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Illinois Master Plumber License (IDFPR)

Illinois Department of Financial and Professional Regulation issues the state's only state-level construction-trade license: Master Plumber and Apprentice/Journeyman Plumber under the Illinois Plumbing License Law (225 ILCS 320). Illinois has no state GC license — Chicago BACP and other municipalities handle GC registration.

Established 1935·Official site →·Verify →

Illinois Master Plumber License (IDFPR) — Definitive Guide 2026

The Illinois Department of Financial and Professional Regulation (IDFPR) administers the state's only state-level construction-trade license: Master Plumber and Apprentice/Journeyman Plumber under the Illinois Plumbing License Law (225 ILCS 320) and the Illinois Plumbing Code (77 Ill. Adm. Code 890). Illinois has no state-level general contractor license — that role is handled by municipal registration (Chicago Buildings, Aurora, Naperville, etc.). Roofing is the only other state-level construction credential, issued under the Illinois Roofing Industry Licensing Act (225 ILCS 335).

What it governs

The Plumbing License Law has three credential tiers: Apprentice Plumber, Journeyman Plumber, and Master Plumber. Apprentices register with IDFPR and work under direct Master supervision. Journeyman Plumbers pass a state journeyman exam after a four-year apprenticeship and may perform plumbing work under a Master's license. Master Plumbers pass a state Master examination and may pull plumbing permits and supervise crews.

The Master Plumber license is required for any contractor engaging in the business of plumbing in Illinois. The licensee must be a licensed Master, and the Master may operate as a sole proprietor or qualify a corporation/LLC. Continuing education is 4 hours per year. The license number is a 7-digit integer prefixed by trade-class (058 for Master Plumber, 159 for Plumbing Contractor business license).

The Plumbing Contractor business license is a parallel credential — held by the business entity rather than the individual — and authorizes the business to bid plumbing work. A Plumbing Contractor must employ at least one Master Plumber as a qualified individual. Bond and insurance minimums apply: $20,000 surety bond plus liability insurance per the Plumbing Contractor License Act (225 ILCS 320 § 25).

Homeowner implications

For an Illinois homeowner, plumbing work performed by an unlicensed individual is non-compliant and may not be permitted. Licensed plumbers are mandatory for new water-supply, drain-waste-vent, and gas-piping installations. Minor self-help (replacing a faucet, replacing a toilet trim) generally falls outside the licensure trigger, but anything affecting the supply, drainage, or gas systems requires a licensed Master to pull the permit.

Verification: search the IDFPR public lookup by license number or business name. Confirm: license type (Master Plumber 058, Plumbing Contractor 159), status (Active, Expired, Suspended), expiration date, and any open disciplinary action. Cross-reference the Plumbing Contractor business license on file with the City of Chicago (or other municipal) plumbing-permit roster — Chicago requires both state and city licensing for permit issuance.

For Chicago projects specifically, a Department of Buildings Plumbing Permit is required in addition to the state license. Cook County and the City of Chicago use the IPC (Illinois Plumbing Code) plus city amendments — non-Chicago municipalities follow the IPC directly.

Contractor implications

A plumbing contractor in Illinois operates two licenses simultaneously: the individual Master Plumber license (held by an individual person) and the Plumbing Contractor business license (held by the business entity). The same person can hold both, but the business cannot bid plumbing work without an employed Master. The business license requires a $20,000 surety bond plus liability insurance per the Plumbing Contractor License Act.

GC contractors in Illinois who do not perform plumbing work themselves must subcontract to a Plumbing Contractor for any plumbing scope. The state explicitly prohibits a GC's employee — even if individually licensed — from working plumbing scope under the GC's business when the GC entity does not hold a Plumbing Contractor business license. This is a frequent compliance failure.

How AskBaily uses it

Every AskBaily homeowner-to-GC match for an Illinois project that includes plumbing scope runs:

Recent changes 2024–2026

The 2024 IDFPR rule update tightened continuing-education documentation requirements and introduced a digital-credential portal for Master Plumber renewal. The 2025 Illinois Plumbing Code amendments aligned more tightly with the 2018 IPC base text plus state-specific amendments for cross-connection control.

The 2024 Illinois legislative session considered (but did not pass) a state-level General Contractor licensing bill — the bill has been revived multiple times since 2018 without successful passage. As of 2026, Illinois remains a municipal-licensing state for GCs.

Frequently asked questions

Does Illinois license general contractors? No. Only roofing and plumbing are licensed at the state level. GCs are licensed at the city level — Chicago BACP, Aurora, Naperville, Elgin, etc.

Can my plumber work in any city in Illinois? The state license is statewide. Chicago and a few other large cities require additional city-level plumbing-permit-eligibility, but the underlying state license is universal.

What's the difference between Apprentice, Journeyman, and Master Plumber? Apprentices work under direct supervision. Journeyman work under the supervision of a Master. Only Master Plumbers can pull permits and supervise.

Where do I verify an Illinois plumbing license? The IDFPR online lookup at ilesonline.idfpr.illinois.gov/DPR/Lookup/LicenseLookup.aspx.

Does my homeowner insurance pay if my plumber was unlicensed? Most policies have an exclusion for unpermitted or unlicensed work. Confirm with your carrier.

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