Colorado plumbing license requirements and insurance
To work for yourself as a plumber in Colorado, you need the Master Plumber license. Colorado has 5 plumbing license types, and which one you need depends on the work you take on. The state's minimum liability insurance is $300,000 for injury and $100,000 for property damage, and workers' comp is required from the first employee. The state does not ask for a bond.
Who it applies to
1Who needs a plumbing license in Colorado? What is this?
Plumbing Contractor registration: any business that offers plumbing work to the public. The person holds the license; the company holds the registration
| License | Who needs it | What it covers |
|---|---|---|
| Residential Plumber | Anyone who installs plumbing in homes of one to four families, up to two stories, and does not hold a journeyman or master license | Plumbing in one- to four-family homes no more than two stories tall. Working on a commercial site means registering as an apprentice again |
| Journeyman Plumber | Anyone who installs, alters or repairs plumbing in any building while working for a plumbing contractor | All plumbing work, in homes and in commercial buildings, under a plumbing contractor |
| Master Plumber | The person who plans, lays out and supervises plumbing work. Every plumbing contractor must be one or employ one full time | All plumbing work, plus the right to be the master of record for one plumbing contractor |
| Plumbing Contractor registration | Any business that offers plumbing work to the public. The person holds the license; the company holds the registration | Lets the business offer plumbing work to the public. All work is supervised by the company's master plumber. Whether the company or the plumber pulls the permit is set by your city |
| Backflow prevention devices, when no plumbing license is needed | Since 28 March 2025 you do not need a plumbing license to inspect, test or repair a backflow prevention device. You still need one to install or remove a device, except on a stand-alone fire suppression sprinkler system, where no license is needed either | — |
| Plumbing Apprentice registration | Anyone learning the trade while working for a plumbing contractor or under a licensed plumber | — |
Who runs it
2Who issues plumber licenses in Colorado? What is this?
Colorado State Plumbing Board, inside the Division of Professions and Occupations at the Department of Regulatory Agencies (DORA) issues plumbing licenses in Colorado.
See how this compares in every state: How to check a contractor's license, state by state
| Name | Colorado State Plumbing Board, inside the Division of Professions and Occupations at the Department of Regulatory Agencies (DORA) |
|---|---|
| Website | dpo.colorado.gov |
| Look up a license | apps2.colorado.gov |
| The law | Colorado Revised Statutes, Title 12, Article 155, headed Plumbers |
| The rulebook | Plumbing Rules and Regulations, 3 CCR 720-1 |
| City rules | Cities and counties may license plumbing contractors too, but they cannot stop a state license holder from working. Denver charges $160 for a two-year plumbing contractor license and asks to see your state contractor card first. |
Taken from the linked page, not separately checked
·8 official pages
- leg.colorado.gov/bills/hb24-1344
- dpo.colorado.gov/Plumbing
- apps2.colorado.gov/dora/licensing/Lookup/LicenseLookup.aspx
- colorado.public.law/statutes/crs_title_12_article_155
- law.cornell.edu/regulations/colorado/department-700/division-720/3-CCR-720-1
- colorado.public.law/statutes/crs_12-155-121
- denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Community-Planning-and-Development/Contractor-Licensing/CL-Resources-and-Downloads/Fees-for-Contractor-Licenses-and-Supervisor-Certificates
- denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Community-Planning-and-Development/Contractor-Licensing/Contractor-Licenses/Apply-for-a-Contractor-License
Getting licensed
3How to become a plumber in Colorado What is this?
Colorado has 6 licenses that matter to a plumber: Residential Plumber, Journeyman Plumber, Master Plumber, Plumbing Contractor registration, Backflow prevention devices, when no plumbing license is needed, Plumbing Apprentice registration. Each is below, with what you need before you apply.
