How to Get a Plumbing License in Iowa: PMSB Steps, Fees and Timeline (2026)

Getting a plumbing license in Iowa means working through the Plumbing and Mechanical Systems Board (PMSB) ladder: a registered apprenticeship, the Kirkwood Community College journeyperson exam, two more years on the job, then the master exam. Iowa licenses the trade statewide under Iowa Code chapter 105, through the Department of Inspections, Appeals and Licensing (DIAL), and uses Kirkwood as its only exam vendor, not PSI, Prov or Pearson VUE.

At a glance

• Who issues it: the Plumbing and Mechanical Systems Board (PMSB) inside DIAL
• The exam: Kirkwood Community College, $35 exam approval application per discipline plus a $119 exam fee per attempt
• License fees: $50 apprentice, $180 journeyperson, $240 master, for a full three-year period
• To contract: $250 PMSB contractor license plus $150 DIAL registration ($400), plus $500,000 liability insurance and a $5,000 bond
• The time: about six years: four years of apprenticeship, the journey exam, two more years, then the master exam

How to Get a Plumbing License in Iowa

Iowa licenses plumbers at the state level only. Iowa Code chapter 105 put the credential in state hands, section 105.17 voided every local plumbing license on July 1, 2009, and the rules now live in 481 Iowa Administrative Code chapters 425 through 435 (moved from title 641 in April 2025; older guides still cite the dead chapter numbers). Iowa's plumbing code is the 2024 Uniform Plumbing Code (UPC), adopted with Iowa amendments at 481 IAC chapter 425, effective March 26, 2025; rule 425.2 bars cities from adopting any other plumbing code, though stricter local amendments are allowed. Permits and inspections stay local; the credential does not.

The Plumbing and Mechanical Systems Board (PMSB) licenses everyone who designs, installs, alters or repairs plumbing, mechanical, HVAC-refrigeration, sheet metal or hydronic systems in Iowa, and everyone who contracts for that work. There is no dollar threshold: the trigger is the scope of the work, not the size of the job (section 105.10). DIAL administers the board at 6200 Park Avenue, Suite 100, Des Moines, IA 50321; main line 866.280.1521.

If you are building a plumbing business rather than your own credential, start with our Iowa contractor license guide for the registration side, or our national contractor license overview if you work across more than one state.

Iowa's five trade disciplines, and why that shapes your path

Iowa does not issue one generic "plumbing license." It licenses by discipline (plumbing, mechanical, HVAC-refrigeration, sheet metal and hydronic), and every fee, exam and supervision rule attaches to the discipline, not the person. A master plumber cannot superintend HVAC work on that license alone.

Two shortcuts help on the mechanical side. A mechanical license covers HVAC-refrigeration, sheet metal and hydronic work in one credential (section 105.10(3)). And passing both the HVAC-refrigeration and hydronic exams at one level earns the mechanical license without a separate mechanical exam (section 105.18(2)).

Iowa plumbing license types, from apprentice to master

Three individual licenses form the ladder: apprentice, journeyperson and master. A fourth, the contractor license, lets a business hold a contract. Fees below are for a full three-year period; mid-period applications are prorated.

Notes:

• An inactive master held alongside an active journeyperson license in the same discipline costs $230 combined, not $240 plus $180.
• Inactive and specialty licenses (disconnect/reconnect, hearth systems, private school maintenance, HVAC service technician) are $50 for a full period.
• The medical gas system installer credential, which runs on NITC certification rather than the PMSB ladder, is $75.
• All fees are set by the board or Kirkwood and change; verify current numbers with DIAL and Kirkwood before relying on them.

See journeyman vs. master plumber for how the two credentials differ day to day.

Experience and education requirements for each license

Apprentice: at least 18 years old, a high school diploma or GED, documentation of any criminal convictions, certification that you work under a licensed journeyperson or master, and enrollment in an apprenticeship registered with the U.S. Department of Labor Office of Apprenticeship. One apprentice license covers all five disciplines.

