Reviewed and updated October 10, 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 11, 2026.
Whiteside County, Illinois, has about 55,000 residents (2024 Census Bureau estimate). A person kept in custody after an arrest in Whiteside County is held at the county jail, run by the Whiteside 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: Whiteside County public records, Whiteside County arrest records, Whiteside County warrants, Whiteside County police reports, Whiteside County property records, Illinois arrest records and Illinois inmate search.
Finding Someone in Custody in Whiteside County
The county jail, run by the Whiteside County Sheriff's Office, holds everyone kept in custody after an arrest in Whiteside County, from every agency.
SearchSystems opened and checked the jail page of the Whiteside County Sheriff's Office at whitesidecountyil.gov/294/Sheriff (page title: Sheriff | Whiteside County, IL), phone 815-772-4044, 400 N Cherry St Morrison, IL 61270, Tuesdays 7 pm to 9 pm, which answered when SearchSystems opened it on October 11, 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 815-772-4044.
The Whiteside County Jail by the Numbers
On an average day in 2023 the jail held about 54 people, down from about 71 in 2019. Its rated capacity in 2023 was 129 beds, and it ran at 41 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
Whiteside County has about 55,000 residents (2024 Census Bureau estimate), so the jail holds about 10 people for every 10,000 residents.
Who Books People Into the Whiteside County Jail
The Whiteside County Sheriff's Office and the agencies that report for Sterling, Rock Falls, Morrison, Fulton, Prophetstown, Erie and two more cities make the arrests that end in a booking in Whiteside County.
The largest arrest counts reported to the FBI were Tampico's 1,152 for 2025, Sterling's 395 for 2025 and Rock Falls's 232 for 2025.
Together, the six agencies in Whiteside County with all twelve months of 2025 on file reported 1,958 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 Whiteside 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 Whiteside County serves the sentence in a facility of the Illinois Department of Corrections, whose inmate locator is at idoc.illinois.gov/offender/inmatesearch.html.
Frequently Asked Questions
How do I find an inmate in Whiteside County?
Ask the Whiteside County Sheriff's Office at 815-772-4044; its jail page SearchSystems verified is at whitesidecountyil.gov/294/Sheriff.
How many people are in the Whiteside County jail?
About 54 on an average day in 2023, the latest year in the Vera Institute's jail data, against a rated capacity of 129 beds.
What is the phone number for the Whiteside County jail?
815-772-4044, the number on the page of the Whiteside County Sheriff's Office SearchSystems verified.
Where do people sentenced to prison in Whiteside 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 Whiteside 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.