FCI Marion Federal Custody
FCI Marion is a Federal Correctional Institution operated by the Federal Bureau of Prisons. The official BOP facility data identifies Marion as a medium-security male institution in the North Central Region, with a minimum-security satellite camp. It is physically located in Williamson County, but it is not run by the Williamson County Sheriff's Office or Williamson County Jail. That distinction matters for every lookup question. County arrest records, Judici cases, IDOC records, and BOP prison records are separate systems.
The facility is used for federal custody. Most public lookup needs should start with the BOP inmate locator, which covers federal inmates incarcerated from 1982 to the present. The BOP locator does not show Williamson County jail booking charges, Illinois state prison commitments, county bond details, or local mugshots. It is designed to help identify a federal inmate and current BOP location. Federal mugshots are not published through the ordinary BOP locator.
FCI Marion's minimum-security camp should also be treated as BOP custody. Mail and visiting language may differ between the main institution and the camp, but both use federal rules. A family member should not call Williamson County Jail for a person held at FCI Marion, and a federal inmate at Marion should not be searched through a county roster.
The BOP facility page is the official source for the institution profile.
The FCI Marion page identifies the federal institution and links BOP resources for families and visitors.
This BOP source supports the federal custody role and should be used instead of county jail roster language.
FCI Marion Population
The BOP public facility endpoint reported current FCI Marion population data modified June 4, 2026. It listed 1,203 total inmates, with 997 at the main Federal Correctional Institution and 206 at the Marion Camp. That figure belongs to federal BOP custody. It should not be merged with the Williamson County Jail population, because the jail is a county facility for local custody and FCI Marion is a federal prison.
| Facility detail | Official BOP value |
|---|---|
| Facility type | Federal Correctional Institution |
| Security level | Medium, with minimum-security satellite camp |
| Gender | Male |
| Region | North Central Region |
| Population report date | June 4, 2026 |
The federal count is current in the BOP endpoint used for the research file. If BOP later updates the facility page or endpoint, the BOP number should control. The Williamson County home and facility pages should keep county jail and federal prison counts labeled separately.
Search FCI Marion Inmates
Use the BOP Federal Inmate Locator for FCI Marion inmate lookup. The by-name form captured in research includes first name, middle name, last name, race options, sex, and age. BOP also offers a find-by-number path, which is often stronger when the eight-digit register number is known. Do not use the Williamson County Jail phone or FOIA path as the primary search method for a federal prisoner housed at FCI Marion.
- Open the BOP Federal Inmate Locator and search by name or by federal register number.
- Use spelling variants, middle name, age, race, or sex only when they help narrow a common name.
- Confirm that the result is assigned to FCI Marion or Marion Camp before using Marion contact, mail, or visiting rules.
- If the person is not listed, consider whether they are in state custody, county custody, ICE custody, USMS pretrial custody, released, or outside BOP's 1982-present coverage.
Federal lookup results do not answer all local questions. The locator does not show Williamson County court case numbers, county booking photos, county bond terms, Illinois state charges, or local arrest details. For a local arrest that later became a federal case, the custody path may involve local booking, federal court, U.S. Marshals transport, and finally BOP designation.
The BOP locator is the correct search tool for federal inmates.
The BOP by-name locator captures federal search fields, not county jail roster fields.
The locator form reinforces why FCI Marion searches should use BOP identity data rather than Williamson County jail booking data.
FCI Marion Contact
FCI Marion's physical address is on Prison Road in Marion. The BOP endpoint also lists a fax number and executive assistant email. Inmate mail does not use the same street address as staff shipping or public directions. For records, visiting, mail, and money questions, match the purpose to the correct BOP channel before sending anything.
FCI Marion
4500 Prison Road
Marion, IL 62959
618-964-1441
Fax: 618-964-2058
Email: MAR-ExecAssistant-S@bop.gov
Directions from BOP route visitors from I-57 to IL-148 Exit 45, then toward Grassy Road and Prison Road. For release pickups, voluntary surrenders, and unescorted transfers, BOP directions say to stop near the small entrance building and use the call box by the red instruction sign for staff direction.
