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 23, 2026 and October 2, 2026.
Marion County, Missouri, has about 28,000 residents (2024 Census Bureau estimate). A person kept in custody after an arrest in Marion County is held at the county jail, run by the Marion 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: Marion County public records, Marion County arrest records, Marion County warrants, Marion County criminal records, Marion County court records, Missouri arrest records and Missouri inmate search.
Finding Someone in Custody in Marion County
A person kept in custody after an arrest in Marion County is held at the county jail, run by the Marion County Sheriff's Office, whichever agency made the arrest.
SearchSystems opened and checked the jail page of the Marion County Sheriff's Office at marioncounty-mo.gov/departments/sheriff (page title: Marion County Sheriff | Marion County, Missouri), phone (573) 769-2077, Monday through Friday. 8:00 a.m. to 4:00 p.m., which answered when SearchSystems opened it on September 30, 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 (573) 769-2077.
The Marion County Jail by the Numbers
On an average day in 2021 the jail held about 86 people, down from about 92 in 2019. Its rated capacity in 2019, the last year with a capacity figure, was 90 beds, and it ran at 102 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
Marion County has about 28,000 residents (2024 Census Bureau estimate), so the jail holds about 30 people for every 10,000 residents.
Who Books People Into the Marion County Jail
The Marion County Sheriff's Office and the agencies that report for Hannibal and Palmyra make the arrests that end in a booking in Marion County.
The Monroe City Police Department is listed by the FBI across three counties including Marion County, so its arrests are not broken out for Marion County here.
The largest arrest counts reported to the FBI were Hannibal's 573 for 2024, the Marion County Sheriff's Office's 13 for 2025 and Palmyra's 7 for 2024.
Together, the two agencies in Marion County with all twelve months of 2024 on file reported 580 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 Marion County arrest records.
From the Jail to State Prison
A sentence of more than a year is served in state prison, not the jail; the Missouri Department of Corrections lists its inmates at web.mo.gov/doc/offSearchWeb.
Frequently Asked Questions
How do I find an inmate in Marion County?
Ask the Marion County Sheriff's Office at (573) 769-2077; its jail page SearchSystems verified is at marioncounty-mo.gov/departments/sheriff.
How many people are in the Marion County jail?
About 86 on an average day in 2021, the latest year in the Vera Institute's jail data, against a rated capacity of 90 beds.
What is the phone number for the Marion County jail?
(573) 769-2077, the number on the page of the Marion County Sheriff's Office SearchSystems verified.
Where do people sentenced to prison in Marion 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 Marion 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.