Iowa licenses plumbers at the state level, and that state license preempts every city and county in Iowa. If you get licensed in Des Moines or Cedar Rapids under some local ordinance, that ordinance has been void since July 1, 2009. There is one license, and it comes from the state.
Here is how the system actually works, verified against Iowa Code chapter 105 and the board’s administrative rules.
Who runs plumbing licensing in Iowa
The Plumbing and Mechanical Systems Board (PMSB), housed within the Iowa Department of Inspections, Appeals, and Licensing (DIAL).
Note the agency name, because most guides get this wrong. Plumbing licensing used to sit with the Iowa Department of Public Health. It does not anymore. The 2023 state reorganization moved it, and the board’s rules formally moved from Public Health[641] to Inspections and Appeals[481] effective April 2, 2025. If a site tells you to contact IDPH, that site is out of date.
Board page: DIAL Plumbing and Mechanical Systems Board
Licensure hub: Iowa plumbing licensure
Statute: Iowa Code chapter 105
Phone: 866-280-1521
State preemption: Iowa Code 105.17 says the state license supersedes and preempts all city and county plumbing licensing. Cities can still charge permit and inspection fees, but they cannot make you carry a second license.
The license tiers Iowa actually has
Iowa uses the word journeyperson, not journeyman. Use their word on the application.
| Tier | What it is |
|---|---|
| Apprentice | One apprentice license covers all plumbing and mechanical trades |
| Journeyperson | Iowa calls it a “journey level license” |
| Master | The skill ceiling for an individual |
| Contractor | Issued to the person or business, not a skill level |
There are also specialty credentials: disconnect/reconnect plumbing technician, private school or college routine maintenance, and medical gas system installer.
What it takes at each level
Apprentice. 18 or older, high school diploma or GED, and enrolled in a U.S. Department of Labor registered apprenticeship program. You supply your apprentice ID, start date, and sponsor program number. No exam.
Journeyperson. Four years of practical experience as an apprentice. Since January 1, 2010 those four years must be inside a USDOL-registered apprenticeship program. Then pass the state journeyperson exam.
Worth knowing: Iowa states this requirement in years, not hours. There is no 8,000-hour figure anywhere in Iowa Code chapter 105 or the board rules, despite what a lot of sites claim. Do not go looking for an hour count that does not exist.
Master. Pass the master exam. To be eligible to sit for it you need either a journeyperson license plus two years of journeyperson work experience in that discipline, or an existing master license in the same discipline from another jurisdiction. The two-year requirement comes from board rule 481 IAC 429.2(3), not from the statute itself.
Contractor. 18 or older, a permanent place of business, and either hold a master license yourself or employ a “master of record” for each discipline you work in. Plus insurance and a bond (below), plus separate DIAL contractor registration under Iowa Code chapter 91C. No trade exam for the contractor license itself.
One detail that catches people: a master can be master of record for only one contractor per discipline. If your master of record leaves, you have to notify the board within 30 days and you get a six-month grace period to replace them.
The exam
Iowa’s exam vendor is Kirkwood Community College, with testing sites across the state.
- Written and proctored, in person or online
- Passing score is 75 percent (481 IAC 429.6(2)(d))
- Exam approval is good for one year, unlimited attempts inside that year
- A passing score expires if you do not apply for licensure within two years
- Passing does not license you. You file a separate post-examination licensure application
There is a $35 exam approval application fee paid to the board, plus a separate exam fee paid directly to Kirkwood. We are not printing a Kirkwood dollar figure here because DIAL’s own journey-level and master-level pages currently quote two different amounts. Check with Kirkwood for the current number.
Fees
All Iowa licenses run on a three-year cycle, and these are the full three-year amounts.
| License | Fee |
|---|---|
| Apprentice | $50 |
| Journeyperson | $180 |
| Master | $240 |
| Contractor license | $250 |
| Contractor registration (DIAL, on top) | $150 |
| Medical gas installer | $75 |
| Exam approval application | $35 |
| Paper application surcharge | $25 |
New licenses are prorated by one sixth per six-month block left in the cycle. If you are getting two or more licenses in one transaction, there is a 30 percent multiple-license discount on the license fees.
