Inmate Search

Finding out whether someone is in the Cook County Jail system can feel stressful and confusing, especially if you are doing it for the first time. This guide walks you through how the Cook County inmate search works, how to use the online inmate locator, what to expect when you want to visit someone in custody, how to check on discharge, and where to turn for phone and support information—all based on official Cook County Sheriff’s Office and Cook County Department of Corrections resources.

Get Oriented: How the Cook County Inmate Search System Is Organized

Before you jump into a search, it helps to understand who runs what behind the scenes:

The Cook County Sheriff’s Office (CCSO) oversees law enforcement and the operations of the Cook County Jail.

The Cook County Department of Corrections (CCDOC) manages the day-to-day operations of the jail and maintains information about individuals in custody.

The Individual in Custody Locator is the official tool you use to search for someone held in the jail system.

The Cook County IL inmate search process centers around this locator. Once you understand what information it needs and how it connects to visitation, discharge, and phone services, you can move through the process much more confidently.

Use the Online Individual in Custody Locator the Right Way

The main place to start any Cook County inmate search is the online Individual in Custody Locator. This is the official search system for the Cook County Jail.

You can go directly to the official Individual in Custody Locator search page at
official Individual in Custody Locator search page.

On that page, you’ll see that you can search in one of two ways: by name or by booking number.

Choose Between Name Search and Booking Number Search

When you open the locator, you will see simple fields:

Full First Name (Required)
Full Last Name (Required)
OR
Booking ID

You must either enter the full first and last name or use the booking number—one method or the other.

Name search is best when:

You do not know the booking number.
You only recently learned that someone may be in custody.
You’re helping a family member or friend and only have their full legal name.

Booking number search is best when:

You received paperwork from law enforcement or the court that lists a booking ID.
You want the fastest, most direct route to one specific person in the system.

Format the Booking ID Correctly

The system is strict about how you type in the booking number. The instructions on the locator note that you should not use any hyphen in the Booking ID.

For example:

Correct: 20250043394
Incorrect: 2025-0043394

If you enter the number with a hyphen, the system may not return any result even if the person is in custody. If your first search fails, double-check the format against the instructions on the page and try again without punctuation.

Double-Check Names Before You Submit

If you are using the name search, the locator requires full first and full last name. To improve your results:

Use the person’s legal name, not a nickname.
If they have multiple last names, use the version listed on court or arrest paperwork.
Be careful with spelling—small typos can produce no results.

Once the information is entered, click Submit to run your Cook County inmate search.

Review What Your Cook County Inmate Search Tells You

After a successful search, you’ll see entries that match the information you entered. While the exact display can vary, you can generally expect to see:

The individual’s name
Booking or case-related identifiers
Their custody status (for example, currently in custody or recently discharged)
Where in the Cook County Jail system they are being housed

This information is what you’ll use to:

Confirm that the person you’re searching for is actually in custody in Cook County
Prepare to schedule a visit
Check on whether they may have been discharged recently
Coordinate with attorneys and support services

For more background about how the jail and inmate information are managed, you can review the Cook County Department of Corrections information page at
Cook County Department of Corrections information page.

Take the Next Step: Use Your Search to Prepare for a Visit

Once you locate someone using the Cook County inmate search, the next common step is scheduling a visit. Cook County has a detailed visitation policy tied to the Individual in Custody Locator and requires a Visitor Application.

You must complete this application and be approved before you can visit an individual in custody.

Know Where to Get the Visitor Application

According to the visitation policy, you can obtain and submit a Visitor Application in several places:

Through the Cook County Sheriff’s Office website
At the divisional lobby where the person in custody is housed
At the entrance of any Cook County courthouse

While you can still pick up applications in person, it is strongly encouraged to submit the application using the official online Sheriff’s website. That approach usually makes the process simpler and easier to track.

You can also keep up with requirements and any policy changes by reading the updated visitor information for the Cook County Department of Corrections at
updated visitor information for the Cook County Department of Corrections.

Understand Who Has to Apply—and Who Does Not

The policy sets out specific rules for adults and minors:

Adults (18 and older) must complete and submit the Visitor Application and wait for approval before visiting.

Minors 17 years of age or under do not need to fill out an application. However:
They must be accompanied by a parent or guardian who has already been approved.
If the minor is high school age, they must present a current state or school photo ID.
One adult can accompany up to three children during a visit.

If the person in custody is discharged and later returns to the jail, you will need to submit a new application to visit them again.

Expect a Background Check and Waiting Period

Every Visitor Application is subject to a background check. Once you submit your application:

Allow seven (7) business days before asking about your status.

When you’re ready to check, you will contact the Visitor Information Center using the official phone number listed later in this guide.

Only after your application is approved can you schedule or attend in-person visits.

Avoid Common Reasons for Visitor Application Denials

The Cook County visitation policy also clearly lists reasons why applications are denied. Knowing these in advance can help you avoid problems.

Applications will be denied if:

The application includes invalid, inaccurate, or unverifiable information.

The applicant is a minor (17 or younger).

The applicant is within the first year of parole or probation.

The applicant is currently on house arrest.

The applicant is on bond or has an open criminal case, except for misdemeanor traffic cases.

The applicant was discharged from the Cook County Department of Corrections, the Illinois Department of Corrections, or another verified correctional facility within the last 60 days.

The applicant has an outstanding warrant, including immigration detainers, or has failed to keep required registrations (for example, sex offender or violent offender registries) up to date.

There is a protective order in place between the applicant and the person in custody they want to visit.

A Cook County Sheriff’s Office supervisor identifies safety or security reasons to deny the visit.

The visitor fails to follow Cook County Department of Corrections visitor rules and regulations while on facility grounds.

