To do a Chicago building owner lookup, start with Cook County's property records: the Cook County Assessor and the Cook County Clerk are the offices to check for who is on record. Then use the City's building records by address to see permits and violations. If the owner is a company, or the records disagree, a title company or an attorney can run a title search. Records show the owner on file, which may not be who manages the building.
A Chicago building owner lookup starts with public records, and you do not need anyone's permission to use them. People ask because a neighbor's building is falling apart, because they are about to buy, or because they need to reach whoever is responsible for a porch, a wall or a notice. The routes below are general. We are not describing any office's website, because those change. For current steps and what each office offers, check with the Cook County Assessor and the Cook County Clerk directly.
Where do you look first?
Begin with the county, because property ownership is tracked at the county level.
- Get the address and, if you can, the PIN. The PIN is the property index number used for tax purposes. It is the cleanest way to be sure you are looking at the right parcel, especially on a street with similar addresses.
- Check the Cook County Assessor. The Assessor's office keeps property records for Cook County. Ask them or check their site for what they list for an address or a PIN, and whether it shows a name and mailing address.
- Check the Cook County Clerk. The Clerk's office is the place to ask about recorded documents, such as deeds, and how to search them. A deed is how a change of ownership gets put on the public record.
- Compare the names. A mailing address for property tax bills can differ from the building's address, and the name on file may be a person, a trust, or a company.
Treat anything you find as the owner on record, not necessarily the person you will meet at the door.
What can the City's records add?
The Department of Buildings (DOB) has a "Search Building Department Records" tool that lets you search permit, inspection and violation records by address (City of Chicago). It will not replace county ownership records, but it shows you the building's history: who pulled permits, whether there are open violations, and whether the building has been in the system before. Our article on looking up violations by address walks through it.
One caution if you are buying. The City's own Building Violations dataset says the data is historical, should not be relied on for real estate transactions, and may not reflect current condition, and it tells lenders and title companies to check the title commitment for outstanding enforcement actions (City of Chicago). If that is your situation, read buying a two-flat with open violations.
Why does the owner on record matter for violations?
In a building case at the Department of Administrative Hearings, the title typically names only the legal title holder, along with others in control of the property (City of Chicago). So when a violation exists, the owner on record is usually the name the case is built around. That is a statement about how cases are captioned, not about who is responsible in a particular situation. For that, ask an attorney. See also Chicago landlord laws that reach the building.
If you are trying to reach an owner because of a hazard, such as a loose porch or falling brick, the City takes reports through 311, which covers porch safety, construction without a permit, general safety and vacant or abandoned buildings (City of Chicago). You do not need to find the owner first.
What if the owner is a company or the trail goes cold?
Many buildings are held by a company or a trust, and the name on record may not tell you who runs it. A title company or a real estate attorney can run a title search and tell you what is recorded against the property. If the owner is a company, an attorney can also help you find how to reach it. Be respectful with what you find: use it for the reason you looked, which is usually to buy, to settle a repair question or to report a hazard.
For the bigger picture on what an owner or a buyer should know about the outside of the building, start with our landlord and buyer guide. If you are looking at a building and want the exterior assessed, our violation and repair team can walk it.
Common questions
Yes, ownership documents such as deeds are recorded in the public record at the county level. Check with the Cook County Clerk and the Cook County Assessor for how to search, because their tools and steps change over time.
Often, but the PIN is more reliable because it points to one parcel. The address can be used in the City's building records search to see permits and violations. For ownership, check Cook County's offices.
Call 311. The City takes reports on porch safety, construction without a permit, general safety and vacant or abandoned buildings, and the Department of Buildings decides what needs to be inspected.
Sources
- City of Chicago, Department of Buildings: Search Building Department Records
- City of Chicago, Department of Buildings and Department of Law: Building Code Violation Enforcement Process (PDF)
- City of Chicago Data Portal: Building Violations dataset
- City of Chicago, Department of Buildings: Department of Buildings home page
Facts last checked: October 7, 2026.
This article explains general rules and common situations in Chicago. It is not legal advice, and City rules change. For a specific property, check with the Chicago Department of Buildings or a licensed professional.