How to Start a Plumbing Business

Choose the work you'll start with

Decide what kind of plumbing you'll sell before you buy a van or a drain machine. The mix changes which licenses you need, what you stock, how you're insured and how fast cash comes back. Pick one or two to start:

• Service and repair: leaks, fixtures, toilets, shutoff valves and water heater repairs for homeowners. Small tickets paid at completion, a van full of parts and a phone that has to be answered.
• Drain and sewer: sink stoppages through mainline clogs and sewer line repairs. You'll need drain machines and, for mainlines, a camera; any digging adds trench safety and underground utility marking to the job.
• Water heaters: replacements are heavy, often urgent and, in many towns, permitted and inspected.
• Remodel and repipe: scoped work with written estimates, fixture allowances and change orders, sometimes under a general contractor.
• New construction: rough-in and trim-out for builders, billed in stages on the builder's schedule.
• Light commercial service: restaurants, offices and property managers who ask for certificates of insurance and may have backflow assemblies that need testing.

A solo plumber with one van can start in service and repair on less cash than new construction needs, because homeowners pay at completion and there's no builder's draw schedule to float.

Map the license ladder in your state

Your license decides what work you can sell, whether you can pull permits and whether you can run the company at all. BLS notes that most states require plumbers to be licensed, and that states and localities often require 2 to 5 years of experience and a passed exam before a plumber may work independently ¹. The details are set state by state, and in some places cities or counties license plumbers too, or instead. Start with your state's plumbing licensing board (in some states it's part of a broader licensing agency).

Where a state licenses individual plumbers, the ladder commonly has three steps. Titles, required hours and exams differ:

The business may need a license of its own. Depending on the state, a plumbing company may need a contractor license, a registration that names a licensed master as the responsible person, or nothing beyond the owner's individual license. Ask the board, and get the answers in writing:

• Which license lets you contract with homeowners and pull permits, and does the company need its own license or a named master?
• If you hold a journeyman license, what does the master license require, and do your current hours count toward it?
• Are gas piping, backflow testing, medical gas and fire sprinkler work covered by your plumbing license, or do they need separate licenses or endorsements?
• Does drain cleaning, water heater replacement or sewer line work require a plumbing license on its own?
• What insurance, bond or other proof keeps the license active?
• How many apprentices may each licensed plumber supervise? The plumbing hiring guide covers supervision and apprenticeships when you're ready to add people.
• What continuing education does renewal require, and how often do you renew?
• If you work near a state line, does the neighboring state accept your license?

Then ask the building or plumbing department in each city or county you'll serve whether it requires its own license or contractor registration before you can pull a permit there.

Learn the code and permit rules in each town

You'll be inspected against the plumbing code your jurisdiction has adopted, which may not be the newest edition or the one you trained under. Many jurisdictions base their rules on one of two model codes, the International Plumbing Code (IPC) or the Uniform Plumbing Code (UPC), while others use a state-written code or a different model. Each adopts a specific edition and often amends it, so neighboring towns can enforce different rules.

For each jurisdiction you'll work in, find out:

• Which code and edition it enforces, and where to get its local amendments
• Whether it plans to adopt a newer edition soon, so a change doesn't land in the middle of a job
• Which jobs need a permit: water heater replacements, repipes, sewer line replacements, added or moved fixtures, gas piping
• Who may pull the permit, how inspections are scheduled and what the inspector expects on site, such as a test on new piping or open access to the work

Buy the adopted edition for the places you work most and keep the amendments with it. Then learn how it treats the items that drive your prices: water heater details (expansion tanks, drain pans, relief valve discharge, venting and strapping where required), approved pipe materials and joining methods, venting options, cleanouts and fixture sizing.

Code also decides what a "simple swap" becomes. Depending on the jurisdiction, replacing a water heater or a fixture can require bringing related parts of the installation up to current code. Put that possibility in writing before you start: the plumbing estimate guide shows how to list code upgrades and exclusions, and how to price plumbing jobs prices a water heater replacement with the code items around the tank.

Insure for water damage, not just injuries

Plumbing's signature risk is water. A fitting that lets go, a supply line left loose or a drain that backs up after a repair can soak floors, ceilings and cabinets after you've gone home. Get quotes before you set prices, because premiums are part of every hour you sell.

General liability

General liability covers claims from third parties for bodily injury and property damage. Ask the agent plumbing questions:

• How are leaks that show up days or months after the job handled, and what limit applies to completed work?
• Is damage to the part of the house you worked on treated differently from damage to the rest of the house?
• Are mold, sewage and slow leaks excluded or limited?
• Are gas piping, excavation and sewer work covered, if you'll do them?
• What limits do the property managers and commercial clients you want require on a certificate of insurance?

Workers' compensation

State law decides when you must carry workers' compensation, so check your state's rules before you hire. Crawl spaces, trenches, torches, sewage and water heaters carried down basement stairs make plumbing hard on bodies, so get a quote on your expected payroll early and fold it into your labor cost, as how to set your labor rate explains.

Vehicle, tools and stock

Insure the van for business use and ask what covers tools and stock stolen from it. Copper, press tools and a sewer camera are expensive to replace and attractive to thieves, so ask whether high-value tools need to be listed on the policy.

Bonds

Ask your state board and each building department whether you need a contractor license bond to hold a license or pull plumbing permits. A bond protects consumers, not you: if the surety pays a claim, it will usually expect you to pay it back. It doesn't replace insurance.