| License | Experience required | Exam |
|---|---|---|
| Residential Plumber | 3,400 hours of plumbing work. Trade school hours count one for one, up to one year. Military plumbing experience counts one month for every six, up to one year | Yes, run by PSI Services for the board. 100 multiple-choice questions in 240 minutes. You need 70 percent, and it is usually open book. Results come back as pass or fail only, and you cannot review your paper |
| Journeyman Plumber | 6,800 hours of plumbing work. Trade school hours count one for one, up to one year. Graduates of a board-approved community college or trade school program get one year of credit | Yes, run by PSI Services for the board. 100 multiple-choice questions in 240 minutes. You need 70 percent, and it is usually open book. Results come back as pass or fail only |
| Master Plumber | 8,500 hours of plumbing work. The same education credits apply as for the journeyman license | Yes, run by PSI Services for the board. 120 multiple-choice questions in 270 minutes. You need 75 percent, and it is usually open book. Results come back as pass or fail only |
| Plumbing Contractor registration | — | No. The master plumber has already passed it |
| Backflow prevention devices, when no plumbing license is needed | — | — |
| Plumbing Apprentice registration | — | — |
What it costs
4How much does a plumbing license cost in Colorado? What is this?
The government fees on this page, added up.
| License | Application | First registration | Renewal | Processing fee |
|---|---|---|---|---|
| Residential Plumber | $100 | — | $100 | — |
| Journeyman Plumber | $120 | — | $120 | — |
| Master Plumber | $140 | — | $140 | — |
| Plumbing Contractor registration | — | — | — | null |
| Plumbing Apprentice registration | — | $30 | — | — |
Added up
| Government fees, added up | Not listed yet |
|---|
We print no total, because Colorado publishes none of these fees. The amounts shown above come from the board's own guide where it gives them. The master exam, the master license and the contractor registration are the main costs. Insurance, tools, a vehicle and city permits come on top.
Our estimate
Insurance
5How much plumbing insurance do you need in Colorado? What is this?
The least liability insurance Colorado lets a plumber work with is $300,000 for injury and $100,000 for property damage. Most customers ask for more. Workers' comp is required from the first employee.
| Minimum liability insurance | $300,000 |
|---|---|
| Minimum liability insurance (property damage) | $100,000 |
| Type of policy | General liability cover of at least $300,000 and property damage cover of at least $100,000 |
| Who this applies to | Anyone who runs a plumbing business and registers it as a plumbing contractor |
| Who must be named on the certificate | Not stated in the board guide |
| Workers' comp required? | Yes |
| Workers' comp: what to know | Every employer with one or more employees must carry it, through Pinnacol Assurance, a private insurer, or a self-insurance permit. The plumbing board will not register your company until you show you comply. |
| Who can opt out | A corporate officer or an LLC member who owns at least 10 percent of the business and runs it can reject cover in writing, sent by certified mail. In construction, a contractor with no employees must still be covered, unless they file a rejection of coverage with the state |
| Workers' comp: if you skip it | Up to $250 a day for a first failure to carry cover, and $250 to $500 a day for any later one |
Checked by software against the official page
·10 official pages
- drive.google.com/file/d/1qj5xUjZrBCbTDkd7GdhQQY7qNnIx5xks/view
- dpo.colorado.gov/Plumbing/Applications
- law.cornell.edu/regulations/colorado/department-700/division-720/3-CCR-720-1
- colorado.public.law/statutes/crs_12-155-108
- colorado.public.law/statutes/crs_8-40-203
- colorado.public.law/statutes/crs_8-44-101
- colorado.public.law/statutes/crs_8-41-202
- colorado.public.law/statutes/crs_8-43-409
- cdle.colorado.gov/dwc/employers/insurance-coverage
- cdle.colorado.gov/dwc/employers/independent-contractors-and-coverage-exemptions
Money checks
6Does Colorado check your credit for a plumber license? What is this?
Colorado does not check your credit for this license.
| Credit score you need | None. Colorado does not check your credit, net worth or bank balance for a plumbing license or a contractor registration |
|---|---|
| If your score is lower | Not needed |
| How we know | The registration section of the law lists three conditions, and money is not one of them. The board rules have no section on finances |
Checked by a person against the official page
Bonds
7Does a plumber need a bond in Colorado? What is this?
Colorado 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 | None required by the state |
The state does not ask for a bond (a promise, backed by an insurance company, that customers can be paid if you do not finish the job). Neither the plumbing law nor the board rules mention one. Cities may ask for their own bond before they let you pull permits, so check with your city.