If you are denied for reasons such as being in the first year of parole/probation or too recently discharged from a facility, you may be able to reapply after the mandatory waiting period ends.

Schedule the Actual Visit After Your Inmate Search

Once your Visitor Application is approved, you can move on to scheduling an in-person visit.

Cook County provides a dedicated site for setting up visits. You can schedule your in-person visit online through
schedule your in-person visit online.

From there, you can follow the prompts to pick available dates and times, based on the division where the person in custody is housed and the current visitation rules.

Because policies can change, it’s a good idea to cross-check your plans with both:

The information shown in the Individual in Custody Locator
The updated visitor information page mentioned earlier

Use the Inmate Search Together with the Individual in Custody Locator Home Page

Beyond the direct search link, the broader Individual in Custody Locator home page helps you understand more about how the system works and how visitation ties into it.

You can visit the
Individual in Custody Locator home page
to access:

The search function for individuals in custody
Links to visitation terms, rules, and frequently asked questions
Additional sections such as discharge and rules and regulations

This central hub is especially useful if you are navigating between searching, reading rules, and preparing for a visit all in one session.

Check on Release: Use Discharge Tools Alongside Your Inmate Search

Sometimes your goal is not just to see if someone is currently in custody, but to verify whether they have been released, or to track an upcoming discharge.

Cook County provides a dedicated Individual in Custody Discharge tool for this purpose. You can use this to confirm information related to people who have been discharged from the jail.

To look into discharge details, visit the
Individual in Custody Discharge search page.

Using this page together with your inmate search can give you a clearer picture of whether:

A person is still in custody
They have recently been discharged
Discharge information may be relevant to court dates, re-incarceration, or visitation

Set Up Phone Contact with Someone in Custody

For many families, staying in touch by phone is just as important as visiting. Cook County uses a phone service provider system for calls from individuals in custody, and the Sheriff’s Office publishes up-to-date information about accounts and calling rules.

For details on how phone accounts work, how to deposit funds, and what to expect from phone calls, review the
official guidance on individual in custody phone accounts.

This official information helps you:

Understand how calls are billed
Learn what options you have to receive calls
Avoid common issues, such as blocked numbers or account problems

When you combine this with your Cook County inmate search results, you can plan both visits and phone communication more effectively.

Explore Additional Information on Jail Operations and Inmate Services

The Cook County Sheriff’s Office provides more than just inmate search tools. The broader Department of Corrections resources can answer many questions related to jail operations, programs, and services.

On the Cook County Department of Corrections information page, you can find general explanations about the facility, visitation, and the Individual in Custody Locator, all maintained directly by the Sheriff’s Office.

If someone in custody is struggling with substance use, Cook County also offers education and assistance resources. You can learn more about these efforts through the
substance use and opioid crisis resources provided by the Sheriff’s Office.

These resources are especially important if you are trying to support someone in custody over the long term, not just locate them.

Reach the Sheriff’s Office for Questions About Your Inmate Search

If you still have questions after using the online tools—whether about your Cook County inmate search, visitation status, or general jail information—you can contact the Sheriff’s Office directly.

The best starting point for many users is the
Cook County Sheriff’s Office contact page.

From there you can:

See general contact methods for the Sheriff’s Office

Learn about which division handles which type of issue (police services, corrections, court services, and more)

Find additional information such as frequently asked questions and directions for specific requests

If you need official records or documents that are not available online, you may also need to use the Freedom of Information Act process. The Sheriff’s Office provides a dedicated page for that as well, which explains how to submit requests and subpoenas. You can review the procedure on the
Freedom of Information Act request page for the Sheriff’s Office.

Inmate Search–Related Departments and Contact Details

Cook County Sheriff’s Office
3026 S. California Ave. Chicago, Illinois 60608
Phone: (312) 603-6444

Cook County Department of Corrections – Individual in Custody Information
3026 S. California Ave. Chicago, Illinois 60608
Phone: (773) 674-5245

Cook County Department of Corrections – Visitor Information Center
3026 S. California Ave. Chicago, Illinois 60608
Phone: (773) 674-8225

Cook County Inmate Search FAQs

How do I actually run a Cook County inmate search online?

To look someone up, start on the official Individual in Custody Locator. You can search either by full first and last name or by Booking ID—one method or the other, not both. The name fields expect the person’s legal name as it appears on court or arrest paperwork, not a nickname. If you have the Booking ID, enter it exactly as shown on official documents and follow the on-screen instructions to submit the search.

Why is the Cook County Booking ID format so strict?

The Booking ID field on the locator is very particular: it must be entered as a single string of numbers without any hyphens. If you type the number with punctuation or extra characters, the system may return no results even if the person is currently in custody. When a search fails, double-check every digit against your paperwork and re-enter it exactly as the instructions on the Individual in Custody Locator page explain.

How do I use my search results to schedule a visit?

Once you’ve found the correct person through the locator, you’ll see prompts to start the visitation process. Cook County requires a Visitor Application and a background check before in-person visits are approved. You begin by agreeing to the posted terms and then following the instructions linked from the locator to submit an application for that specific individual. After approval, you can pick a date and time for an in-person visit through the Sheriff’s official in-person visit scheduling page, which ties directly back to the inmate information in the locator.

Where can I get official rules about visits, phone calls, and jail operations?

For broader information connected to your search—such as visitation rules, jail procedures, and how the jail is organized—check the Sheriff’s Department of Corrections information page. For release status, use the dedicated Individual in Custody Discharge search. If you’re trying to set up phone contact after locating someone, review the Sheriff’s official phone account information page, which explains current rules and options for calls from the jail.