How to Invoice Plumbing Jobs

Invoice the service call before you leave

Plumbing service work (a stopped drain, a leaking supply line, a running toilet, a water heater that won't light) is usually diagnosed, approved, fixed and paid for in one visit. Present the invoice while the customer can still see the result: run the water, flush the toilet, show them the dry fitting and the flowing drain, and offer them the old part. Then take payment before you leave. Get approval for each task before you start (a flat-rate price, or your hourly rate and a time estimate), so the invoice only confirms what the customer already agreed to. Payment methods, terms and reminders are covered in how to get paid faster.

What goes on a plumbing service invoice

• Where the work was. The fixture or system and its location ("hall bath lavatory", "gas water heater in garage"), plus the unit number in a multi-unit building.
• The complaint and the cause, one plain sentence each: "Toilet running constantly. Flapper warped, fill valve leaking."
• The service-call or trip fee, and whether it was credited toward the repair under the policy the customer heard when they booked.
• Each task on its own line, flat rate or hours plus parts (see below).
• Access work. Where you opened drywall, a ceiling or flooring, how big the opening is, and whether patching is included. If it isn't, write "patch and finish by others".
• Existing conditions, such as a main shutoff that won't close fully, corroded valves or old galvanized pipe, so the record shows they were there before you.
• Recommendations the customer declined, such as a camera inspection or a pressure-reducing valve.
• Payment received and any balance.

Example: A weekday call for a slow kitchen drain. Service call: $90, credited toward approved work under your posted policy. Clear kitchen drain line through the cleanout, flat rate: $240. Total due: $240, paid by card before the tech leaves. Note on the invoice: "Heavy grease buildup about 15 feet from the sink. Recommended a camera inspection if the drain slows again; customer declined today." The prices are made up for illustration.

If the customer declines the repair, the invoice still shows the service-call fee and what you found. That written diagnosis is your record if someone else's fix doesn't hold.

When the person at the door isn't paying

A plumbing call can come from a tenant, and a leak in a condo or apartment can cross unit lines, so settle who pays before you open a wall. Put a property manager's work order number and any not-to-exceed amount on the invoice, and call before going over it. Get a landlord's approval of the price directly; the tenant signs only that the work was done. When one unit's water damages another, get the paying party named in writing, because owners, the association and tenants may each assume someone else is paying.

Emergency and after-hours lines

An after-hours charge holds up when the customer heard it before you were dispatched and sees it on the invoice under the same name. Put it on its own line, never folded into the repair, and record when they called, when you arrived and when the water was back on.

Plumbing emergencies have a feature many trades don't: closing a fixture stop or the main shutoff can often stop the damage without fixing anything. Offer the customer that choice and write down what they chose:

1. Shut the water off now and make the repair during regular hours at regular rates.
2. Make a temporary repair (cap or isolate the broken branch) so the rest of the house has water, and finish during regular hours.
3. Make the full repair now at after-hours rates.

Bill the emergency visit and the permanent repair on separate invoices, so the premium attaches only to the work that had to happen at night.

Example: At 9 p.m. on a January Saturday, a copper line splits in an unheated crawlspace. On the phone, the customer hears your after-hours dispatch fee ($200 here). On site, they choose a temporary cap tonight and the repair on Monday. Saturday's invoice: after-hours dispatch, $200; isolate and cap the damaged branch, $150. Monday's invoice: replace the damaged section and insulate the line, flat rate, $380, no premium. Both invoices note the customer's choice and the times. The prices are made up for illustration.

Before the next night call, also decide:

• Permits. If emergency work needs a permit, such as a water heater replaced on a weekend, ask your building department how it handles that, and show the status on the invoice ("permit applied for", with the date).
• Declared emergencies. After a declared emergency such as a hard freeze or a flood, check your state attorney general's guidance on pricing before you raise rates.

Setting the premium, trip fees and flat-rate prices is covered in how to price plumbing jobs.

