Union County Inmate Population
Union County does not run a single-county jail at the sheriff's office. Local adult jail custody is housed at Tri-County Regional Jail, a regional facility serving Champaign, Madison, and Union Counties. That point matters for population data. A person arrested in Marysville or elsewhere in Union County may be booked at Tri-County, while the Union County Sheriff'''s Office remains the local records, warrants, public-records, and transport hub.
The Union County inmate population also includes people who are no longer in local pretrial jail custody. Women sentenced to Ohio prison may be housed at Ohio Reformatory for Women in Marysville, but that prison is part of the Ohio Department of Rehabilitation and Correction, not the county jail roster. Felony offenders can also be placed at West Central Community Correctional Facility, a secure community-based correctional facility in Marysville. Each custody type has its own search path.
Union County Inmate Statistics
The most useful Union County jail figures come from the sheriff annual reports and the Miami Valley Jails provider row for Tri-County. The roster provider row showed 121 people in the whole Tri-County Regional Jail on June 24, 2026, with a 30-minute update interval. Union County'''s own jail contract is narrower: the 2025 and 2024 sheriff reports list a daily Union County allowance of 52 beds at Tri-County and a $45 daily charge for each overage bed.
| Measure | Figure | Source / Date |
|---|---|---|
| Tri-County roster population | 121 current inmates | Miami Valley Jails provider row, June 24, 2026 |
| Roster update interval | 30 minutes | Miami Valley Jails provider row, June 24, 2026 |
| Union County bed allowance | 52 beds per day | Union County Sheriff 2025 and 2024 annual reports |
| 2025 Union County inmate-days | 17,490 | Common Pleas plus Marysville Municipal totals in 2025 report |
| 2025 estimated Union County ADP | 47.9 | Calculated from 17,490 inmate-days divided by 365 |
| West Central CBCF capacity | 144 beds | West Central Community Correctional Facility |
Union County Jail Trends
The 2025 annual report shows why Union County jail use cannot be judged only by the full regional jail count. Union County was under its 52-bed allowance when the full year is averaged, yet monthly spikes still produced 311 overage bed-days and $13,995 in overage payments. December was the high point in that table, with 1,813 combined inmate-days and 201 overage bed-days.
The 2024 report points the other way. Its monthly daily-average table totals suggest about 54.1 combined Union County prisoners when Common Pleas and Municipal averages are combined and divided across the year. That is above the 52-bed allowance. The same research shows a consistent sex split by inmate-days: about 78 percent male and 22 percent female in both 2024 and 2025.
| Year / Period | Population Measure | What It Means |
|---|---|---|
| 2025 | 47.9 estimated ADP | Union County average was below the 52-bed allowance overall. |
| 2025 | 311 overage bed-days | Monthly peaks still exceeded the allocation. |
| 2024 | 54.1 approximate combined ADP | Common Pleas and Municipal averages were above the allowance. |
| June 24, 2026 | 121 at Tri-County | Whole regional jail count, not just Union County prisoners. |
Union County Jail Capacity
Union County'''s capacity issue is contractual, not just physical. The regional jail can show a whole-building count while Union County tracks its own daily allowance and overage payments. The sheriff reports state that Union County pays $45 per bed per day when the local share exceeds the 52-bed daily allotment. That creates a local budget concern even when the Tri-County provider row is not framed as an overcrowding warning.
West Central Community Correctional Facility adds another capacity point, but it serves a different population. The official West Central site calls it a 144-bed Community Based Correctional Facility for felony offenders from Union and seven other counties. It is a secure treatment facility and local prison alternative, not the jail booking population for new arrests.
Union County Jail Laws
Ohio law explains why jail records, population data, and custody events are split among public offices. Ohio Revised Code 149.43 is the Public Records Act, which requires public records to be available for inspection and copying unless an exemption applies. Union County Sheriff Records applies that rule to specific existing sheriff records, including many records created by the office.
Ohio jail standards also shape the population data. OAC 5120:1-7-01 covers jail bureau authority and reporting of deaths, suicides, and critical incidents. OAC 5120:1-7-02 defines local jail types and security classifications. OAC Chapter 5120:1-8 sets minimum standards for full-service jails, and OAC 5120:1-8-09 requires emergency medical, dental, and mental-health care.
Access rule: Ask the office that keeps the record. Current custody starts with Tri-County, sheriff-created records route to UCSO Records, felony cases route to the Clerk of Courts, and municipal cases route to Marysville Municipal Court.
Search Union County Inmates
The local custody search starts with the Tri-County Regional Jail current-custody roster. The roster is hosted on the Miami Valley Jails platform and covers people currently in custody at listed jail providers. It is not a statewide criminal-history database. It is also not the right search for a person already transferred to ODRC, federal custody, immigration custody, or a court-ordered treatment facility.
- Open the Tri-County roster from the county or jail site and confirm the provider row says TRI-JAIL or Tri-County Regional Jail.
