Historic Preservation in Cook County, IL (2026)

1 county-level rule, plus city-specific rules for 5 cities in Cook County, Illinois.

Verified from official government sources

Note: These county rules apply to unincorporated areas of Cook County. If you live within an incorporated city, that city's own rules apply: see the city list below.

Historic-Cultural Monuments

Cook County's Class L tax incentive rewards owners of landmark or contributing buildings with a reduced property assessment after substantial rehabilitation, once the property's municipality (or County Board if unincorporated) formally supports the project.

Cook County Class L Landmark Tax Incentive

Some Restrictions

Cook County Code § 74-63(17)

Real estate which is to be used for commercial or industrial purposes and which is designated as Class 3, Class 4, Class 5a or Class 5b pursuant to this Division; is a landmark or contributing building; and has undergone substantial rehabilitation. The substantial rehabilitation must constitute an investment by the owner of at least 50 percent of the building's full market value as determined b...

Full ordinance details →Official source ↗

Historic Preservation by City in Cook County

5 cities in Cook County have their own historic preservation rules. Each link goes to that city's dedicated page with code citations.

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