Reviewed and updated October 9, 2026 by the SearchSystems.net editorial team. The arrest counts are the ones each agency reported to the FBI, as the FBI held them on October 8, 2026. The jail figures are from the Vera Institute of Justice's Incarceration Trends data. Every office link was opened and checked against the office's own site between September 24, 2026 and October 4, 2026.
Big Horn County, Montana, has about 13,000 residents (2024 Census Bureau estimate). A person kept in custody after an arrest in Big Horn County is held at the county jail, run by the Big Horn County Sheriff's Office, and the jail's record of each person held is a public record. This guide says where to look for someone in custody, what the jail holds and who books people into it.
This guide covers the search, the jail, who books people, state prison and common questions.
Related guides: Big Horn County public records, Big Horn County arrest records, Big Horn County warrants, Big Horn County criminal records, Big Horn County court records, Montana arrest records and Montana inmate search.
Finding Someone in Custody in Big Horn County
The county jail, run by the Big Horn County Sheriff's Office, holds everyone kept in custody after an arrest in Big Horn County, from every agency.
SearchSystems opened and checked the jail page of the Big Horn County Sheriff's Office at bighorncountymt.gov/176/Sheriff (page title: Sheriff | Big Horn County, MT), phone 406-665-9802, which answered when SearchSystems opened it on October 4, 2026.
That page is the office's jail information page rather than a roster, so a search for a particular person goes through the office at 406-665-9802.
The Big Horn County Jail by the Numbers
On an average day in 2021 the jail held about 34 people, down from about 41 in 2019. Its rated capacity in 2019, the last year with a capacity figure, was 37 beds, and it ran at 111 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
Big Horn County has about 13,000 residents (2024 Census Bureau estimate), so the jail holds about 27 people for every 10,000 residents.
Who Books People Into the Big Horn County Jail
The Big Horn County Sheriff's Office and the agency that reports for Hardin make the arrests that end in a booking in Big Horn County.
The largest arrest counts reported to the FBI were Hardin's 312 for 2025 and the Big Horn County Sheriff's Office's 142 for 2025.
Together, the two agencies in Big Horn County with all twelve months of 2025 on file reported 454 arrests to the FBI that year. Those kept in custody were booked into the county jail; a person cited and released at the scene was not.
The counts, agency by agency and year by year, are in Big Horn County arrest records.
From the Jail to State Prison
The jail holds people awaiting trial and people serving short sentences. A person sentenced to prison in Big Horn County serves the sentence in a facility of the Montana Department of Corrections, whose inmate locator is at offendersearch.mt.gov/conweb.
Frequently Asked Questions
How do I find an inmate in Big Horn County?
Ask the Big Horn County Sheriff's Office at 406-665-9802; its jail page SearchSystems verified is at bighorncountymt.gov/176/Sheriff.
How many people are in the Big Horn County jail?
About 34 on an average day in 2021, the latest year in the Vera Institute's jail data, against a rated capacity of 37 beds.
What is the phone number for the Big Horn County jail?
406-665-9802, the number on the page of the Big Horn County Sheriff's Office SearchSystems verified.
Where do people sentenced to prison in Big Horn County go?
To a facility of the Montana Department of Corrections; its inmate locator is at offendersearch.mt.gov/conweb.
Is this the official Big Horn County website?
No. SearchSystems.net is an independent public records guide, online since 1997. It links to the official county, court and state offices described above and does not hold records, charge for them or take requests.