Plumber license requirements in Illinois.
Illinois licenses plumbers at the state level through the Illinois Department of Public Health. Anyone who installs, alters, extends, repairs, or maintains plumbing must be licensed, and the standard route is a registered apprenticeship under a licensed plumber followed by the state licensing exam.
What Illinois requires.
Licensed Plumber
The state license to plan, install, alter, extend, repair, and maintain plumbing systems in Illinois.
Licensed Apprentice Plumber
Registers with IDPH and works under a licensed plumber while accumulating the required experience. The apprenticeship period is capped — after it runs out you must sit for the license exam to keep renewing.
Getting the Licensed Plumber
- Serve as a licensed apprentice plumber under a licensed plumber for the required period (roughly four years, with a six-year cap on the apprenticeship)
- Meet IDPH’s education requirement — at least two years of high school or the equivalent, plus approved course instruction
- Pass the state plumber licensing exam
Renewal: Plumber licenses renew annually by April 30, with continuing education from IDPH-approved course sponsors.
- · Published figures for the annual continuing-education hour requirement vary between sources — confirm the current number directly with IDPH before you renew.
- · Chicago plumbing work also involves the city’s own code and permitting requirements on top of the state license.
Verified 2026-08 against the sources below. Licensing rules change — confirm with the board before relying on this page.
Illinois plumbing licensing FAQ.
Do you need a license to do plumbing work in Illinois?
Yes. Illinois requires a state plumbing license from the Illinois Department of Public Health for anyone who plans, installs, alters, extends, repairs, or maintains plumbing. Apprentices must also be licensed and work under a licensed plumber.
Who issues plumbing licenses in Illinois?
The Illinois Department of Public Health (IDPH) runs the state plumbing program — it licenses plumbers and apprentices, approves continuing-education sponsors, and handles renewals.
How long is a plumbing apprenticeship in Illinois?
The standard path is roughly four years as a licensed apprentice plumber working under a licensed plumber, and the apprenticeship is capped at six years — once you hit the cap you have to sit for the licensing exam to keep renewing.
When do Illinois plumbing licenses renew?
Annually, by April 30. Renewal requires continuing education taken from IDPH-approved sponsors; confirm the current hour requirement with IDPH, since published figures vary.
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