Montana State Prison is a state prison in Deer Lodge, Montana, run by the Montana Department of Corrections. The state classifies it as maximum security. Federal facility data from 2020 put its capacity at about 1,495 beds.
Montana State Prison Address and Phone
- Facility type
- State prison
- Address
- 400 Conley Lake Rd, Deer Lodge, MT 59722Open in Google Maps
- Main phone
- (406) 846-1320
- Operated by
- Montana Department of Corrections
- County
- Powell County
How to Find an Inmate at Montana State Prison
People serving state sentences are listed in the state's offender search, not on county jail rosters. Search by last and first name, or by the state inmate number if you have it; the result shows where the person is held now, which can change after a transfer.
Visiting, Mail and Phone Calls
Visiting days, visitor approval, dress rules and the mailing format for letters are set by the Montana Department of Corrections and can change at short notice. Read the official facility page and call ahead before you travel.
Jails and Police Near Montana State Prison
Anyone arrested near Deer Lodge is booked into the county jail first; a state facility only receives people after sentencing, commitment or transfer.
Other State Prisons in Montana
Open status checked against the official cor.mt.gov facility listing in November 2026. Address and phone come from that listing or, where it shows none, from the federal HIFLD prison dataset. This page lists no inmates.