Journeyperson: at least 18, with either four years of practical experience as a registered DOL apprentice plus the Iowa journeyperson exam for each discipline, or a master-level license in the same discipline from another jurisdiction. Since January 1, 2010 the four years must come from a registered apprenticeship; informal on-the-job time and helper time do not count (Iowa Code section 105.11(7)). You may apply to sit the exam up to 12 months before finishing the 48 months of credit.

Master: either a master license from another jurisdiction, or an Iowa journeyperson license plus two years of journeyperson experience in that discipline, then the Iowa master exam. A master plans or superintends the design, installation or repair of the systems and must know the governing codes (section 105.2).

An apprentice may never work without supervision. Rule 431.3(8) puts the duty on the employer: a contractor "shall not knowingly allow an apprentice employed by the contractor to perform work covered under Iowa Code Chapter 105 without supervision... by a master or journeyperson who is also employed by the contractor."

The Kirkwood exam: fees, format and passing score

Iowa uses one exam vendor for every discipline: Kirkwood Community College, not PSI, Prov or Pearson VUE. Kirkwood's own page lists 16 test cities; some DIAL license pages still print 15.

A score of 75 percent passes (rule 429.6(2)). Every exam is open book; bound code books with pre-added tabs are allowed, photocopies are not. Pass within one year of your original application or reapply, and a passing score expires two years after notification if you have not applied for the license.

Kirkwood sets the exam fee at $119 per attempt, nonrefundable, paid directly to Kirkwood rather than the state. Some DIAL pages still print older numbers ($99 for journeyperson, $95 for master); budget $119 since the vendor, not DIAL, sets that charge.

Step by step: applying for an Iowa plumbing license

1. Enroll in a U.S. DOL registered plumbing apprenticeship with an Iowa-licensed contractor that has a journeyperson or master on payroll.
2. Apply for the apprentice license through DIAL's licensing portal, $50 for a full period.
3. Log four years (48 months) of registered apprentice credit; you may apply to test up to 12 months early.
4. File the Exam Approval Application, $35 per discipline, at least 15 business days before you want to test.
5. Register with Kirkwood (319-398-1022 or online), pay $119, and pass the exam at 75 percent or better.
6. File the Post-Examination Licensure Application within two years; $180 for a full period, prorated to what remains of the current cycle.
7. Work two years as a licensed journeyperson under a master in that discipline.
8. Pass the master exam, then file for the master license, $240 for a full period.
9. To run a business, add the contractor license and DIAL registration, the insurance and bond, and name a master of record (see below).

Want the application done for you?

Steps 2, 4, 6 and 9 above are paperwork: an application, a fee, supporting documents, and a board that can bounce a filing back over a missing form. The Licensing Company's License Application Processing service prepares and submits a state contractor license application on your behalf: an eligibility audit before anything is filed, a document checklist, every state form prepared and reviewed line by line, submission the way the board requires, and the board's follow-up questions answered and resubmitted until the board decides.

It is a flat $999 per state application, paid up front. State fees, exam fees, background checks and fingerprinting still go to the state, not to us. The service does not promise approval, does not promise a timeline, and does not take an exam for you. Call 615-219-2110 or start at License Application Processing.

What an Iowa plumbing license costs

Full three-year fees, from DIAL's fee schedule and 481 IAC 428.1; mid-period licenses are prorated by one sixth for each six-month block already gone.

Add $25 for paper filing instead of the online portal. The exam itself adds $35 per discipline to apply plus $119 per attempt to Kirkwood. A 30 percent discount can cut the journeyperson, master and contractor figures; see below.

Contractor bond and insurance requirements

To contract, not just to work, Iowa requires both a PMSB contractor license and DIAL registration under Iowa Code chapter 91C, filed as one joint application.

Liability insurance: at least $500,000, from an insurer licensed in Iowa, cancellable only on 10 days' written notice to the board (section 105.19; rule 431.3(4)). Certificate holder: Bureau of Environmental Health & Contractor, Iowa Dept of Inspections, Appeals & Licensing, 6200 Park Ave Ste 100, Des Moines, IA 50321.

