- Iowa requires plumbing contractors to hold a state contractor license from the Plumbing and Mechanical Systems Board and to register with DIAL.
- Journeyperson: four years as an apprentice in a registered apprenticeship, then pass the exam. Master: hold a journeyperson license with two years of work experience, or a master license from another jurisdiction.
- Plan for a trade exam.
- Pay runs from about $21.88 an hour for the lowest-paid tenth of plumbers to $46.87 for the top tenth.
- Jobs are projected to grow 8.8% from 2022 to 2032, faster than the 2.3% projected nationally.
The path in Iowa, step by step
Iowa licenses plumbing work at the state level through the Iowa Plumbing and Mechanical Systems Board, Department of Inspections, Appeals, and Licensing (DIAL). These are the steps it lays out, in order.
- Work as an apprentice in a US Department of Labor registered apprenticeship for four years.
- Pass the Iowa journeyperson plumbing exam and get your journeyperson license.
- After two years as a journeyperson, file the exam approval application ($35) and pass the master exam at Kirkwood.
- Apply for your master plumber license.
- Get $500,000 liability insurance, a $5,000 surety bond and an Iowa unemployment insurance number.
- Apply for the plumbing contractor license and DIAL contractor registration in one application.
The full license guide, with every fee and form: plumbing license in Iowa.
Finding an apprenticeship in Iowa
Iowa runs Registered Apprenticeship through its own State Apprenticeship Agency, recognized by the U.S. Department of Labor to register and oversee programs there. Its staff are state employees, and it may use the federal paperwork or forms of its own. Apprenticeship.gov lists the Iowa Apprenticeship Office as the contact.
Either way, a registered program means paid work with a mentor, raises as you progress, classroom instruction and a credential recognized in every state. Search open spots in the Apprenticeship Job Finder.
Across the country. Most plumbers learn the trade in a 4 or 5 year apprenticeship, with about 2,000 hours of paid on-the-job training plus some classroom instruction each year.
License levels and exams in Iowa
The license to aim for: Plumbing contractor license (you hold, or employ, a licensed master plumber).
Trade exam. Iowa Plumbing and Mechanical Systems Board master exam for plumbing, given by Kirkwood Community College.
Keeping it. Licenses run on a 3-year period and expire June 30 (valid through Aug 31). At least 8 hours of approved continuing education each 3-year term.
Coming from another state. Iowa has a reciprocity agreement with South Dakota for journeyperson and master plumbing licenses earned by written exam.
| License | What it covers |
|---|---|
| Master plumber | Plans and supervises the design, installation and repair of plumbing, and can run the business side. |
| Journeyperson plumber | Does plumbing work under the supervision of a licensed master. |
| Plumbing contractor | The business license for anyone who does plumbing work for customers under a contract. |
What the Iowa license costs
The fees the Iowa Plumbing and Mechanical Systems Board, Department of Inspections, Appeals, and Licensing (DIAL) lists. Exam fees from a testing company, insurance and any bond come on top.
| Fee | Amount |
|---|---|
| Exam approval application, per trade exam | $35 |
| Master exam fee paid to Kirkwood, per attempt | $95 |
| Master license, applied for July 1 to Dec. 31 of year 1 of the 3-year period (less later) | $240 |
| Contractor license plus contractor registration, July 1 to Dec. 31 of year 1 (less later) | $400 |
What plumbers earn in Iowa
The median plumber in Iowa earned $30.72 an hour in May 2025, 26th of 51 states, with 5,730 on payrolls. The national median was $30.67.
At the bottom of the range, a quarter of plumbers in Iowa earned under $24.95 an hour and a tenth under $21.88. At the top, a quarter earned over $41.02 and a tenth over $46.87.
| Pay level | Hourly | Yearly |
|---|---|---|
| 10th percentile | $21.88 | $45,510 |
| 25th percentile | $24.95 | $51,890 |
| Median | $30.72 | $63,890 |
| 75th percentile | $41.02 | $85,320 |
| 90th percentile | $46.87 | $97,500 |
Every state, the neighbors and what a business should charge: plumber salary in Iowa.
Jobs ahead in Iowa
Iowa's labor market office projects jobs for plumbers growing from 7,460 in 2022 to 8,120 in 2032, a change of 8.8%. Counting people who retire or change careers, that is about 730 openings a year.
Jobs are projected to grow 8.8% from 2022 to 2032, faster than the 2.3% projected nationally, ranking 23rd of the 50 states in the file.
These are the state's own long-term projections, published together on Projections Central for the occupation group plumbers, pipefitters, and steamfitters.
Starting your own plumber business in Iowa
To contract on your own in Iowa, the license is the Plumbing contractor license (you hold, or employ, a licensed master plumber).
Insurance. Public liability insurance of at least $500,000. Workers' compensation if you have one or more employees.
Bond. Surety bond of at least $5,000. Out-of-state contractors also file a $25,000 bond for contractor registration.
Pricing comes next. Paying yourself the Iowa median of $30.72 an hour, the labor rate calculator's starting numbers (one person, 2 unbilled hours a day, $90,000 of overhead, 15% profit) come to $124.54 per billable hour. Try your own in the plumber labor rate calculator.
The full checklist is in how to start a plumbing business. The free Koira Office plan gives you a website on a Koira address, estimates customers sign with a deposit, invoices with card payments and your day's jobs in one place, with no per-person fee. See the plans.
Where this comes from
The license steps, fees and rules are from the official pages below, read on the date shown. Pay is the BLS May 2025 state estimate, the job outlook is Iowa's own long-term projection, and the apprenticeship details are from the U.S. Department of Labor. A detail an official page did not confirm is left out.
- PMSB home (checked 2026-10-08)
- Contractor license (checked 2026-10-08)
- Master license (checked 2026-10-08)
- Journey license (checked 2026-10-08)
- License period and fees (checked 2026-10-08)
- Plumbing and mechanical licensure FAQ (checked 2026-10-08)
- U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics, May 2025, SOC 47-2152
- Projections Central, long-term occupational projections 2022 to 2032 (state labor market offices) (checked 2026-10-09)
- U.S. Department of Labor, Apprenticeship System (Office of Apprenticeship and State Apprenticeship Agencies) (checked 2026-10-09)
- U.S. Department of Labor, State Offices (checked 2026-10-09)
- U.S. Department of Labor, Registered Apprenticeship Program (checked 2026-10-09)
- BLS Occupational Outlook Handbook, Plumbers, Pipefitters, and Steamfitters (checked 2026-10-09)
Training, schools and certifications for every state: how to become a plumber.