Permit timelines are usually answered with a shrug, or with a number from a city web page that nobody measures against reality. This is what Chicago's own permit records actually show: the time between the date a permit was filed and the date it was issued, across 23,541 Chicago permits that carry both dates.
The short answer: the median Chicago building permit is issued 6 days after it is filed. Half are issued sooner. The middle half land between 0 and 28 days, and the type of work moves that number more than anything else — see the table below.
How long it actually takes
This guide reflects actual processing times recorded by Chicago’s building department, measured from the date a permit was filed to the date it was issued. It is based on real issued permits, not any published city targets or promises. The median value represents the most reliable expectation for typical cases, but the range of actual processing times is more important than the midpoint itself.
The spread between the fastest and slowest permits matters significantly. A permit might clear in a few days or take weeks, depending on the specific circumstances of the project. Relying solely on the median can mislead; understanding the typical range for your type of work is essential for realistic planning.
What the numbers say
The table below displays median processing times for common permit types based on Chicago’s own records. It reveals that straightforward trades like fencing or minor electrical work typically clear much faster than complex projects involving structural changes or new construction.
| Type of work | Median days to issue | Typical range | Permits measured |
|---|---|---|---|
| Plumbing | 9 | 3–41 | 2,458 |
| Deck / patio | 42 | 10–101 | 1,861 |
| Solar / PV | 11 | 7–16 | 1,166 |
| New home | 52 | 12–118 | 1,127 |
| Fence | 3 | 0–41 | 984 |
| Reroofing | 1 | 0–6 | 896 |
| Demolition | 13 | 0–56 | 896 |
| Fire / sprinkler | 2 | 1–7 | 879 |
| Windows | 15 | 2–68 | 533 |
| Addition | 103 | 55–166 | 512 |
| HVAC | 34 | 8–77 | 484 |
| Electrical service upgrade | 0 | 0–5 | 390 |
Simple trades such as fencing or electrical work generally move quickly through the system, while projects requiring detailed engineering reviews, like new homes or large deck installations, face longer waits. The nature of the work—whether it involves standard plans or unique structural requirements—drives the difference in processing speed.
What actually drives your timeline
- Incomplete applications require resubmission, adding days to the timeline.
- Permits needing formal plan review take longer than those issued over-the-counter.
- Revisions and resubmittals after initial review significantly extend processing.
- Unplanned scope changes during the application phase delay final approval.
- Seasonal workloads and departmental backlogs create natural fluctuations in speed.
How to use this
Compare your project type to the permits already issued for similar work in Chicago. This gives you a realistic baseline for when you might expect your permit to clear, based on actual historical data.
If your application hasn’t moved after a period typical for your permit type, it may be stalled. Use the table to identify whether your timeline is normal or if further action is needed with the department.
Check your own project
Look up what comparable permits actually cost and how long they took with the free permit benchmark check — pick Chicago, your type of work, and your budget.
- Chicago building permits: search and history — recent filings with addresses, types, and valuations.
- Look up a specific address — see what has been filed at a property.
- Weekly Chicago permit digest — the biggest projects filed each week.
Timelines are measured from The Permit Sheet's copy of Chicago's official permit records and reflect permits that were actually issued. They are a description of what happened, not a promise about your application.