537 | (218) 998-8095 |
| Otter Tail County Land & Rsrc 565 W Fir Ave, Fergus Falls 56537 | (218) 739-2271 |
| Otter Tail County Management 550 W Fir Ave, Fergus Falls 56537 | (218) 998-8120 |
| Otter Tail County Mgmt Info 510 W Fir Ave, Fergus Falls 56537 | (218) 739-2271 |
| Otter Tail County Personnel 520 W Fir Ave, Fergus Falls 56537 | (218) 998-8060 |
| Otter Tail County Plant Oprtns 555 W Fir Ave, Fergus Falls 56537 | (218) 998-8050 |
| Otter Tail County Public Hlth 221 W Cavour Ave, Fergus Falls 56537 | (218) 739-2528 |
| Otter Tail County Recorder 565 W Fir Ave, Fergus Falls 56537 | (218) 998-8140 |
| Otter Tail County Veterans Svc 121 W Junius Ave # 140, Fergus Falls 56537 | (218) 998-8605 |
| Otter Tail Detention Facility 416 S Mill St, Fergus Falls 56537 | (218) 998-8556 |
| Otter Tail Support Collections 121 W Junius Ave, Fergus Falls 56537 | (218) 998-8640 |
| Otter Tail Support Collections 530 W Fir Ave, Fergus Falls 56537 | (218) 998-8640 |