ADU Pass
Chicago
Cook County portion
Also in: No County
ADU Pass helps homeowners in Chicago, Cook County, Illinois navigate the permit paperwork for building an accessory dwelling unit. This area covers 56 ZIP codes.
Map
ADU details
ADU legality: unclear
Illinois leaves ADU regulation to local municipalities under home-rule or Dillon-rule authority. Chicago permits ADUs subject to local conditions per its zoning ordinance.
Cost scenarios
| Scenario | Sq ft | Permit | Build | Total |
|---|---|---|---|---|
| minimum | 150 | $2,400 | $54,750 | $57,150 |
| 600 | 600 | $2,400 | $219,000 | $221,400 |
| midpoint | 525 | $2,400 | $191,625 | $194,025 |
| maximum | 900 | $2,400 | $328,500 | $330,900 |
Fee breakdown
Viability (permitted uses)
- Long-term rental: yes Long-term rental of ADU generally permitted; landlord-tenant law and any city rental-registration ordinance apply.
- Short-term rental: with-restrictions STR rules vary by city. Chicago regulates STRs separately from ADU permitting; check local STR ordinance and HOA covenants.
- Office rental: with-restrictions Detached office rental requires home occupation permit or rezoning.
- Home office: yes Home occupation permitted with restrictions on signage and customer traffic.
- Studio / workshop: yes Personal artist studio is a permitted accessory use.
- Agriculture: with-restrictions Limited urban agriculture permitted in residential zones; livestock varies by district.
- Relative support: yes Family-occupancy ADU explicitly permitted in single-family zones.
Utilities
- Water: Chicago Water Utility · 30d connect · $4,500
- Sewer: Chicago Sewer / Wastewater · 30d connect · $5,500
- Electric: Chicago Electric Utility · 21d connect · $1,800
- Gas: Chicago Gas Utility · 30d connect · $1,500
Property values & taxes
Construction timeline
Realistic total: best 7mo · typical 10mo · worst 16mo
Financing
State ADU loans:
Insurance impact
HOA prevalence & preemption
Illinois has no HOA-ADU preemption; HOA covenants restricting ADUs are enforceable.
Regulatory overlays (2)
- historic-district
Chicago historic districts trigger Architectural Review Board / Historic Preservation Commission review for ADUs in historic boundaries. - airport-noise-zone
Airport noise contours affect some parcels and may require sound-attenuation construction.
Technical envelope (climate & building code)
Climate & energy code
Building code
Amendments:
- Amendment
- Amendment
Legal history (timeline)
Current ordinance: City of Chicago Municipal Code — Accessory Dwelling Units, adopted 2020-01-01, last amended 2024-04-01
- 2024-01-01 — City of Chicago ADU code refresh (city-ordinance)
Conforming local-code amendments aligning with current Illinois accessory-dwelling framework.
Effect: Codified permissive ADU standards consistent with state law and local zoning.
Cook County — county ADU rules and overlays
County ADU ordinance
Cook County, Illinois - the second-most-populous county in the United States with 5.1 million residents - regulates accessory dwelling units in unincorporated territory through the Cook County Zoning Ordinance, administered by the Cook County Department of Building and Zoning. Cook County's unincorporated footprint is small (roughly 2% of county land area) because the great majority of Cook is incorporated by Chicago and 134 suburban municipalities. Chicago's own ADU pilot ordinance (Chicago Municipal Code Sec. 17-9-0102) governs ADUs inside city limits in five designated pilot areas, which is where the bulk of Cook County ADU activity occurs. Suburban Cook municipalities (Evanston, Oak Park, Cicero, Schaumburg, Arlington Heights, Skokie, etc.) each set their own ADU rules under home-rule authority. Cook County's county-level ordinance is meaningful chiefly for the unincorporated pockets along the western and southern county boundaries.
State-floor overlay: Illinois has not enacted a statewide ADU preemption statute. Cook County and its 135 incorporated municipalities (Chicago plus 134 suburban) retain home-rule authority over ADU zoning. Illinois Constitution Art. VII grants home-rule powers to municipalities of population greater than 25,000.
County regulatory overlays
Cook County administers flood-hazard, and (where mapped) coastal, wildland-fire, historic, and airport overlays that shape ADU project feasibility. The most consistent overlay across the county is FEMA NFIP floodplain regulation; other overlays apply to specific geographies inside the county.
- FEMA NFIP Special Flood Hazard Areas in Cook County — A new ADU in a mapped SFHA must be elevated to or above the Base Flood Elevation; cost impact on the project is often material.
- Historic districts and individually-listed historic resources
County permitting (unincorporated parcels)
Cook County issues building permits for parcels in unincorporated territory through its development services / planning department, with separate review tracks for zoning conformance, building-code compliance, on-site sewage where applicable, floodplain compliance, and addressing. Inside incorporated municipalities, city departments handle their own permits; the county's authority is geographically limited to unincorporated territory. An ADU permit application is typically processed as a residential building permit with a zoning verification step against the county's ordinance for the parcel's zoning district.
Illinois state — ADU law and programs
State financing programs
Illinois does not operate an ADU-specific statewide loan, grant, or forgivable-loan program. The Illinois Housing Development Authority (IHDA) is the state's housing finance agency and administers a robust portfolio of homebuyer products: Access Forgivable, Access Deferred, Access Repayable down-payment-assistance variants, the IHDA Mortgage first-mortgage product, and the federal Low-Income Housing Tax Credit allocation. The 2025 IHDA Access Home program offers DPA equal to 6% of purchase price up to $15,000. None target ADU construction directly; an ADU-bearing primary residence on an Illinois lot can qualify for the underlying mortgage when other criteria are met.
