Illinois Building Permits — Complete Guide (2026)
Find, Apply & Track Permits in Cities and Counties Across Illinois
Illinois permitting is dominated by the Chicago metro, which has its own unique building code and permitting system. Suburban Cook County and downstate Illinois have significantly simpler, faster requirements.
How building permits work in Illinois
Building permit requirements and processing times in Illinois vary by city and county. Use the links below to apply, check status, schedule inspections and find permit information for your location.
Learn the step-by-step permit process →Not sure where to apply?
Enter your city or address to find your permit office.
Permit costs by type — Illinois
| Permit Type | Fee Range | Processing Time | Notes |
|---|---|---|---|
| Electrical | $120–$350 | 2–7 days | Chicago: licensed electrician must pull permit |
| Plumbing | $100–$300 | 2–7 days | Chicago: licensed plumber required |
| HVAC / Mechanical | $120–$350 | 2–7 days | Chicago: licensed mechanical contractor |
| Roofing | $150–$450 | 2–7 days | Chicago: licensed roofing contractor required |
| Room Addition | $500–$1,500 | 4–10 weeks | Chicago: architect required for most additions |
| New Construction | $1,000–$3,500 | 4–12 weeks | Chicago: extensive plan review process |
| Garage Conversion | $300–$800 | 2–6 weeks | Suburban IL — simpler process |
| Deck / Patio | $150–$500 | 2–5 weeks | Frost-line footings required (42 inches) |
| Fence | $75–$200 | 1–5 days | HOA rules common in suburban IL |
| Solar | $120–$350 | 2–7 days | Illinois Future Energy Jobs Act supports solar |
Major Illinois cities — apply online
Most Illinois building permits are issued by cities. Click your city to access the permit portal, apply online, or check permit status.
Permit costs by county — top Illinois counties
County building departments handle unincorporated areas. Click a county to access its permit portal directly.
How to get a building permit in Illinois
Determine Chicago vs. suburban or downstate process
If you are in Chicago city limits, all permits go through the City of Chicago Department of Buildings. The process differs significantly from suburban Cook County, DuPage, Lake, and other collar counties.
Chicago: access the city permit portal
Chicago's permit portal handles most applications. Simple work permits can be obtained online. Complex projects require a licensed design professional to file.
Chicago: understand trade license requirements
Chicago requires licensed contractors to pull permits for all electrical, plumbing, HVAC, and roofing work. Homeowners cannot self-perform permitted trade work in Chicago.
Suburban and downstate: contact your local building department
Outside Chicago, permits are handled by city or village building departments. Many suburbs have streamlined systems with shorter timelines and lower fees than Chicago.
Inspections
Chicago has a dedicated inspection division with online scheduling. Wait times can be significant during busy seasons. Suburban municipalities generally have faster turnaround.
ADU permits in Illinois — what you need to know
🏠 Illinois ADU-friendly status: No — Chicago is restrictive
Illinois has no statewide ADU law. Chicago passed ADU ordinances in 2020 allowing coach houses and basement apartments in 5 pilot zones, expanding citywide in 2023. Suburbs vary widely — many have restrictive zoning that effectively prohibits ADUs.
Find a licensed Illinois contractor
Illinois requires licensed professionals for most permitted work. Always verify a contractor's license before hiring — it protects you and is required for most permit types.
General Contractors
Find pre-screened general contractors for your Illinois home project. Compare quotes on permitted work.
Find a Contractor →Verify IL License
Verify your contractor holds a valid Illinois Department of Financial & Professional Regulation (IDFPR) license before any permitted work begins.
Verify IL License →Electricians & Plumbers
Specialty-licensed electricians and plumbers are required for all permitted electrical and plumbing work in Illinois.
Learn More →Ready to get started? Browse verified, licensed contractors serving Illinois homeowners and get free quotes on your project.
🔍 Find a Contractor Near YouFrequently asked questions — Illinois permits
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