How Do You Get a Plumbing License in Illinois?

Yes.

Illinois licenses plumbing statewide through the Illinois Department of Public Health (IDPH) under the Illinois Plumbing License Law (225 ILCS 320).

All planning, designing and performing of plumbing must be done by plumbers licensed under the Act or by licensed apprentice plumbers; the exemption is a homeowner working on their own single-family residence.

IDPH's plumbing page says it licenses about 8,900 plumbers and about 2,000 apprentice plumbers.

Illinois has two individual license levels, and no journeyman or master tiers: licensed apprentice plumber and licensed plumber.

An apprentice must be at least 16 and sponsored by an Illinois licensed plumber or an approved apprenticeship program, and may not accumulate more than 6 years as an apprentice.

The licensed plumber is the full license the Act requires in order to do plumbing, and a licensed plumber may sponsor or supervise no more than 2 apprentices at once — if 2, one must have at least 2 years as a licensed apprentice.

IDPH's list also includes a retired plumber license plus plumbing contractor and irrigation contractor registrations; the contractor registration is the business layer, held by anyone performing plumbing for another person.

Cities of 500,000 or more — in practice, Chicago — may run their own board of plumbing examiners under an ordinance substantially the same as the state Act, and Chicago accepts plumbers or apprentices licensed by either the city or the state as employees of a Chicago-licensed plumbing contractor.

The entry rung is the apprentice license: be at least 16, and be sponsored by an Illinois licensed plumber or an approved apprenticeship program.

If a sponsor ends the sponsorship, IDPH must be notified within 15 days.

To sit the plumber exam, you need at least 2 years of high school (or equivalent) and at least 4 years as an Illinois licensed apprentice plumber under supervision, or completion of an approved plumbing course supervised by an Illinois licensed plumber, and you must apply at least 30 days before the exam.

The plumbing contractor registration requires the plumbing license of the sole proprietor, a partner, or a corporate officer, and every employee doing plumbing must be a licensed plumber or apprentice.

Our research did not confirm IDPH's application, exam or license fees — ask IDPH before you apply.

IDPH itself holds the examinations: the Act requires the Department to hold exams for plumber license applicants at least once every three months, and you must file your application at least 30 days before the exam date.

Our research does not describe what the exam covers or name a testing vendor — IDPH's plumbing program page is the place to confirm the current schedule, format and study material.

Plumber licenses renew annually: IDPH says they must be renewed by April 30 following the date of issuance, through its online renewal page.

Each licensed plumber must, as a condition of each annual renewal after the first license, provide proof of completion of 4 hours of continuing education.

Plumbing contractor registrations are on a different cycle — they expire on the last day of September each year.

Our research did not find a reciprocity provision in the Illinois Plumbing License Law (225 ILCS 320).

That is an absence in our research, not a confirmed no: Illinois may still recognize out-of-state licenses in cases we did not find.

If you hold a plumber license from another state, ask IDPH directly whether any recognition or waiver applies before you assume you must repeat Illinois's apprentice years.

IDPH licenses plumbers statewide, and its plumbing program page is the official source for license information; our research did not capture a separate public IDPH license-lookup URL, so start there and follow its license links.

If you cannot find a license record, confirm it with IDPH directly.