Federal (United States) — ADU-relevant rules and programs
Federal ADU law
The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.
Federal financing programs
Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.
Federal tax credits
There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.
Federal housing programs
HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.
ZIP Codes
- 60601
- 60602
- 60603
- 60604
- 60605
- 60606
- 60607
- 60608
- 60609
- 60610
- 60611
- 60612
- 60613
- 60614
- 60615
- 60616
- 60617
- 60618
- 60619
- 60620
- 60621
- 60622
- 60623
- 60624
- 60625
- 60626
- 60628
- 60629
- 60630
- 60631
- 60632
- 60633
- 60634
- 60636
- 60637
- 60638
- 60639
- 60640
- 60641
- 60642
- 60643
- 60644
- 60645
- 60646
- 60647
- 60649
- 60651
- 60652
- 60653
- 60654
- 60655
- 60657
- 60659
- 60660
- 60661
- 60803
Post Office
- 10238 S Vincennes Ave, 60643
- 10422 S Ewing Ave, 60617
- 11033 S State St, 60628
- 116 S Western Ave, 60612
- 13234 S Baltimore Ave, 60633
- 1343 W Irving Park Rd, 60613
- 1419 W Carroll Ave Ste 1, 60607
- 1510 E 55th St, 60615
- 1704 N Milwaukee Ave Ste D, 60647
- 1723 W Devon Ave, 60660
- 1805 W Monterey Ave, 60643
- 1859 S Ashland Ave, 60608
- 2011 W Montrose Ave, 60618
- 2035 S State St, 60616
- 2302 S Pulaski Rd, 60623
- 2339 N California Ave, 60647
- 2345 S Wentworth Ave Ste A, 60616
- 2405 N Sheffield Ave, 60614
- 2522 W Lawrence Ave, 60625
- 2643 N Clark St, 60614
- 3024 N Ashland Ave, 60657
- 324 S Laramie Ave, 60644
- 3319 N Cicero Ave, 60641
- 3349 W 111th St, 60655
- 3401 W Devon Ave, 60659
- 355 E Ohio St Ste 200, 60611
- 3635 N Lincoln Ave, 60657
- 3638 W 111th St, 60655
- 3639 W 79th St, 60652
- 3750 N Kedzie Ave, 60618
- 4222 W Madison St, 60624
- 4301 W 69th St, 60629
- 433 W Harrison St Fl 3e, 60699
- 433 W Harrison St Fl 3w, 60699
- 4601 S Cottage Grove Ave, 60653
- 4642 S Bishop St, 60609
- 4749 N Bernard St, 60625
- 4810 N Milwaukee Ave, 60630
- 4850 N Broadway St, 60640
- 4922 S Kedzie Ave, 60632
- 5001 W Division St, 60651
- 5100 W Grand Ave, 60639
- 540 N Dearborn St, 60610
- 5401 W Lawrence Ave, 60630
- 5424 W Devon Ave, 60646
- 5645 S Archer Ave, 60638
- 6037 S Kedzie Ave, 60629
- 611 W 63rd St, 60621
- 6300 N Northwest Hwy, 60631
- 6441 W Irving Park Rd, 60634
- 6559 S Ashland Ave, 60636
- 700 E 61st St, 60637
- 7436 S Exchange Ave, 60649
- 7601 S Cicero Ave Ste 808, 60652
- 7617 N Paulina St, 60626
- 7715 S Cottage Grove Ave Ste 1, 60619
- 7748 S Cottage Grove Ave, 60619
- 8345 S Ashland Ave, 60620
- 9308 S South Chicago Ave, 60617
Locale Names
- Ashburn
- Auburn Park
- Charles A Hayes
- Chicago Cent Carrier Annex
- Chicago Lawn
- Chinatown
- Clearing
- Cragin
- Daniel J Doffyn
- Detached Po Box 60622
- Detached Po Box 60647-2
- Detached Po Box 60652
- Detached Po Box 60655
- Edgebrook
- Elsdon
- Englewood
- Finance Station H
- Finance Station L
- Finance Station M
- Finance Station Q
- Finance Station T
- Finance Station W
- Fort Dearborn
- Graceland
- Graceland Carrier Annex
- Grand Crossing
- Grand Crossing C Annex
- Hegewisch
- Henry W McGee
- Irving Park
- Jackson Park
- Jefferson Park
- Jefferson Park Carrier Annex
- John Buchanan
- Lake Park
- Lakeview
- Lincoln Park Carrier Annex
- Lincoln Park Postal Store
- Loop Carrier Annex
- Mary Alice Henry
- Morgan Park
- Mount Greenwood
- Nancy B Jefferson
- Northtown
- Norwood Park
- Ogden Park
- Otis Grant Collins
- Pilsen
- Ravenswood
- Rev Milton R Brunson
- Robert Leflore Jr
- Roberto Clemente
- Roger P McAuliffe
- Rogers Park
- Roseland
- Southwest Carrier Annex
- Stockyard Carriers
- Streeterville
- Twenty Second Street
- Uptown
- Wicker Park Carrier Annex