Wisconsin plumbing license requirements and insurance
To work for yourself as a plumber in Wisconsin, you need the Master Plumber license. Wisconsin has 3 plumbing license types, and which one you need depends on the work you take on. The state sets no minimum liability insurance, and workers' comp is required from the first employee. The state does not ask for a bond.
1Who needs a plumbing license in Wisconsin? What is this?
Master Plumber: anyone who takes responsibility for plumbing installation or modification jobs and directs journeyman plumbers.
| License | Who needs it | What it covers |
|---|---|---|
| Plumbing Apprentice | Anyone learning plumbing under a licensed plumber before taking the journeyman exam. | Plumbing work under general supervision. |
| Journeyman Plumber | Anyone who installs plumbing, working under the general supervision of a Master Plumber, Master Plumber Restricted, or Utility Contractor. | Plumbing installation. When supervised by a restricted master or a utility contractor, limited to the type of work that supervisor's license covers. |
| Master Plumber | Anyone who takes responsibility for plumbing installation or modification jobs and directs journeyman plumbers. | Full plumbing work and legal responsibility for the licensed and registered people used on a job. |
2Who issues plumber licenses in Wisconsin? What is this?
Wisconsin Department of Safety and Professional Services (DSPS) issues plumbing licenses in Wisconsin.
See how this compares in every state: How to check a contractor's license, state by state
| Name | Wisconsin Department of Safety and Professional Services (DSPS) |
|---|---|
| Website | dsps.wi.gov |
| Look up a license | license.wi.gov |
| The law | Wis. Stat. ch. 145, Plumbing |
| The rulebook | Wis. Admin. Code ch. SPS 305, subchapter IX |
3How to become a plumber in Wisconsin What is this?
Wisconsin has 3 licenses that matter to a plumber: Plumbing Apprentice, Journeyman Plumber, Master Plumber. Each is below, with what you need before you apply.
| License | Experience required | Exam |
|---|---|---|
| Plumbing Apprentice | None to register. | — |
| Journeyman Plumber | Complete a recognized Wisconsin plumbing apprenticeship, or, for an out-of-state apprenticeship, a 5-year program with at least 576 hours of related instruction. | The Journeyman Plumber license exam. |
| Master Plumber | At least 1,000 hours a year as a licensed Wisconsin Journeyman Plumber for at least 3 years, or a civil, mechanical or other approved engineering degree. | The Master Plumber license exam. |
4How much does a plumbing license cost in Wisconsin? What is this?
The government fees on this page add up to about $695 in Wisconsin. Add insurance, tools, and a vehicle to get the real number.
| License | Renewal | Late renewal |
|---|---|---|
| Plumbing Apprentice | $15 | — |
| Journeyman Plumber | $180 | $25 |
| Master Plumber | $500 | $25 |
Added up
| Government fees, added up | $695 |
|---|
Adds the 2024 renewal-table figures for Journeyman Plumber ($180) and Master Plumber ($500), plus the Plumbing Apprentice registration ($15), since initial application fees are not published outside the LicensE portal. Leaves out exam fees, insurance and tools.
5How much plumbing insurance do you need in Wisconsin? What is this?
Wisconsin sets no minimum liability insurance for this license. Customers and general contractors usually ask for $1,000,000 anyway. Workers' comp is required from the first employee.
| Minimum liability insurance | None required by the state |
|---|---|
| Type of policy | None found. |
| How we know | Chapter 145's own section list, read in full on 2026-09-21 (§§ 145.01 to 145.26), has no insurance or bond section for plumbers. |
| Workers' comp required? | Yes |
| Who can opt out |
|
| Workers' comp: if you skip it | Wisconsin does not publish the amounts. Ask the Department of Workforce Development what applies to you. |
6Does Wisconsin check your credit for a plumber license? What is this?
Wisconsin does not check your credit for this license.
| Credit score you need | None found. |
|---|---|
| How we know | Chapter 145, read for its section list on 2026-09-21, sets no credit or financial test for a plumbing license. |
7Does a plumber need a bond in Wisconsin? What is this?
Wisconsin does not require a state bond for this license. Some cities ask for one before they issue permits.
| Does the state require a bond? | No |
|---|---|
| Amount | Not listed yet |
No bond requirement found in ch. 145.
8Where must a Wisconsin plumber show the license number? What is this?