Checked by a person against the official page
Showing your number
8Where must a Colorado plumber show the license number? What is this?
In Colorado: since July 1, 2025 every bid sheet and every bill must show your plumbing contractor registration number and your master plumber's license number.
| On quotes, contracts, and invoices | Since July 1, 2025 every bid sheet and every bill must show your plumbing contractor registration number and your master plumber's license number |
|---|---|
| On ads | Your website must show both numbers. Only a licensed person may use the words master plumber, journeyman plumber or residential plumber in any ad |
| On your vehicles | Both numbers go on your vehicles, in at least two places, in letters and numbers at least two inches tall |
| If you forget | The board issues citations with fines from $50 to $2,000 a day, rising for repeat offenses, and can suspend or revoke a license |
Checked by a person against the official page
Tax
9Does a plumber charge sales tax on labor in Colorado? What is this?
In Colorado, colorado does not tax your labor. The tax falls on the materials, and how it is paid depends on how you bill. 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
| Labor | Colorado does not tax your labor. The tax falls on the materials, and how it is paid depends on how you bill |
|---|---|
| Materials | You are treated as the final buyer of pipe, fittings and fixtures that become part of a building. You pay sales tax when you buy them |
| When you quote one total price | You pay tax at the supply house on what the materials cost you, and you do not charge the customer any tax |
| When you bill time and materials | You become a retailer for that job. You need a sales tax license, and you charge the customer tax on the marked-up price of the materials |
| When you are the subcontractor | A subcontractor is the user of the materials it buys and pays the tax on them |
| Homes versus businesses | No difference. The rule looks at how you bill, not at the kind of building |
| New buildings versus repairs | No difference. The same materials rule applies to a new house and to a repair |
| Tax-exempt customers | Materials that go into a building owned by a government body, a charity or a public school can be bought tax-free with an exemption certificate from the Department of Revenue |
| Do you register to collect tax? | Only if you bill time and materials or sell parts over the counter. The state does not issue a sales tax license to a contractor who only quotes fixed prices |
| Tax rate | 2.9 percent state, plus city, county and special district rates that vary by address |
Checked by software against the official page
Getting paid
10Getting paid: lien and notice deadlines for a Colorado plumber What is this?
If you are not paid in Colorado, a lien on the property is your backstop, but only if your notice goes out on time: serve a notice of intent on the owner and on the main contractor at least ten days before you file the lien. To file on October 1 you serve it by September 21 at the latest. You file proof of that service together with the lien.
| Who has to send a notice | Everyone who wants to file a lien. Colorado has no notice at the start of a job, but nobody can file a lien without first serving a notice of intent |
|---|---|
| Send your notice by |
|
| File your lien by | Within four months after your last day of work or your last delivery (last day of work June 1 means you file by October 1). A worker claiming wages only has two months after the building is finished |
| File a lawsuit by | Within six months after your last day of work or the completion of the building (last day of work June 1 means you sue by December 1), and you file a notice of the lawsuit with the county clerk in the same window |
| What the owner can argue back | On a single-family home the owner lives in, or one the owner is building to live in, the owner can beat a subcontractor's lien by showing the main contractor was paid in full |
| Who can file a lien | Contractors, subcontractors, workers, suppliers, and the architects and engineers who drew the plans |
Checked by software against the official page
Keeping it
11How do you renew a plumbing license in Colorado? What is this?
The Plumbing Contractor registration renews every two years today, ending on the last day of February in odd-numbered years, with a sixty-day grace period and a late fee inside it. It becomes every three years for licenses issued or renewed on or after 1 March 2027.
| License | Renewal | Training hours each year |
|---|---|---|
| Residential Plumber | Every two years today, ending on the last day of February in odd-numbered years, with a sixty-day grace period and a late fee inside it. It becomes every three years for licenses issued or renewed on or after 1 March 2027 | — |
| Journeyman Plumber | Every two years today, ending on the last day of February in odd-numbered years, with a sixty-day grace period and a late fee inside it. It becomes every three years for licenses issued or renewed on or after 1 March 2027 | — |
| Master Plumber | Every two years today, ending on the last day of February in odd-numbered years, with a sixty-day grace period and a late fee inside it. It becomes every three years for licenses issued or renewed on or after 1 March 2027 | — |
| Plumbing Contractor registration | Every two years today, ending on the last day of February in odd-numbered years, with a sixty-day grace period and a late fee inside it. It becomes every three years for licenses issued or renewed on or after 1 March 2027 | — |
Renewal fees are in what the license costs. The official page for each license is linked under how you get it.