Surety bond: at least $5,000, same 10-day notice rule (431.3(3)). The obligee must be the contractor's own customers, not the State of Iowa or the board; DIAL accepts language like "licensee's Iowa customers," and a bond naming the state gets returned.

Out-of-state contractors registering under chapter 91C post a separate $25,000 surety bond on DIAL's form, unless prequalified to bid Iowa DOT work, in which case a letter suffices (section 91C.2). In-state contractors with employees also show proof of workers' compensation insurance, and every contractor needs a valid unemployment insurance number, even with no employees (myiowaui.org or 888.848.7442). A self-employed contractor may file a notarized Fee Exemption Form covering the DIAL registration portion only, if the contractor does not work with or for other contractors in the same phases of construction and does not pay more than $2,000 per year to employ others (section 91C.1(3)).

See contractor bond requirements by state and contractor insurance requirements by state for how Iowa compares.

How long it takes to become a licensed plumber in Iowa

Budget roughly six years for the full climb: four years of registered apprenticeship, the journeyperson exam, two more years working as a journeyperson, then the master exam. The apprentice and journeyperson stages cannot be shortened by informal experience; only DOL-registered apprenticeship time counts.

Processing itself is faster. The Exam Approval Application takes up to two weeks, and license applications generally take 4 to 6 weeks. Plan the exam date and license filing around those windows, not around when you finish your hours.

Renewal, the September 1 cliff and continuing education

Iowa runs three-year licensing periods; every license in the period expires at the same time regardless of issue date (section 105.9(7); rule 429.7(1)). The current period runs July 1, 2026 to June 30, 2029, the next July 1, 2029 to June 30, 2032; renewal opens May 1 of year three, and the statute wants the renewal application in at least 30 days before the expiration date (section 105.20(2)).

DIAL calls August 31 the end of the grace period; a license is valid for practice up to two months past expiration, then lapsed (rule 429.7(5)). Reinstatement after more than a year is tougher than the late fee table: a journeyperson or master either retakes the exam ($35 application plus the Kirkwood fee) or completes the continuing education for every period missed, at least half in person: 8 hours if expired under 2 years, 16 for 2 to 6 years, 24 for 6 to 9 years, 32 for 9 to 12 years (14, 28, 42 and 56 with multiple mechanical licenses). The reinstated license still runs only to the end of the current period, with no prorated discount. A contractor license expired more than a year cannot be renewed at all; the company refiles with the bond and insurance documents again. See contractor license renewal requirements by state and expired contractor license reinstatement.

Continuing education runs on a three-part formula under rule 481 IAC 432.2, with at least 8 hours required every three-year term:

The rest of each total is discipline-specific training: 4 hours for one license, 8 hours for the multi-license rows. At least half of every total must be taken in person, and both the instructor and the course must be pre-approved by the board, so an out-of-state online certificate does not automatically count. Apprentices and medical gas installers owe no CE hours. Rule 432.6 exempts active military service, a license issued with under a year left in the term, the first journeyperson renewal right after the apprentice license, government employees working abroad in their specialty, and anyone who met an equivalent requirement while licensed in another state. See contractor continuing education requirements by state.

The 30 percent discount many licensees never claim

Applying for or renewing more than one of the journeyperson, master or contractor licenses lets you deduct 30 percent from those fees (section 105.9(5)(b); rule 428.1(11)), as long as every license belongs to the same individual, none has lapsed more than a year, and they are bought in a single transaction (same day online, same envelope on paper). It excludes the $25 paper filing fee, the $150 contractor registration fee, and any late fee. Online filing calculates the discount automatically.

Two smaller breaks: folding an HVAC-refrigeration or hydronics license into a mechanical license costs $50 mid-period and nothing extra at renewal (rule 428.1(12)), and rule 428.3 waives the fee on a first Iowa license when household income sits at or below 200 percent of the federal poverty guidelines.