Stock the van to finish on the first visit

For a service plumber, the van is the warehouse, and its job is to let you finish most repairs on the first visit. A mid-job run to the supply house burns time you usually can't bill at full rate and pushes every later call back.

Example: Suppose a missing part turns into a 90-minute round trip to the supply house, and an hour of your time costs $100 to deliver once overhead is counted (made-up numbers; work out your own). The trip costs about $150 in time, plus a late start on the next call. Carrying the part would only have tied up what it cost you.

Build the stock list from your calls, not from a catalog:

• Carry what fails most in your area. For residential service that typically means toilet repair parts (fill valves, flappers, wax rings, closet bolts), cartridges for the faucet brands common locally, supply lines and stop valves, P-traps and tubular parts, ball valves, fittings for the pipe you work on, and water heater parts such as thermocouples, elements, thermostats, relief valves and anode rods.
• Standardize your pipe systems. Choose the PEX connection method and fitting systems (crimp, expansion or press) you'll use and carry only those. Every extra system adds tools, bins and chances to grab the wrong part.
• Set minimums and restock on a schedule. Label bins, set a minimum count for each part and restock daily or weekly. Record parts on every job ticket so the restock list writes itself and job costing shows what each job used.
• Decide on the big items. A common size of water heater, a toilet or a sump pump on board lets you replace the same day but eats space and payload. Check the van's payload rating against shelving, stock, tools and pipe, and ask the supply house about will-call and job site delivery for the rest.
• Keep drinking water parts clean. Buy anything that touches potable water new, check that it's rated for drinking water, and keep salvaged parts out of the bins.

Open trade accounts at one or two plumbing supply houses before your first early call. Ask about counter hours, delivery, returns, restocking fees and credit terms, and ask your accountant how sales tax applies to the parts you install, since states treat it differently. Stock on the van is cash on a shelf, so your parts pricing has to cover shrinkage, restocking trips and warranty returns; the pricing guide covers parts markup.

Decide whether you'll take emergency calls

Plumbing emergencies don't keep business hours: a burst pipe, sewage backing into a basement, a water heater leaking through a ceiling. Whether you answer them shapes your pricing, your phone setup and your mornings, so decide before you advertise. A website that says "24/7" is a promise.

• Business hours only. The simplest to run. Say so on your website and voicemail, give callers shutoff instructions, and consider referring after-hours calls to a shop you trust.
• Extended hours. Evenings and Saturdays, with overnight calls left to others. A workable middle ground while you're solo.
• Around the clock. After-hours rates can make these calls worth taking, but someone has to answer every time, and a 2 a.m. call makes you late for the 8 a.m. one.

If you take emergencies, put after-hours and emergency rates in your price book and quote them before you dispatch. Give whoever answers the phone a short triage script:

1. Is water still running? Walk the caller to the fixture shutoff or the main shutoff.
2. Is water near outlets, the electrical panel or appliances? Tell them to stay out of it.
3. Is sewage backing up? Ask them to stop running water and flushing until you arrive.
4. Do they smell gas? Safety comes before scheduling: tell them to follow their gas utility's emergency instructions before anything else.
5. Can they text photos or a video? You'll bring the right parts and give a better price range.

An emergency call can be a customer's first contact with your shop, and a caller with water on the floor is unlikely to wait for a callback. The plumbing customers guide covers phone coverage and local search for urgent calls.

Add backflow testing when the numbers work

A backflow preventer keeps contaminated water from flowing back into the drinking water supply. Plumbing codes and water utility or state cross-connection control programs decide where testable assemblies go (irrigation systems, fire sprinkler connections and many commercial buildings are common examples), and local rules set how often they must be tested. For a service plumber, that testing can add short, schedulable visits, repeat customers and repair work when an assembly fails.

The rules for testers are local, so ask your state program or water utility before you spend money:

• Who certifies testers: the state, the water utility or a training program the utility recognizes?
• Does a tester need a plumbing license, or is tester certification separate?
• Does each water utility keep its own list of approved testers, and how do you get on it?
• What test kit is required, and how often must it be calibrated?
• How are results reported, on what form and by what deadline?
• Can a tester repair or replace a failed assembly, or does that need a licensed plumber and a permit?

Example: Suppose training, the exam and a test kit cost you $2,400, and you charge $100 per test with $40 of labor, drive time and paperwork in each one (all made-up figures; use your own quotes). Each test contributes $60, so 40 tests earn back the startup cost. Testing several assemblies at one commercial property cuts the drive time per test and pays it back sooner.

If the utility notifies owners when tests are due and publishes its tester list, a spot on that list works like free advertising. Ask how it's done where you are.

Budget by category

Startup costs depend on the work you chose first. Service and repair needs a van, tools and stock; drain and sewer, new construction and backflow testing each add equipment or cash needs. Get quotes in your market for each line:

Startup checklist

1. Choose the work you'll start with.
2. Get your state's license answers in writing, including what the company itself needs.
3. Check local licensing and registration in each city or county.
4. Learn each jurisdiction's adopted code, amendments and permit process, and buy the code book.
5. Form the business, get insurance and any required bond, and build premiums into your labor cost.
6. Open one or two supply house accounts and set up the van, stock list and restocking routine.
7. Set your emergency hours, after-hours rates and phone triage script.
8. Add backflow testing once the local rules and your numbers support it.