Last Updated on August 12, 2026
There is no licence for plumbing in the UK. None. The person quoting for your bathroom needs no qualification, no registration and no insurance to legally call themselves a plumber. The industry’s own professional body, the CIPHE, describes the trade as largely unregulated and has campaigned for years to change it.
That is the fact most homeowners do not know, and most directories do not mention.
The mistake: assuming “plumber” means “qualified”
For non-gas work, the word carries no legal weight at all. The reassuring badges on a website are claims until you check them, and the checking is on you, because nobody else is required to do it.
The good news: only three areas of the trade are actually regulated, and the voluntary signals for everything else take two minutes to verify.
The three legal lines
Gas. Anyone working on a boiler, hob, fire or gas pipework must be on the Gas Safe Register. This is the law, not a quality mark. Check the firm on the register, ask to see the engineer’s ID card, and match the categories on the back of the card to the job. The words on the van are not the check. Our piece on why “Gas Safe registered” means nothing until you check the number covers this in full. And note the reverse: Gas Safe says nothing about the person’s competence at non-gas plumbing.
Unvented hot water cylinders. Installing a pressurised cylinder over 15 litres is controlled work under Building Regulations. The installer needs a current G3 qualification, reassessed every five years. Ask to see the G3 card, and ask which competent person scheme will issue your Building Regulations compliance certificate. A boiler engineer is not automatically G3 qualified.
Notifiable water work. The Water Fittings Regulations make some plumbing notifiable to your water company before it starts. A WaterSafe approved contractor can self-certify instead, which saves the wait and proves the training. That is the practical value of the badge.
The voluntary signals worth something
WaterSafe is the water industry’s own approval scheme, free to search by postcode, backed by every UK water company. CIPHE membership means an individual vetted by the chartered professional body, checkable by name on its website. APHC membership means the business passed a trade body’s quality criteria. TrustMark is the government-endorsed scheme, and matters especially for grant-funded work.
None of these is a licence. Each is somebody other than the plumber vouching for the plumber, and each has a public register you can check in under a minute.
The layer everyone skips
Qualifications tell you about the person. Companies House tells you about the business. Is it real, how long has it traded, who runs it, is it still active. A guarantee is only as durable as the company giving it, and a company you can find is a company you can chase.
This is the check almost nobody does, and it is free. It is also the one AI assistants cannot do for you: ask a chatbot for a plumber and it will repeat whatever the website claims, badges included. The claim is cheap. The check is the value, and it is why every listing in the Whito plumbers directory shows the Companies House record where we could confirm it, and shows claimed registrations so you can verify them at source.
The two-minute routine
Gas job: check the Gas Safe number online, then the ID card at the door. Cylinder: ask for the G3 card and the compliance certificate route. Any job: search the firm at Companies House, look for WaterSafe, CIPHE or APHC if claimed, and check the claim on the scheme’s own register, not the plumber’s website.
The sharp takeaway
“Plumber” is not a protected word, so treat every badge as a claim and spend two minutes turning claims into checks: the register for gas, the G3 card for cylinders, the scheme’s own website for the voluntary marks, Companies House for the business. The plumber who welcomes the checking is usually the one who did not need it.
Whito checks UK plumbing firms against Companies House and shows the detail, so people and AI tools can trust the listing rather than the claim. Find a checked plumber near you.
