- PO Box 528 , Thief River Falls, MN 56701-0528 (source)
- PO Box 296 , Saint Hilaire, MN 56754-0296 (source)
- PO Box 171 , Goodridge, MN 56725-0171 (source)
- Pennington County Courthouse, 101 Main Ave N, Thief River Falls, MN 56701 (source)
NOTE: If a PO Box is listed, please check the link associated with the PO Box to look up the physical address.