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 on September 23, 2026.
Cooper County, Missouri, has about 17,000 residents (2024 Census Bureau estimate). A person kept in custody after an arrest in Cooper County is held at the county jail, run by the Cooper 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: Cooper County public records, Cooper County arrest records, Cooper County warrants, Cooper County criminal records, Cooper County court records, Missouri arrest records and Missouri inmate search.
Finding Someone in Custody in Cooper County
The county jail, run by the Cooper County Sheriff's Office, holds everyone kept in custody after an arrest in Cooper County, from every agency.
SearchSystems opened and checked the jail page of the Cooper County Sheriff's Office at coopermosheriff.com/detentionunit.html (page title: Cooper County Sheriff's Department), phone 660-882-2771, 200 Main Street Boonville, MO 65233, which answered when SearchSystems opened it on September 23, 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 660-882-2771.
The Cooper County Jail by the Numbers
On an average day in 2021 the jail held about 34 people, down from about 55 in 2019. Its rated capacity in 2019, the last year with a capacity figure, was 57 beds, and it ran at 96 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
Cooper County has about 17,000 residents (2024 Census Bureau estimate), so the jail holds about 20 people for every 10,000 residents.
Who Books People Into the Cooper County Jail
The Cooper County Sheriff's Office and the agencies that report for Boonville, Pilot Grove, Otterville and Prairie Home make the arrests that end in a booking in Cooper County.
The largest arrest counts reported to the FBI were Boonville's 130 for 2025, the Cooper County Sheriff's Office's 8 for 2025 and Prairie Home's 4 for 2025.
Together, the four agencies in Cooper County with all twelve months of 2025 on file reported 142 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 Cooper 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 Cooper County serves the sentence in a facility of the Missouri Department of Corrections, whose inmate locator is at web.mo.gov/doc/offSearchWeb.
Frequently Asked Questions
How do I find an inmate in Cooper County?
Ask the Cooper County Sheriff's Office at 660-882-2771; its jail page SearchSystems verified is at coopermosheriff.com/detentionunit.html.
How many people are in the Cooper 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 57 beds.
What is the phone number for the Cooper County jail?
660-882-2771, the number on the page of the Cooper County Sheriff's Office SearchSystems verified.
Where do people sentenced to prison in Cooper County go?
To a facility of the Missouri Department of Corrections; its inmate locator is at web.mo.gov/doc/offSearchWeb.
Is this the official Cooper 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.