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.
Jersey County, Illinois, has about 21,000 residents (2024 Census Bureau estimate). A person kept in custody after an arrest in Jersey County is held at the county jail, run by the Jersey 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: Jersey County public records, Jersey County arrest records, Jersey County warrants, Jersey County criminal records, Jersey County court records, Illinois arrest records and Illinois inmate search.
Finding Someone in Custody in Jersey County
A person kept in custody after an arrest in Jersey County is held at the county jail, run by the Jersey County Sheriff's Office, whichever agency made the arrest.
SearchSystems opened and checked the jail page of the Jersey County Sheriff's Office at jerseycounty-il.gov/sheriff-department (page title: Sheriff Department | Jersey County Government), phone 618-498-5571, 201 W Pearl St. Jerseyville, IL 62052, Monday: 7:30 AM to 9:00 PM, 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 618-498-5571.
The Jersey County Jail by the Numbers
On an average day in 2019 the jail held about 27 people. Its rated capacity in 2019 was 36 beds, and it ran at 74 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
Jersey County has about 21,000 residents (2024 Census Bureau estimate), so the jail holds about 13 people for every 10,000 residents.
Who Books People Into the Jersey County Jail
The Jersey County Sheriff's Office and the agencies that report for Jerseyville and Grafton make the arrests that end in a booking in Jersey County.
The Brighton Police Department is listed by the FBI across two counties including Jersey County, so its arrests are not broken out for Jersey County here.
The largest arrest counts reported to the FBI were Jerseyville's 101 for 2025, the Jersey County Sheriff's Office's 73 for 2025 and Grafton's 2 for 2025.
Together, the three agencies in Jersey County with all twelve months of 2025 on file reported 176 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 Jersey 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 Illinois Department of Corrections lists its inmates at idoc.illinois.gov/offender/inmatesearch.html.
Frequently Asked Questions
How do I find an inmate in Jersey County?
Ask the Jersey County Sheriff's Office at 618-498-5571; its jail page SearchSystems verified is at jerseycounty-il.gov/sheriff-department.
How many people are in the Jersey County jail?
About 27 on an average day in 2019, the latest year in the Vera Institute's jail data, against a rated capacity of 36 beds.
What is the phone number for the Jersey County jail?
618-498-5571, the number on the page of the Jersey County Sheriff's Office SearchSystems verified.
Where do people sentenced to prison in Jersey County go?
To a facility of the Illinois Department of Corrections; its inmate locator is at idoc.illinois.gov/offender/inmatesearch.html.
Is this the official Jersey 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.