In Wisconsin: a master plumber advertising in printed material for the public must include their master plumber license number. A plumbing contractor advertising the same way must include the license number of the master plumber it employs.
| The rule | A master plumber advertising in printed material for the public must include their master plumber license number. A plumbing contractor advertising the same way must include the license number of the master plumber it employs. |
|---|---|
| On ads | Applies to any printed material meant for public distribution. |
| On quotes, contracts, and invoices | Not separately addressed; the rule as written covers advertising, not invoices. |
| If you forget | Working or advertising this way without the required license is a fine of $100 to $500, or up to 30 days in jail, or both. Each day counts as a separate offense. |
9Does a plumber charge sales tax on labor in Wisconsin? What is this?
In Wisconsin, not taxed when the work is a real property construction activity, such as installing a water heater or repiping a house. Materials the plumber buys and installs are taxed to the plumber, not the customer. The rest of the rules are below.
See how this compares in every state: Can you charge sales tax on labor? The rule in 25 states
| Tax rate | 5% state rate. Some counties add a 0.5% county tax, and some add a 0.1% stadium tax, so the total can run from 5% to 5.6% depending on the county. |
|---|---|
| Labor | Not taxed when the work is a real property construction activity, such as installing a water heater or repiping a house. Materials the plumber buys and installs are taxed to the plumber, not the customer. |
| Who pays tax on materials | The plumber, as the consumer of the materials, unless the job is a sale and service of personal property, in which case the customer pays tax on the whole bill. |
| The exception that catches people out | Repairing or servicing an item that keeps its character as personal property, rather than installing it into the building, is a taxable retail sale, and both labor and parts are taxed. |
10Getting paid: lien and notice deadlines for a Wisconsin plumber What is this?
If you are not paid in Wisconsin, a lien on the property is your backstop, but only if your notice goes out on time: contractor hired by the owner, with no written contract: within 10 days of first work or materials. Subcontractor or supplier: within 60 days of first work or materials.
- Day 0Your first day on the job
The clock starts here.
- Day 10Send your notice
Contractor hired by the owner, with no written contract: within 10 days of first work or materials. Subcontractor or supplier: within 60 days of first work or materials.
- Day 30File your lien
Within 6 months of the last work or materials, filed with the clerk of circuit court in the county where the property is. At least 30 days before filing, a written notice of intent to file must be served on the owner. A copy of the filed claim must be served on the owner within 30 days after filing.
Each day count is counted from the day the rule beside it names, which is not always the same day. Read the sentence under each one.
| Who has to send a notice |
|
|---|---|
| Send your notice by | Contractor hired by the owner, with no written contract: within 10 days of first work or materials. Subcontractor or supplier: within 60 days of first work or materials. |
| File your lien by |
|
| File a lawsuit by | Within 2 years of filing the claim. |
11How do you renew a plumbing license in Wisconsin? What is this?
The Master Plumber renews every 4 years, by March 31.
| License | Renewal |
|---|---|
| Plumbing Apprentice | Annual, from date of issuance. |
| Journeyman Plumber | Every 4 years, by March 31. |
| Master Plumber | Every 4 years, by March 31. |
Renewal fees are in what the license costs. The official page for each license is linked under how you get it.
12What catches people out in Wisconsin What is this?
The things people get wrong or do not expect about Wisconsin, in a few sentences.
- A master plumber's license renewal, at $500 every 4 years, is the single highest trades renewal fee DSPS publishes for any of the three trades.
- Advertising as a master plumber or plumbing contractor without putting the master plumber's license number in the ad is a fine of $100 to $500 a day, and can mean 30 days in jail.
- A journeyman plumber's supervision requirement changes with who supervises: under a Master Plumber Restricted or a Utility Contractor, the journeyman is limited to that supervisor's narrower scope of work.
- An out-of-state journeyman plumber can qualify by 5 years of practice alone, without a Wisconsin exam, if the department finds their home state's rules substantially similar to Wisconsin's and they have no discipline history.
13Where these numbers come from
The labels under each table are explained on how to read a page.
- docs.legis.wisconsin.gov/statutes/statutes/145
- dsps.wi.gov/Pages/Programs/Plumbing/Default.aspx
- docs.legis.wisconsin.gov/statutes/statutes/145/11
- dsps.wi.gov/Credentialing/Trades/TradesRenewalDatesFees.pdf
- dsps.wi.gov/Credentialing/Trades/fm3126.pdf
- dsps.wi.gov/Credentialing/Trades/fm3129.pdf
- dwd.wisconsin.gov/wc/employers/
- revenue.wi.gov/dor%20publications/pb207.pdf
- docs.legis.wisconsin.gov/statutes/statutes/779/I/02
- docs.legis.wisconsin.gov/statutes/statutes/779/I/06
- dsps.wi.gov/Pages/Professions/JourneymanPlumber/Default.aspx