Late fees: nothing through July 31, $60 in August, $100 after August 31.
Iowa also waives fees entirely if your household income is at or below 200 percent of federal poverty guidelines and it is your first Iowa license, and waives the initial fee plus one renewal for honorably discharged veterans within five years of discharge.
Bond and insurance
Only the contractor license carries these. Apprentices, journeypersons, and masters have no individual bond or insurance requirement.
- Public liability insurance: $500,000 minimum. Not $1 million, whatever you have read
- Surety bond: $5,000 minimum, a performance bond running to your customers, not to the state
- Both need a clause giving the board 10 days’ written notice before cancellation
- Out-of-state contractors file an additional $25,000 surety bond with DIAL under chapter 91C
Renewal and continuing education
Iowa runs a three-year license period. Everything expires June 30 of the third year regardless of when you were issued. The current period runs July 1, 2026 through June 30, 2029.
- Renewal opens May 1 of the final year
- No late fee through July 31, and your license stays valid for practice through August 31
- Lapsed more than a year and you either retake the exam or complete every missed CE period
Continuing education: 8 classroom hours per three-year term for an active or inactive journeyperson or master. For a single plumbing license that breaks down as 2 hours Iowa plumbing code, 4 hours plumbing discipline, 2 hours Iowa OSHA safety.
Up to half can be online, the rest must be in person. Both the course and the instructor have to be pre-approved by the board. Apprentices have no CE requirement. You self-report hours at renewal and keep the certificates in case of audit.
Reciprocity
One state. South Dakota. Plumbing only. Journeyperson and master only.
That is the whole list. The board is authorized to sign more agreements under Iowa Code 105.21 and has signed exactly one, back in May 2016. Anyone telling you Iowa reciprocates with Minnesota, Nebraska, Wisconsin, Illinois, or North Dakota is guessing.
The South Dakota agreement only covers licenses originally earned by written examination. If you were grandfathered in, you are not eligible either direction. You also need a non-Iowa resident address at the time you apply.
Two other paths exist that are not reciprocity but do the same job:
Licensure by verification (Iowa Code 272C.12) for people becoming Iowa residents. Requires Iowa residency, verification sent directly from your old jurisdiction, and passing the Iowa exam. A temporary license can be issued while you sort the exam.
Licensure by work experience (Iowa Code 272C.13) for people moving from a state that did not license the trade at all. Requires three or more years of full-time work in the preceding four years, where full time means 1,700 hours a year.
Recent changes worth knowing
- Board rules were substantively rewritten effective June 19, 2024
- Rules renumbered from Public Health[641] to Inspections and Appeals[481] on April 2, 2025
- A new three-year licensing period started July 1, 2026
- Senate File 2218, signed June 2, 2026, requires lawful-presence verification for all Iowa professional licenses effective July 1, 2026
- Iowa currently runs the 2024 Uniform Plumbing Code and the 2024 International Mechanical Code
Frequently asked questions
Does Iowa require a plumbing license for all plumbing work?
Yes, and it is a single statewide license. Cities cannot issue or require their own plumbing license. They can still require permits and inspections.
How long does it take to get an Iowa journeyperson license?
Four years in a USDOL-registered apprenticeship, then the exam. You may be able to apply to sit for the exam up to 12 months before finishing your apprentice credit under rule 481 IAC 429.6(3)(j), though DIAL’s own exam page currently contradicts itself on this point. Ask the board.
Do I need a contractor license to run my own plumbing business in Iowa?
Yes. A master license lets you do the work. The contractor license lets you contract for it, and it requires a permanent place of business, $500,000 liability insurance, a $5,000 bond, and separate chapter 91C registration.
Can I use my license from another state in Iowa?
Only if it is South Dakota, plumbing, earned by exam. Otherwise you go through licensure by verification or by work experience, and you will still have to pass the Iowa exam in most cases.
Before you apply
Iowa is one of the cleaner states to get licensed in because there is exactly one license and one board. The friction is the four-year registered apprenticeship, which you cannot shortcut.
Requirements and fees change, and we found several DIAL pages carrying stale figures while researching this. Confirm anything you are relying on with the board at 866-280-1521 before you apply. This is not legal advice.