Watch out
12What catches people out in Colorado What is this?
The things people get wrong or do not expect about Colorado, in a few sentences.
- The license period is in the middle of changing. It is two years today and the current one ends on the last day of February 2027. Licenses issued or renewed from 1 March 2027 run three years.
- Colorado licenses the person and registers the business separately. To register a plumbing contractor you must be a master plumber or employ one full time, and that master can stand behind only one company.
- Since July 1, 2025 your registration number and your master's license number must be on your trucks, your bids, your bills and your website, in letters at least two inches tall.
- Training is counted by the month. You need eight hours of classes for every twelve months since your last renewal, so a three-year license means twenty-four hours.
- Colorado does not tax your labor. Quote a fixed price and you pay the tax on materials at the supply house. Bill time and materials and you must hold a sales tax license and charge tax on the marked-up parts.
- You cannot file a lien out of the blue. A notice of intent must reach the owner and the main contractor at least ten days before you file, and proof of that goes in with the lien.
- The plumbing law and the board rules name no liability insurance, yet the board guide tells a plumbing contractor to carry $300,000 of general liability and $100,000 of property damage cover. The state asks for no bond. Workers' comp is different. You must prove you comply before the board registers your company.
Checked by a person against the official page
13Where these numbers come from
The labels under each table are explained on how to read a page.
- leg.colorado.gov/bills/hb24-1344
- dpo.colorado.gov/Plumbing
- apps2.colorado.gov/dora/licensing/Lookup/LicenseLookup.aspx
- colorado.public.law/statutes/crs_title_12_article_155
- law.cornell.edu/regulations/colorado/department-700/division-720/3-CCR-720-1
- colorado.public.law/statutes/crs_12-155-121
- denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Community-Planning-and-Development/Contractor-Licensing/CL-Resources-and-Downloads/Fees-for-Contractor-Licenses-and-Supervisor-Certificates
- denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Community-Planning-and-Development/Contractor-Licensing/Contractor-Licenses/Apply-for-a-Contractor-License
- drive.google.com/file/d/1qj5xUjZrBCbTDkd7GdhQQY7qNnIx5xks/view
- dpo.colorado.gov/Plumbing/Applications
- colorado.public.law/statutes/crs_12-155-110
- law.cornell.edu/regulations/colorado/3-CCR-720-1.4
- law.cornell.edu/regulations/colorado/3-CCR-720-1.5
- colorado.public.law/statutes/crs_12-155-112
- law.cornell.edu/regulations/colorado/3-CCR-720-1.3
- colorado.public.law/statutes/crs_12-155-103
- colorado.public.law/statutes/crs_12-155-108
- leg.colorado.gov/bills/hb25-1077
- colorado.public.law/statutes/crs_8-40-203
- colorado.public.law/statutes/crs_8-44-101
- colorado.public.law/statutes/crs_8-41-202
- colorado.public.law/statutes/crs_8-43-409
- cdle.colorado.gov/dwc/employers/insurance-coverage
- cdle.colorado.gov/dwc/employers/independent-contractors-and-coverage-exemptions
- colorado.public.law/statutes/crs_12-155-109
- law.cornell.edu/regulations/colorado/3-CCR-720-1.7
- law.cornell.edu/regulations/colorado/title-1/agency-201/division-5
- colorado.public.law/statutes/crs_39-26-708
- colorado.public.law/statutes/crs_39-26-106
- tax.colorado.gov/sites/tax/files/documents/FYI_Sales6.pdf
- colorado.public.law/statutes/crs_38-22-109
- colorado.public.law/statutes/crs_38-22-110
- colorado.public.law/statutes/crs_38-22-102
- colorado.public.law/statutes/crs_38-22-101