- Use the A-Z last-name links if the list loads, or complete the human security check if the CAPTCHA appears.
- Check the provider phone, update interval, and last-update time before treating a result as current.
- If no result appears, call Tri-County at 937-834-5000 or use a records request before assuming the person was not arrested.
- Use the ODRC, BOP, ICE, court, or VINE channels when the custody type has changed.
Union County Roster Fields
The public provider page exposes the search path and provider fields, but the current-inmate list and profiles were blocked by a human security check during research. That means profile-level booking details should be verified in a browser or by phone. The visible fields still help a reader confirm that the right jail provider has been selected.
| Field Label | Type | Required | Notes |
|---|---|---|---|
| Search by Last Name | A-Z link filter | Optional | Browse current custody by last-name initial when access is allowed. |
| Last / First | Sort controls | Optional | Visible as list headers or controls on the provider page. |
| Type the code shown | CAPTCHA text entry | Required when shown | The site requires users to prove they are human and allow session cookies. |
| Provider code | Provider row | Reference | TRI-JAIL identifies Tri-County Regional Jail. |
| Population / update | Provider row | Reference | Shows the current provider count, phone, update interval, and last update. |
Union County Custody Paths
Each locator answers a different question. Tri-County answers current local jail custody. ODRC answers Ohio prison custody, supervision, judicial release, and violator-at-large status. The BOP Inmate Locator covers federal prisoners from 1982 to present. ICE Online Detainee Locator System searches immigration detention by A-number or name details, and USAGov recommends contacting ICE Enforcement and Removal Operations if no match appears.
| System | Use It For | Do Not Use It For |
|---|---|---|
| Tri-County roster | Current local jail custody for Union, Champaign, and Madison inmates | Sentenced Ohio prison custody |
| ODRC Offender Search | Ohio prison, APA supervision, released, and violator records | Fresh Union County booking intake |
| BOP locator | Federal prison custody and federal release information | County mugshots or local bond status |
| ICE ODLS | Immigration detention lookup | State prison or county jail booking photos |
Union County Booking Records
Booking begins after arrest, warrant service, or court remand. For adult local custody, the person is usually transported to Tri-County Regional Jail. The sheriff'''s Court Services Division handles prisoner transports to and from detention facilities and hearings, and the 2025 annual report lists 906 total transports. Court Services is the bridge between jail custody and the Union County courts.
If the roster does not show a person, the record may not be online yet, the person may have been released, or the custody may have moved to another system. The Union County Sheriff'''s public-records page says written forms are recommended but not required. Requests can be mailed, emailed to sheriffpublicrecords@unioncountyohio.gov, or made by phone at 937-645-4100 ext. 4468. Ask for a specific existing record, such as a booking record or incident report.
The background-check page adds a useful limit: local criminal background checks are name-based and do not include arrests from other jurisdictions. Results show the offense, offense date, and the court where charges were filed. Final dispositions must be checked with the court.
Union County Detention Facilities
Union County has one primary local jail provider and two adult correctional facilities that often confuse inmate searches because they are tied to different stages of custody. The names are similar enough that wrong-door searches are common.
- Tri-County Regional Jail holds Union County pretrial detainees and locally sentenced adults along with Champaign and Madison County inmates.
- Ohio Reformatory for Women is an ODRC state prison in Marysville for sentenced women in Ohio prison custody.
- West Central Community Correctional Facility is a 144-bed secure treatment facility for felony offenders from Union and nearby counties.
Union County Jail Services
Tri-County'''s public site documents several service vendors. Inmate phone accounts use ICSolutions, with web, app, and phone funding available. Commissary, telephone, and tablet trust deposits route through Access Corrections or the Access Corrections app, and the lobby kiosk requires an Access Corrections login or account creation. All visits are by video visitation through JailATM, according to the jail homepage.
Ohio VINE is a notification tool, not a roster replacement. It gives custody-status notice for covered ODRC, Department of Youth Services, and county jail events such as release, transfer, escape, return from escape, or death. Registration is available through VINELink or by calling 800-770-0192.
Union County Inmate FAQ
How large is the Union County inmate population? The 2025 sheriff report supports an estimated Union County average daily population of 47.9 at Tri-County, based on 17,490 inmate-days. The whole Tri-County provider row showed 121 inmates on June 24, 2026.
Where are Union County inmates held after arrest? Adult local custody is normally at Tri-County Regional Jail in Mechanicsburg. The sheriff and courts are in Marysville, so do not assume the jail is at the courthouse or sheriff's office.
Can released inmates be searched online? The Tri-County roster is current-custody focused. For older booking records, use a specific public-records request to UCSO Records or check the relevant court case for charges and disposition.
Are mugshots guaranteed on the roster? No. The roster was CAPTCHA-gated during research, and no separate official Union County mugshot gallery was found. Booking photos may be requested as public records when no exemption applies.