Blog · September 27, 2026
City of Chicago Maps and Plats
Chicago maps and plats are Cook County records. The parcel viewer shows the tax lot. The recorded plat shows how the block was divided.
Platbookmapper is an Amazon Associate. If you buy through an Amazon link on this page, we earn a commission. The link is a product, not the county map.
City of Chicago maps and plats are Cook County records for lots inside Chicago, Illinois. A plat is the recorded drawing of a subdivision or a resubdivision: lots, blocks, and easements. A parcel map is the assessor's current picture of those tax lots. Chicago addresses are full of subdivisions that have been re-cut, so the parcel number is the reliable handle.
Cook County is the county to open. A collar-county viewer will not contain a Chicago lot.
How to open them
- Go to the Platbookmapper home page and search Cook County.
- Or open the Illinois county directory and choose Cook County.
- Follow the official GIS link and search the Chicago site address or the PIN on the tax bill.
- With the PIN or the subdivision name, look up the recorded plat on the county recorder's site.
Platbookmapper only links out to the local parcel and lot-line GIS map. It does not store Chicago plats, and the outline on the screen is not a boundary survey.
Not a survey. County GIS and tax parcel maps are assessment and planning layers. They are not a substitute for a recorded plat, deed, or licensed survey.