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 2, 2026.
Sioux County, Iowa, has about 37,000 residents (2024 Census Bureau estimate). A person kept in custody after an arrest in Sioux County is held at the county jail, run by the Sioux 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: Sioux County public records, Sioux County arrest records, Sioux County warrants, Sioux County criminal records, Sioux County court records, Iowa arrest records and Iowa inmate search.
Finding Someone in Custody in Sioux County
A person kept in custody after an arrest in Sioux County is held at the county jail, run by the Sioux County Sheriff's Office, whichever agency made the arrest.
SearchSystems opened and checked the jail page of the Sioux County Sheriff's Office at siouxcountysheriff.com/jail-information (page title: Jail Information | Sioux County Sheriff), phone 712-737-3131, a site that blocks automated checks (HTTP 403), so open it in a browser.
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 712-737-3131.
The Sioux County Jail by the Numbers
On an average day in 2019 the jail held about 30 people. Its rated capacity in 2019 was 67 beds, and it ran at 45 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
Sioux County has about 37,000 residents (2024 Census Bureau estimate), so the jail holds about 8 people for every 10,000 residents.
Who Books People Into the Sioux County Jail
The Sioux County Sheriff's Office and the agencies that report for Sioux Center, Orange City, Rock Valley and Hawarden make the arrests that end in a booking in Sioux County.
The Sheldon Police Department is listed by the FBI across two counties including Sioux County, so its arrests are not broken out for Sioux County here.
The largest arrest counts reported to the FBI were the Sioux County Sheriff's Office's 211 for 2025, Sioux Center's 118 for 2025 and Rock Valley's 38 for 2025.
Together, the five agencies in Sioux County with all twelve months of 2025 on file reported 422 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 Sioux 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 Sioux County serves the sentence in a facility of the Iowa Department of Corrections, whose inmate locator is at doc.iowa.gov/inmate-family-services.
Frequently Asked Questions
How do I find an inmate in Sioux County?
Ask the Sioux County Sheriff's Office at 712-737-3131; its jail page SearchSystems verified is at siouxcountysheriff.com/jail-information.
How many people are in the Sioux County jail?
About 30 on an average day in 2019, the latest year in the Vera Institute's jail data, against a rated capacity of 67 beds.
What is the phone number for the Sioux County jail?
712-737-3131, the number on the page of the Sioux County Sheriff's Office SearchSystems verified.
Where do people sentenced to prison in Sioux County go?
To a facility of the Iowa Department of Corrections; its inmate locator is at doc.iowa.gov/inmate-family-services.
Is this the official Sioux 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.