FCI Marion Visiting
BOP visiting rules apply at FCI Marion. The facility page links a general BOP visiting overview and facility-specific visiting schedule or procedures material. The research did not locate a visible weekly schedule in the BOP JSON endpoint, so a daily hour table should not be invented. BOP warns that special housing, safety conditions, severe weather, incidents, and warden restrictions can change or cancel visits. Call the facility before traveling.
| Visit item | FCI Marion federal detail |
|---|---|
| Schedule source | Use the FCI Marion facility page and linked visiting procedures. |
| Main institution | Federal BOP visiting rules and local procedures apply. |
| Satellite camp | Confirm camp-specific procedures before travel. |
| Changes or cancellation | Warden restrictions, safety issues, weather, and incidents can affect visits. |
| Before travel | Call 618-964-1441 and confirm approval, schedule, entrance, and identification rules. |
Do not use Williamson County Jail visiting hours for FCI Marion. County jail visits and federal prison visits follow different rules, different approval practices, and different security procedures. A person may also be at the camp rather than the main FCI, which can affect where family members report for visiting.
FCI Marion Mail and Money
The BOP communications page says federal inmates may use monitored phone calls, TRULINCS email, general and special mail, limited packages, and approved money-transfer methods. TRULINCS is text messaging, not full internet access, and messages are monitored. General mail can be opened and inspected. Special mail has separate marking rules and is opened in the inmate's presence when properly handled.
| Service | Official BOP detail |
|---|---|
| Main FCI inmate mail | Inmate Name and Register Number, FCI Marion, Federal Correctional Institution, P.O. Box 1000, Marion, IL 62959. |
| Camp inmate mail | Inmate Name and Register Number, FCI Marion, Federal Correctional Institution, Satellite Camp, P.O. Box 1000, Marion, IL 62959. |
| Staff mail | FCI Marion, P.O. Box 2000, Marion, IL 62959. |
| MoneyGram | Use register number plus last name and receive code 7932. |
| Western Union | Use Quick Collect, account number as register number plus last name, code city FBOP DC. |
| USPS money | Send acceptable instruments to the BOP Des Moines lockbox, not to FCI Marion. |
BOP money orders go to the centralized lockbox: Federal Bureau of Prisons, inmate name and register number, P.O. Box 474701, Des Moines, Iowa 50947-0001. Families should not send money to 4500 Prison Road or to the inmate mail P.O. Box unless BOP instructions specifically allow a type of correspondence there.
FCI Marion Intake
FCI Marion is not a street-arrest booking jail. A person usually reaches BOP custody after a federal court process, sentence, designation, transport, and intake into the federal prison system. Federal pretrial custody and transport may involve the U.S. Marshals Service. If a federal defendant has not yet reached BOP custody, the BOP locator may not show the person at FCI Marion. A missing BOP result can also mean the person is in state custody, county custody, ICE custody, released, or outside normal locator coverage.
- BOP
- The Federal Bureau of Prisons, which manages federal prisons such as FCI Marion.
- Register number
- The federal inmate number used for locator searches, mail, and money transfers.
- USMS
- The U.S. Marshals Service, often involved in federal pretrial detention and transport.
- Camp
- A minimum-security satellite facility tied to the main federal institution.
Once a person is designated to BOP and appears at FCI Marion, the BOP locator and facility rules become the core lookup tools. County jail records may still exist for a prior local booking, but they do not control federal custody status.
About FCI Marion
FCI Marion is important to Williamson County inmate population research because it creates a large federal custody population inside the county. The BOP population reported in June 2026 was far larger than the 2018 county jail inspection-day count, but those numbers describe different systems. The county jail handles local custody. FCI Marion holds federal male inmates, and its camp holds minimum-security federal inmates. IDOC handles sentenced Illinois prisoners in state custody.
Immigration detention is a separate federal path. The research did not confirm an ICE detention facility physically in Williamson County. If immigration custody is involved, use the ICE Online Detainee Locator System, not the BOP locator, unless the person is actually in BOP custody on a federal criminal sentence. Federal mugshots are not published through ordinary BOP lookup results, and FCI Marion should not be described as a county mugshot source.
Note: Confirm BOP location, visiting approval, mail format, and money instructions before sending funds or traveling to FCI Marion.