Is flat-rate pricing better than hourly?

Neither is better in general. A flat rate tells you the price before work starts, but it includes the company's estimate of time, overhead and risk. Hourly suits jobs where nobody knows the scope until the work begins. We found no independent study of which costs homeowners less.

What is a trip charge or diagnostic fee?

It is a charge for coming to your home and finding the problem. Housecall Pro, a software vendor, says it may also be called a service call, dispatch or diagnostic fee. Consumers' Checkbook found some Puget Sound companies charge nothing for a visit, diagnosis and written quote, while others charge $200 or more.

Is the diagnostic fee credited toward the repair?

Sometimes. Smart Service, a software vendor, calls crediting the fee when the customer approves the repair on the same visit the most common practice, but it is a company policy, not a rule. Ask before the technician is dispatched and get the answer in writing.

How much more do plumbers charge after hours?

There is no Washington survey. Two software vendors give 2026 national conventions: Housecall Pro says after-hours work is often 1.5 to 3 times the standard hourly rate, and Smart Service says 1.5 times for evenings and 2 times for weekends and holidays is standard. Ask for the exact charge before you book.

Are plumbing membership plans worth it?

It depends on what you would use. Add up what the included visits and discounts would cost you at regular prices and compare that with the yearly fee. Check how the plan renews and how to cancel. We found no independent evaluation of plumbing plans.

How do I compare quotes from plumbers who price differently?

Give each company the same written description of the job, and ask each to list scope, parts, warranty, permit and taxes separately. For an hourly bid, ask for the rate and the expected hours. L&I advises getting bids in writing from several registered contractors.

How plumbers price: flat rate vs hourly, trip fees and memberships

Two plumbers can quote the same job in completely different ways: one gives a single price, the other an hourly rate plus parts. Consumers’ Checkbook’s Puget Sound survey found that “prices varied dramatically for the same work”. Knowing how each price is built makes the quotes comparable.

A note on sources. Most of what’s published about how plumbers price comes from companies that sell scheduling and pricing software to contractors (ServiceTitan, Housecall Pro, Smart Service). They write for plumbers, not homeowners. We use them to explain how contractors are coached to price, and label them where we do. We found no independent study comparing what homeowners pay under each model.

ServiceTitan describes flat-rate pricing as charging “a set price for a specific job, regardless of how many hours it takes”. It says the price covers parts, labor and overhead. Its example: a $250 flat rate to fix a leaky faucet that includes parts, estimated time, and overhead such as fuel, truck maintenance and insurance.

Companies keep these prices in a price book. Housecall Pro says flat rates work best “for repeatable jobs where your team knows the average labor time, materials, and risk”. Some companies present options at several levels; one plumber quoted by Housecall Pro offers “minimum, complete, and premium” packages.

For you:

You know the price before work starts, and it doesn’t rise if the job runs long.
It also doesn’t fall if the job is quick. The company’s estimate of time and risk is built in.
The scope wording decides what you get. Ask exactly what’s included: removal and disposal of the old fixture, new supply lines or shutoff valves, cleanup, and permit.
If there are package options, ask what the cheapest one leaves out and whether it fixes the problem.

Time and materials (hourly)

Hourly or time-and-materials pricing charges for parts plus labor time, according to ServiceTitan. Housecall Pro says hourly pricing “works best when you don’t know exactly what the job will take until you’re on-site”, and that many plumbing businesses use a mix of both.

For you:

Ask for the hourly rate, the minimum charge, how time is counted (from dispatch, or from arrival), and the parts markup if any.
Ask for an estimate of hours and a not-to-exceed figure, with a call before going over it.
Checkbook’s ratings list each firm’s hourly rate and minimum service-call charge, which helps you compare.

Trip, service-call and diagnostic fees

Housecall Pro says a service call fee “covers the cost of traveling to the customer’s property”, and may also be called a diagnostic fee, dispatch fee or trip charge. Some companies fold travel into their labor rate instead.

Checkbook found that “some companies don’t charge anything for coming to your home, diagnosing the problem, and providing a written price quote; others charge $200 or more for this.” Smart Service (a software vendor) says a “meaningful share” of residential plumbers charge no trip fee, and that crediting the fee when the customer approves the repair the same day is “the most common practice”. Neither is guaranteed.

Ask on the phone:

Is there a trip or diagnostic fee, and how much?
Is it credited toward the repair if I go ahead? Only the same day?
Does the visit include a written quote I can take to another company?

After-hours and emergency charges

We found no Washington survey of after-hours premiums. Software vendors describe common conventions (national, 2026):

Housecall Pro: after-hours, holiday or emergency work is “often 1.5–3x the standard hourly rate”, and an emergency dispatch fee is usually separate from the repair.
Smart Service: 1.5 times the normal rate for evenings and 2 times for weekends and holidays, with some businesses adding a fixed emergency premium.

If the problem can be contained (water shut off, fixture isolated), ask what the same repair would cost during regular hours. Get the after-hours charge confirmed before the technician comes.

Membership and maintenance plans

Some companies sell yearly maintenance plans that include a visit and discounts on service. Housecall Pro tells contractors a simple residential plan “might start around $100 per year”, priced to cover the visit, admin time and the discounts included. In other words, the discount is paid for in the fee.

Before you sign up:

Add up what you would actually use in a year (visits, discounts on likely repairs) at the regular price, and compare it with the fee.
Ask whether it renews automatically, and how to cancel.
A discount off a higher price can still cost more than another company’s regular price. Compare quotes as a non-member too.

Upsells and add-ons

Trade publications openly coach selling on service calls. A 2006 Contractor magazine column on water heaters is titled “Sell hot water; don’t sell water heaters” and says better selling could raise a typical ticket from about $200 to $600–$700.

Some add-ons are required. King County, for example, requires seismic straps on water heaters and an expansion tank on closed water systems. Others are optional. To tell the difference:

Ask which code section or problem the add-on addresses, and for the evidence: a pressure reading, photos, or camera video with distance markings.
Ask for each add-on to be priced as a separate line.
For anything costly that isn’t an emergency, get a second quote. Take the evidence with you.

Getting quotes you can compare

Describe the job the same way to every company, in writing if you can: what’s wrong, where, and any photos or model numbers.
Ask for the same breakdown: scope, parts (brand and model), labor, permit, warranty on parts and on labor, and sales tax. WAC 458-20-170 says contractors collect retail sales tax on the full contract price for consumers.
Turn hourly bids into a number: rate × expected hours + parts, with a cap.
Check the contractor. L&I advises interviewing several registered contractors and getting bids in writing. Verify registration, bond and the plumber’s certificate with L&I’s Verify tool.
Get the paperwork. For residential jobs of $1,000 or more, RCW 18.27.114 requires the contractor to give you a lien disclosure statement before starting. L&I advises paying by completed phase, not up front, beyond a reasonable down payment.

L&I lists a contractor asking you to get the permit, or not providing a written contract or complete bid, as warning signs.

For water heater jobs specifically, see comparing water heater replacement quotes. To find licensed plumbers, browse the plumbing directory.