Flat-rate and hourly invoices show parts differently

How you priced the job decides how the invoice reads. Don't mix the formats: a flat-rate task with its parts also listed at a price looks like you charged for them twice.

Flat-rate invoices

A flat-rate line is the price of an installed result, so the parts are inside it. Show the task name from your price book with one line on what it includes ("Replace kitchen faucet: includes two new supply lines and disposal of the old faucet"), then the parts installed, by brand and model, without separate prices. The next plumber needs to know what's in the wall; the customer doesn't need a second price for it. An added task, like a shutoff valve that crumbles when you turn it, gets its own flat-rate line, approved before you do it.

That description also answers a customer comparing your faucet line with a home center's shelf price: you're charging for an installed, warranted faucet, not the box.

Hourly invoices

On a time and materials invoice, show enough to check the hours and parts:

• Arrival and departure times, and the hours billed.
• Your hourly rate, plus drive time or a minimum charge if your terms include them.
• Each part with quantity and unit price, down to fittings and lengths of pipe.
• Consumables (solder, flux, primer and cement, thread sealant) as one shop-supplies line or built into your parts markup. Pick one and say which on your rate sheet.
• Disposal or haul-away as its own line.

Water heater replacements

Customers pull out a water heater invoice again when the tank leaks or the house sells, so list the heater's make, model, serial number, capacity and fuel type. Give each separately priced item its own line: an expansion tank or drain pan where your local code required one, venting changes, gas or electrical work, the permit and haul-away.

Example: A 50-gallon gas water heater replacement priced from a flat-rate book. Line 1: "Replace 50-gallon gas water heater, standard installation," $2,600, with make, model and serial number and a note of what the price includes (connections, venting, relief valve discharge pipe, haul-away). Line 2: "Thermal expansion tank, required by local code on this job," $300. Line 3: "Permit, passed through at cost," $75, with the permit number and "inspection scheduled." Total: $2,975. The prices are made up for illustration.

Put the warranty terms on the invoice

The invoice is the document the customer keeps, so write your warranty there in plain words. Your workmanship warranty covers your labor; the manufacturer's warranty covers its product under its own terms. Say which is which, and for yours, state:

• Length and coverage. "Leaks at connections we made" is clearer than "all work guaranteed".
• Exclusions. Consider freeze damage, clogs from what goes down the drain after you leave, problems from water pressure the customer chose not to correct (note the declined pressure-reducing valve), customer-supplied fixtures and existing piping you didn't replace.
• How to make a claim. Who to call, and that you need to see the problem before anyone else repairs it.

Water damage is what makes plumbing warranties different: one failed connection can soak floors, ceilings and belongings. Whether your terms can limit your responsibility for that is a question for a lawyer, so have one review your warranty wording once.

Drain cleaning guarantees

Tie the guarantee to the line you cleared and a time window you choose, and write what voids it. Roots through a broken joint, a sag that holds water or a collapsed section on camera means clearing bought time but didn't repair the pipe. Put that finding next to the guarantee on the invoice.

Equipment and customer-supplied fixtures

For water heaters, tankless units, softeners and sump pumps, record the make, model and serial number, and read each manufacturer's warranty for registration requirements, installation conditions and owner maintenance such as flushing or descaling. Write on the invoice what you registered (or that the homeowner will) and what maintenance keeps the coverage in force.

When the customer supplies the fixture (a faucet or toilet they bought online, say), write "customer-supplied" next to its model, and state that your warranty covers the installation only, that product problems go to the seller or manufacturer, and that a return visit caused by a defective fixture is billable.

Photos and camera footage

Most of what a plumber fixes ends up behind drywall, under a slab or underground, so photos are the invoice's proof. Attach them and caption each one with the line it supports.

• Before: the failure in place, the failed part once removed, data plates on equipment you're replacing, and existing conditions you didn't cause.
• During: anything about to be covered, such as new piping in an open wall or a trench before backfill.
• After: finished connections, dry; new equipment showing each invoiced item; the drain running.
• Camera work: save the video, note the distance from the access point for each finding (roots, offset joints, sags, breaks), put stills of the key findings on the invoice and give the customer a copy. The same footage belongs in your estimate for the repair that follows; see how to write a plumbing estimate.