Specialty licenses and who is exempt

PMSB also issues narrower credentials under section 105.18(3): disconnect/reconnect plumbing technician, hearth systems, medical gas piping (NITC certified), private school or college routine maintenance, and HVAC service technician. A disconnect/reconnect technician works only from the shutoff valve to the appliance and may install a shutoff valve no more than three feet away (rule 431.7(4)); the private school license excludes furnaces, boilers, cooling appliances and water heaters over 100 gallons (rule 431.7(5)).

Section 105.11 exempts: a homeowner working on an existing principal residence that qualifies for the homestead tax credit; helpers doing general manual labor under a journeyperson or master, whose time never counts toward a journeyperson license; utility, rural water, railroad and government employees working for their own employer; engineers, architects, certified well contractors, LP gas installers and manufacturer representatives; pipe layers in the public right of way with no interior connections; landlords on their own properties; and unpaid volunteers. Everyone else needs the board's license (section 105.10).

What changes when you license a plumbing business

Working as a licensed plumber and contracting as a plumbing business are two different regulatory acts (see contractor license versus business license). Section 105.10(2) forbids a company from operating "unless at all times a licensed master... is employed by the person and is actively in charge" of the work. Rule 431.3(1) demands an active master license for each discipline the company contracts in. That person is the master of record.

Three rules follow, and each has cost Iowa contractors real work:

1. A master can be master of record for only one contractor per discipline at a time, absent prior board approval (rule 431.4(1)).
2. A master licensed in more than one discipline can serve different contractors in different disciplines: plumbing for one company, mechanical for another.
3. Losing your master of record starts two clocks at once. Rule 431.3(1) allows up to six months of continued operation after a master's employment ends, the relationship ends, or the master's own license lapses, is suspended or expires, but only if the contractor notifies the board within 30 days. Miss that notice and the grace period disappears. The departing master separately owes the board and the contractor the same 30-day notice (rule 431.4(4)).

Our Iowa master of record guide covers the certification form and what to do the week a master resigns.

If you are not yet eligible for your own journeyperson or master license, a qualifying agent lets your company hold the contractor license while you build your own hours. A qualifying agent qualifies the company as an owner or full-time W-2 employee who actually supervises the work, which is exactly what Iowa's master of record rule already requires: a master "employed by the person and... actively in charge" (105.10(2)). Start with what a qualifying agent is, then hire a qualifying agent. Weighing a looser arrangement first? Read can a qualifying agent be a 1099 contractor and qualifier: owner vs. employee.

Reciprocity and moving to Iowa

Iowa has one plumbing reciprocity agreement, approved in May 2016 with the South Dakota State Plumbing Commission: a South Dakota journeyperson or master plumbing license earned by written exam transfers to the same Iowa license without retesting. An Iowan licensee moving the other way pays $20 for the reverse written verification. There is no reciprocity for contractor licenses.

Everyone else uses licensure by verification (Iowa Code 272C.12; rule 481 IAC 430.4), which still requires the Iowa exam but allows a temporary license while it is pending. Section 105.18(5) separately waives the exam and experience requirements for active or retired military members who were deployed on active duty any time between July 1, 2008 and December 31, 2009 and who already passed a substantially similar exam or held a substantially similar license elsewhere. See our regional guides for Minnesota, Wisconsin and Missouri.

Penalties for unlicensed plumbing work

Section 105.27 lets the board impose a civil penalty of up to $5,000 per offense, with each day of a continued violation a separate offense. Section 105.29 makes opening an office or advertising prima facie evidence of practicing, and rule 431.2(5) bars a lapsed licensee from operating as a contractor or working in the trade at all.

Iowa plumbing license FAQ

How do I get a plumbing license in Iowa? Enroll in a DOL registered apprenticeship, log four years of credit, pass the Kirkwood journeyperson exam, work two more years, then pass the master exam. Each stage has its own license and fee through DIAL.

