Illinois is one of the few states that licenses plumbers statewide, through IDPH, with a single Plumber license and no journeyman/master split. Here's the 2026 apprenticeship, exam, fees, contractor registration, and the Chicago exception.
Illinois does something most states don't: it licenses plumbers at the state level. While Illinois leaves general contractors and electricians to be licensed city by city, plumbing is regulated statewide by the Illinois Department of Public Health (IDPH) under the Illinois Plumbing License Law (225 ILCS 320). That makes the plumbing path in Illinois clearer than the patchwork most trades face here, but it comes with its own quirks, including a single plumber license (no journeyman/master split) and a big exception for Chicago.
This guide walks the full path: apprentice, the licensed plumber exam and requirements, the fees, the Chicago carve-out, and how the license connects to the plumbing contractor registration a business needs to actually take work. It covers the licensing process only, not exam preparation.
The Illinois plumbing credentials
Under the Illinois Plumbing License Law, IDPH issues a handful of plumbing-related credentials:
- Apprentice Plumber, the entry point; works under a licensed plumber.
- Plumber, the licensed plumber credential. This is the key one, and Illinois has only one tier. There is no separate "journeyman" and "master" plumber in the state system the way most states run it. Once you're a licensed Plumber, you're a licensed Plumber.
- Plumbing Contractor, a registration (not a personal skill license) for anyone doing plumbing work for another person; this is the business layer.
- Irrigation Contractor and Retired Plumber, narrower categories.
The one-license structure is a genuine difference from states like Texas, Michigan, or Georgia, where you climb from journeyman to master. In Illinois, the ladder is simply apprentice → licensed Plumber. If you're used to the two-tier model, our national explainer on journeyman vs. master plumber is useful context for why Illinois is the exception.
The big exception: Chicago
Before anything else, know this: Chicago runs its own plumbing licensing system. Work performed exclusively within Chicago city limits falls under the City of Chicago Department of Buildings, a home-rule authority that sets its own examination and registration rules separate from IDPH. Outside Chicago, the IDPH state plumbing license governs statewide.
Practically, most plumbers who want to work across Illinois pursue the IDPH license, and those focused solely on Chicago deal with the city. This guide covers the IDPH state path.
Step 1, Apprentice plumber
The Illinois plumbing path starts as a registered apprentice:
- Minimum age 16.
- Sponsorship by an Illinois licensed plumber or an approved apprenticeship program.
- Complete the apprentice plumber application with IDPH.
The apprenticeship is where you log the hours. Illinois sets the term at not less than 1,400 hours per year, for a total of 5,600 hours over four years. There's an alternate route as well: serve at least two years as a licensed apprentice plumber plus complete two years of approved plumbing coursework, reaching the same 5,600-hour benchmark through combined work and schooling.
Step 2, Licensed plumber
Once the apprenticeship is complete, you apply to sit for the plumber's examination. IDPH's stated requirements include:
- Employment as a licensed apprentice plumber for a minimum of four years;
- Completion of at least two years of high school or the equivalent; and
- Completion of approved course instruction through a college, university, or trade school.
You file the Plumber's License: Application for Examination at least 30 days before the exam date and pay the fee. The exam tests plumbing system planning and design, practical plumbing knowledge and skills, and knowledge of the Illinois Plumbing Code.
Fees are set by IDPH and change, verify current amounts before applying. As a reference point, the plumber license examination fee has been $175 for in-state applicants and $225 for Chicago and out-of-state applicants. Confirm the current figure with IDPH before you file.
We cover the licensing process here, not how to study, Illinois expects you to know the Illinois Plumbing Code cold, but exam preparation is outside this guide.
Step 3, The plumbing contractor registration (the business layer)
Holding a licensed Plumber credential lets you do plumbing work. But if plumbing work is being done for another person, i.e., you're running a plumbing business, Illinois requires a separate Plumbing Contractor registration with IDPH. This is the layer that matters when your company signs contracts and pulls permits, and it's the one with real financial requirements.
To register as a plumbing contractor, IDPH generally requires:
- A licensed plumber tied to the business. A plumbing contractor is a licensed plumber (or licensed apprentice) performing work for others, a licensed plumber has to stand behind the operation.
- A $20,000 surety bond (or an equivalent letter of credit). Note the Illinois quirk: the bond cannot be continuous, it must expire September 30 of the current year and be renewed.
- Certificate of insurance with per-occurrence coverage of $100,000 general liability, $300,000 bodily injury, $50,000 property damage, and $500,000 workers' compensation. The certificate must stay in force at all times for the registration to remain valid.
- The annual registration fee, which has been $150 per year (non-refundable). Verify the current fee with IDPH.
