Illinois (IL) Plumbing Code & Permit Rules
Illinois Plumbing Code (IPC-based with heavy amendments) (2014) · Updated 2026-05-31
Data: State plumbing boards, ICC, IAPMO, EPA Last verified: 2026-05-31
Illinois requires licensed plumbers for most plumbing work and mandates annual backflow testing. These regulations help protect water quality but mean higher costs for homeowners compared to states that allow DIY work.
Plumbing Code
Illinois follows the Illinois Plumbing Code (IPC-based with heavy amendments) (2014 edition).
Based on IPC but heavily amended; not a straight IPC adoption
Key Regulations
| Regulation | Status | Details |
|---|---|---|
| Plumbing Code | State-specific (2014) | Illinois Plumbing Code (IPC-based with heavy amendments) |
| Homeowner DIY | Not allowed | Licensed plumber required for all plumbing work |
| Water Heater Permit | Required | Licensed plumber required for all plumbing work |
| Backflow Testing | Annual, required | Statewide mandate; covers irrigation and commercial |
| Seismic Strapping | Not required | Water heater restraint |
DIY Plumbing in Illinois
Illinois requires a licensed plumber for most plumbing work. Licensed plumber required for all plumbing work
While this increases costs, it ensures:
- Work meets current code requirements
- Proper permitting and inspection
- Warranty and liability protection
- Safe connections to water and sewer systems
Backflow Prevention
Illinois requires annual backflow testing to protect the public water supply from contamination. Testing must be performed by a Licensed plumber.
Non-compliance penalty: Water service may be shut off if testing is not completed on schedule.
Water Conservation Requirements
Illinois follows federal water conservation standards. Federal minimums apply
Lead Service Line Replacement
Illinois has an active lead service line replacement program. Massive lead service line replacement program (Chicago); aggressive state mandate
Data Sources
- Illinois state plumbing board and licensing agency
- International Code Council (ICC)
- IAPMO
- EPA Safe Drinking Water Act
Updated as regulations change.
Need a licensed plumber in Illinois?
Plumbing regulations vary by city. Connect with a licensed professional who knows your local code requirements.
Find a Licensed Plumber →Frequently Asked Questions
What plumbing code does Illinois follow?
Illinois follows the Illinois Plumbing Code (IPC-based with heavy amendments) (2014 edition).
Can I do my own plumbing work in Illinois?
No, Illinois requires a licensed plumber for most plumbing work.
Do I need a permit to replace a water heater in Illinois?
Yes, Illinois requires a permit for water heater replacement. A licensed plumber is required for the installation.
Is backflow testing required in Illinois?
Yes, Illinois requires annual backflow testing.
Does Illinois require seismic strapping for water heaters?
No, Illinois does not require seismic strapping for water heaters. However, they remain a prudent option in areas with seismic activity.