Do I need insurance to be a licensed plumbing contractor in Iowa? Yes. A PMSB contractor license requires at least $500,000 in public liability insurance from an insurer licensed in Iowa, on top of the $5,000 surety bond. An individual journeyperson or master license carries no separate insurance requirement.

How do I register for the Iowa plumbing exam? File the Exam Approval Application with the board first ($35 per discipline, at least 15 business days before testing). Once approved, register directly with Kirkwood Community College by phone (319-398-1022) or online and pay the $119 exam fee.

Can I get an Iowa journeyperson license with four years of on-the-job experience? Not on its own. Since January 1, 2010 the four years must come from a U.S. Department of Labor registered apprenticeship, and informal helper time does not count.

How much does it cost to become a licensed plumbing contractor in Iowa? For a full three-year period: $250 PMSB contractor license plus $150 DIAL registration ($400), plus the $500,000 insurance and $5,000 bond. Individual licenses run $50 apprentice, $180 journeyperson and $240 master, each prorated mid-cycle. Fees change; verify with DIAL.

What does the Iowa plumbing and mechanical systems bond require? A $5,000 surety bond from a surety licensed in Iowa, with 10 days' notice to the board before cancellation, naming the contractor's customers, not the state, as obligee. Out-of-state contractors also post a separate $25,000 bond under chapter 91C.

Do I need a separate license for HVAC or mechanical work? Yes. A master plumbing license does not authorize HVAC-refrigeration or mechanical work, and a company needs a master of record in each discipline it contracts in. See the Iowa HVAC license guide.

How long can my company operate if the master of record quits? Up to six months, but only if you notify the board within 30 days of the separation. Miss the notice and the grace period is gone, even if six months have not passed.

What if I cannot qualify for my own license yet but need to bid work now? A qualifying agent can serve as your company's master of record while you build toward your own journeyperson or master license. See hire a qualifying agent.

Sources

• Iowa DIAL, Plumbing & Mechanical Systems Licensure hub (retrieved 2026-10-07)
• Iowa DIAL, Licensing Period & Fees (retrieved 2026-10-07)
• Iowa DIAL, Apprentice License (retrieved 2026-10-07)
• Iowa DIAL, Journey Level License (retrieved 2026-10-07)
• Iowa DIAL, Master Level License (retrieved 2026-10-07)
• Iowa DIAL, Contractor License (retrieved 2026-10-07)
• Iowa DIAL, Renew or Update a PMSB License (retrieved 2026-10-07)
• Iowa DIAL, PMSB Continuing Education & Training (retrieved 2026-10-07)
• Iowa DIAL, Contractor Registration (retrieved 2026-10-07)
• Kirkwood Community College, State Disciplines exams (retrieved 2026-10-07)
• Iowa Code 2026, chapter 105, Iowa Legislature (retrieved 2026-10-07)
• Iowa Code 2026, chapter 91C, Iowa Legislature (retrieved 2026-10-07)
• 481 IAC chapter 425, State Plumbing Code (retrieved 2026-10-07)
• 481 IAC chapter 428, Licensure Fees (retrieved 2026-10-07)
• 481 IAC chapter 429, Application, Licensure, Examination (retrieved 2026-10-07)
• 481 IAC chapter 430, Reciprocity and Licensure by Verification (retrieved 2026-10-07)
• 481 IAC chapter 431, Licensee Practice (retrieved 2026-10-07)
• 481 IAC chapter 432, Continuing Education (retrieved 2026-10-07)
• The Licensing Company, License Application Processing (retrieved 2026-10-07)

Next steps

If you are climbing the ladder yourself, the step-by-step list above is the whole sequence; the Kirkwood exam and the 30 percent multi-license discount are the two places people leave time and money on the table. If your company needs the paperwork handled instead of the licensing itself, our License Application Processing service files the state application on your behalf. And if the constraint is a master of record, not a form, call 615-219-2110 or start at hire a qualifying agent and we will map the disciplines you need covered against your next bid.

Related: Iowa contractor license · Iowa electrician license · Iowa HVAC license · Iowa master of record · how to get a plumbing contractor license · all state guides