Plumbing Contractor License Requirements in Illinois

Overview — plumbing licensing in Illinois

Illinois requires a state-level plumbing contractor license, issued by the Illinois Department of Public Health (IDPH), Plumbing Program. The license verifies competence and consumer protection, and is required to legally bid and perform plumbing work in the state. Working without one when required is typically a misdemeanor and exposes the contractor to civil penalties — and the contract becomes unenforceable in court.

License classes available

Illinois offers 2 plumbing license classes — pick based on the largest project you plan to bid:

• Plumbing License (Plumber). State plumbing license. Single classification covering all plumbing work.
• Plumbing Contractor License. Business license. Must employ at least one licensed plumber.

Experience required

4 years apprentice (8,000 hours) registered with IDPH-approved apprenticeship.

Exam — what you're tested on

Illinois requires a written examination administered by IDPH-administered. Topics covered:

• IL Plumbing Code
• Calculations
• Public health rules

Passing score: 70%.

Fees

• Application fee: $200
• Initial license fee: $100
• Renewal fee: $100 ( annual)

Bond & insurance

Bond: Not required at the state level. IL doesn't require state bond but Chicago does ($10,000).

General liability insurance: Minimum $250,000.

Workers' compensation: Required for any IL employer.

Continuing education

Illinois requires 4 hours of continuing education annual. CE must come from approved providers — verify a course is approved before paying. Required topics typically include:

• IL Plumbing Code updates

Reciprocity with other states

Illinois does not have formal plumbing reciprocity with other states. Out-of-state contractors must complete the Illinois process from scratch.

Local permits and requirements

Chicago requires city plumbing license on top of state. Suburbs and downstate require permits but typically accept state license.

Common gotchas

Things that catch most applicants on their first license cycle in Illinois:

• Apprentice must register with an IDPH-approved program — informal training doesn't count.
• Annual renewal vs biennial in many states.
• Chicago has its own plumbing license + inspection regime on top of IDPH.
• Illinois Plumbing Code differs from IPC — exam tests IL-specific rules.

Frequently asked questions

Does Illinois have separate residential and commercial plumbing licenses?

No — single state plumbing license covers both. Project complexity varies but the license scope is uniform.

How long does Illinois plumbing licensing take?

4-year apprenticeship → exam → license issued in 8–14 weeks total. Total career timeline: 4–5 years.

Why does Illinois have its own plumbing code?

Illinois adopted its own plumbing code based on early 20th century public health rules. Periodically harmonized with IPC but retains specific provisions for water quality, lead-free piping, and venting.

Do I need a Chicago plumbing license too?

Yes if you plumb in Chicago. Chicago requires its own master plumber license + city contractor registration on top of the IDPH state license.

What's IL's annual plumbing CE requirement?

4 hours per year, IDPH-approved providers. Less than many states but strictly enforced — failure to complete = automatic license suspension.