IL · State directory
Illinois ADU rules
Official accessory dwelling unit regulations for 17 jurisdictions in Illinois, plus statewide law.
Not sure which city yet?
We have read the ordinances for 17 Illinois cities and lined them up side by side: detached vs internal, size limits, owner occupancy, and approval process.
Statewide ADU law
Illinois has state-level ADU legislation that applies across local jurisdictions. Local rules below may add requirements on top of state law.
- ilga.govOfficial sourceVerified August 2026https://www.ilga.gov/Documents/legislation/ilcs/documents/006500050K11-13-1.htm
- ilga.govOfficial sourceVerified August 2026https://www.ilga.gov/Documents/legislation/ilcs/documents/005500050K5-12001.htm
- ilga.govOfficial sourceVerified August 2026https://ilga.gov/Legislation/BillStatus?DocNum=3552&GAID=18&DocTypeID=HB&LegId=162242&SessionID=114
- ilga.govOfficial sourceVerified August 2026https://ilga.gov/documents/Legislation/PublicActs/104/PDF/104-0457.pdf
Cities
Aurora4 sources · verified August 2026Bloomington5 sources · verified September 2026Champaign4 sources · verified September 2026Chicago5 sources · verified August 2026Cicero3 sources · verified August 2026Elgin6 sources · verified August 2026Evanston5 sources · verified August 2026Joliet4 sources · verified August 2026Naperville5 sources · verified August 2026Oak Park6 sources · verified August 2026Peoria5 sources · verified August 2026Rockford6 sources · verified August 2026Schaumburg5 sources · verified August 2026Springfield5 sources · verified August 2026Urbana4 sources · verified August 2026Waukegan6 sources · verified August 2026
Counties & regions
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