You finish a bathroom refit. Three days of graft, materials out of your own pocket, two trips to the merchant. You send the invoice and the customer pays without a peep. Sounds great — until you sit down and realise you made less per hour than the lad working the till at Screwfix.
It happens more than you'd think. Most plumbers who are undercharging don't even know they're doing it, because they've never properly broken down what a job actually costs them.
Day Rate vs Fixed Price — Which Is Better?
This is the big debate, and honestly, the answer is both. It depends on the job.
Day rates work well for reactive work where the scope is unpredictable. A leak investigation, for instance — you don't know if it's a dodgy fitting or a corroded pipe behind a wall until you get in there. Charging a day rate (or half-day) protects you from a two-hour job turning into an eight-hour nightmare.
Fixed pricing suits defined jobs where you know exactly what's involved. Tap replacements, radiator swaps, toilet installs — you've done them fifty times and you know how long they take. Fixed prices give the customer certainty, and they're usually happier to say yes when there's a clear number on the table.
The Real Cost of Doing a Job
Here's where most plumbers trip up. They think about the hours on site and forget everything else. Your price needs to cover:
Your time on site. The obvious one. But don't just count wrench time — include setup, cleanup, and testing.
Travel time and fuel. If a job's 40 minutes away, that's nearly an hour and a half of driving plus fuel. You need to charge for that. A plumber in Bristol told me he was driving 45 minutes each way to jobs in Bath and not adding a penny for travel. That's madness.
Materials and markup. You should be marking up materials by 15-25%. You're sourcing them, collecting them, carrying them in, and guaranteeing them. That's worth something. Don't feel guilty about it — every trade business does it.
Your overheads. Van payment, insurance, tools, fuel, phone, accountant, Gas Safe registration. Add all of that up for the year and divide by your working days. That's your daily overhead. If you're not covering it on every job, you're slowly going backwards.
Example Pricing for Common Jobs
These are rough guides for 2026 based on what decent plumbers are actually charging (not what customers wish they'd charge):
Tap replacement: £80-£120 for a straightforward swap, plus the cost of the tap. If isolators are missing or the fittings are seized, it's more.
Boiler service: £80-£100 for a gas boiler service. Takes about an hour once you're set up. Good bread-and-butter work, and it keeps your Gas Safe records tidy.
Radiator swap: £120-£180 depending on size and access. Draining down, removing the old one, fitting the new — it's half a day when you factor in testing and refilling.
Full bathroom refit: £2,500-£5,000 for labour on a standard bathroom. This varies massively depending on scope, but don't let anyone convince you that a full bathroom is a £1,500 job. If you're doing first fix, second fix, tiling, and waste — you're earning that money.
Stop Quoting on the Spot
One of the biggest pricing mistakes is giving numbers on the doorstep. The customer asks "how much?" and you blurt out a figure because you don't want to look unsure. Then you're locked in.
Instead, say: "Let me measure up and I'll get a quote to you this evening." That gives you time to price it properly — materials, time, travel, the lot. Tools like Gaffer can help you fire off professional quotes quickly once you've worked out the numbers, so the customer gets something in writing within hours rather than days.
The Undercharging Trap
Here's a scenario. Steve's a decent plumber in Leeds. He charges £200 a day because that's what his mate charges. But Steve's mate works from home and drives a paid-off van. Steve's got a £350/month van lease, £150/month insurance, and he drives further to jobs. Steve's actually netting about £120 a day after expenses. That's less than £15 an hour.
Steve's not lazy and he's not bad at his job. He just never did the maths. Don't be Steve.
How to Work Out Your Minimum Day Rate
Take your annual expenses — every business cost you have — and divide by 220 (roughly the number of working days in a year once you strip out weekends, holidays, and sick days). That's your break-even number. Your day rate needs to be well above that, because you won't be billable every single day. You'll have quoting days, admin days, quiet patches.
A good rule: your day rate should be at least double your daily overhead. If your overheads work out at £80/day, you need to be charging £250+ to make a proper living.
Confidence Is Half the Battle
The hardest part of pricing isn't the maths. It's the confidence. Saying "that'll be £350" and not immediately following it with "but I could do it for £280 if that's too much."
Good customers — the ones you actually want — will pay fair prices for good work. The ones who always want cheaper will grind you down on every job and leave you a three-star review anyway. Let your competitors have them.
Write clear, itemised quotes. Show the customer what they're getting. When the price is broken down — labour, materials, travel, VAT — it's much harder for them to argue with it. Some plumbers use tools like Gaffer to send itemised quotes over WhatsApp, which means the customer gets something professional-looking without you messing about with Word documents at 9pm.
Review Your Prices Every Six Months
Materials go up. Fuel goes up. Insurance goes up. If your prices haven't changed since 2024, you're earning less in real terms than you were two years ago. Set a reminder to review your rates in March and September every year. Bump them up in line with your costs at minimum.
Nobody ever lost a good customer over a £10 increase. And if they leave over £10, they weren't a good customer.