If there's water damage, the homeowner may need your invoice and photos for an insurance claim. Describe the cause plainly ("dishwasher supply line split at the compression fitting") and leave coverage questions to the homeowner and their insurer.

Progress billing for repipes, remodels and new construction

On bigger jobs, bill in stages tied to work someone else can confirm, such as an inspection passed, a pressure test witnessed or fixtures set, rather than calendar dates that drift with drywall and tile schedules.

• Repipe: materials and start; new piping installed and pressure tested (and the rough inspection passed, if the job has one); fixtures reconnected and the final inspection passed.
• Remodel or new construction: underground or under-slab work where there's a slab; rough-in; trim, with fixtures set and the final inspection passed.

Put the stages and amounts in the contract. Each progress invoice shows the stage reached, its amount, payments received so far and the remaining balance. Deposits, including any limits your state puts on them, are covered in how much deposit to ask for.

Example: A whole-house repipe sold at $12,000. The contract schedule: $2,000 at signing for materials (where your state allows a deposit that size), $6,000 when the new piping is installed, pressure tested and passes rough inspection, and $4,000 when fixtures are reconnected and the final inspection passes. With a wall open, the crew finds the main shutoff badly corroded, and the customer approves a $300 change order in writing before it's replaced. The final invoice shows the $4,000 stage, the $300 change order and the $8,000 already paid, for $4,300 due. The numbers are made up for illustration.

Two things move the final number off the contract price:

• Fixture allowances. Show the allowance, the actual price of what the customer chose and the difference, up or down.
• Concealed conditions. Rotted subfloor under a toilet, a cracked drain behind tile, old pipe that falls apart when you cut into it. Each becomes a written change order, approved before the work and invoiced on its own line, as how to handle change orders explains.

Under a general contractor, bill the GC's way (their pay application format, billing dates and any retainage held until completion), and track retainage as money still owed to you.

Lien rights and preliminary notices

A mechanic's lien can secure payment on a larger job, but only if you protect the right to file one, and each state sets its own rules. Some states require a written notice, such as a preliminary notice, before you can file a lien, with its own deadline and delivery rules. Your role can matter too. California is one example: a subcontractor or supplier has 20 days after starting work or delivering materials to serve a preliminary notice, a late notice covers only work done from 20 days before it was delivered, and direct contractors who contract with the owner don't have to send one ¹. So in California, a plumber hired by the homeowner for a repipe and the same plumber working under a general contractor on a new house have different duties. That's one state's rule; check yours before work starts, through your state's statutes, your contractor licensing board or a construction attorney.

Then build the deadlines into each job:

1. At signing, note whether this job needs a notice, who must receive it and by when, and put that date on the job calendar.
2. Send the notice the way the law requires and keep proof of delivery in the job file.
3. If your state requires lien wording in residential contracts, use the wording it prescribes.
4. Track the deadline for recording a lien too. Missing it can end the lien right even if the notice went out on time.

When you're paid, you may be asked for a lien waiver, especially on GC-led jobs and jobs with a lender. Use your state's form if it has one, and don't sign an unconditional waiver until the payment has cleared. A lien is a last resort: the reminder sequence, payment plans and when to involve an attorney are in how to collect overdue invoices, and lien basics are in mechanic's lien.

Before a plumbing invoice goes out

• Fixture or system, location, complaint and cause named.
• Every line matches an approved flat-rate task, your hourly terms or a signed change order.
• Any after-hours charge on its own line, as quoted, with times.
• Parts by brand and model, with prices only on hourly invoices.
• Access openings, existing conditions and declined recommendations noted.
• Warranty terms stated and serial numbers recorded.
• Photos and camera stills attached and captioned.
• Permit number and inspection status listed.
• Progress invoices show the stage, payments, change orders and balance.
• Lien notice deadlines checked where they apply.