This business-registration step is where the same structural question comes up that we see in every state: what if the person who owns and runs the plumbing business isn't a licensed plumber? Illinois requires a licensed plumber behind the contractor registration. If the owner doesn't hold that license, the business needs one who does. For how the business registration sits against your personal license generally, see contractor license vs. business license.
What it costs (and how long it takes)
The honest answer on cost is that the state fees are the small part. The exam application (in the range of $175), the annual plumbing contractor registration (around $150), the $20,000 bond premium, and insurance are the published pieces, verify each with IDPH and your bond/insurance provider, since the state sets the fees and premiums vary by carrier.
The time is the real cost: a four-year apprenticeship (5,600 hours) plus the coursework and exam. There is no shortcut around the hours for an individual license, Illinois wants the experience. That long runway is exactly why many businesses that need to operate now look at bringing an already-licensed plumber into the company rather than waiting years to grow one. We break down the timeline question generally in how long does it take to get a contractor license?.
The faster path for a business: a qualifying plumber on your team
If you're an individual, there's no way around the apprenticeship, put in the hours and take the exam. But if you're a business that needs to be able to contract for plumbing work and your owner isn't a licensed Illinois plumber, the practical route is different: bring a licensed plumber into the company to satisfy the requirement.
The legal way to do that is as a genuine W-2 employee, which is exactly what a qualifying agent is. A qualifying agent is a properly licensed professional employed by your firm who serves as the licensed individual the state requires standing behind your plumbing work.
Be careful here, because the illegal version of this is common and increasingly prosecuted: license lending, paying for someone's license to appear on your business while they do no real work, is prohibited, and states are tightening enforcement (Georgia, for example, rewrote its licensing law in 2026 to add explicit discipline for lending, leasing, or renting a license). The difference between the illegal arrangement and the legal one is a real employment relationship. We lay out that line in is it legal to rent a contractor license?.
A qualifying agent is on your payroll as a full-time W-2 employee, not a percentage of the job, not a per-permit fee, not a 1099 handshake, not a name on a form. That's what makes the arrangement defensible. Read the full explanation in what is a qualifying agent and the plumbing-specific version in plumbing contractor qualifying agent.
The Licensing Company places licensed plumbers and other qualifying professionals as full-time W-2 employees to fill the exact credential a business is missing, structured to your situation, scope, and risk. Bring one on at hire a qualifying agent, or scope your situation at consultation packages.
Frequently asked questions
Does Illinois have a state plumbing license? Yes, and it's one of the few trades Illinois licenses statewide. Plumbing is regulated by the Illinois Department of Public Health under 225 ILCS 320. (Most other trades, including general contractors and electricians, are licensed locally in Illinois.) The exception is Chicago, which runs its own plumbing licensing.
Is there a journeyman and master plumber license in Illinois? No. Illinois has a single licensed Plumber credential, there's no separate journeyman/master split at the state level, unlike most states.
How long does it take to become a licensed plumber in Illinois? Plan on about four years as a registered apprentice (roughly 1,400 hours a year, 5,600 hours total), plus the required coursework, before you can sit for the state exam. There's no shortcut on the hours for an individual license.
How much does an Illinois plumbing license cost? The exam application fee has been around $175 in-state ($225 for Chicago/out-of-state), and the annual plumbing contractor registration around $150, but IDPH sets these amounts and they change, so verify before applying. A registered plumbing contractor also needs a $20,000 bond and specific insurance, whose premiums vary by provider. We don't publish placement pricing for qualifying agents because it depends on your situation; scope it at consultation packages.
Can a company hold an Illinois plumbing contractor registration without a licensed plumber? No, a licensed plumber has to stand behind the plumbing contractor registration. If the business owner isn't a licensed Illinois plumber, the company brings one on. Done legally, that's a W-2 qualifying-agent placement, not a rented license.
Do I need an IDPH license to plumb in Chicago? Chicago runs its own home-rule plumbing licensing through the Department of Buildings. Work performed exclusively within the city falls under Chicago's system; the IDPH state license governs the rest of Illinois. Verify which applies to where you'll actually be working.
This guide covers the Illinois plumbing licensing process and is current as of 2026. Fees, bond and insurance minimums, and requirements are set by IDPH, the City of Chicago, and by statute (225 ILCS 320) and can change, always verify current requirements with the state before applying. This is not exam-preparation material. The Licensing Company places qualifying professionals as full-time W-2 employees; it does not lend, rent, or lease licenses.
Disclaimer: This article is provided for educational and informational purposes only. It does not constitute legal advice, licensing guidance, or an offer of services. Licensing requirements vary by jurisdiction. For specific compliance questions, contact The Licensing Company for a confidential consultation.