How to Find a Reliable Plumber: 10 Things to Check

The UK has no licensing requirement for plumbers — anyone can call themselves a plumber and start work on your pipes. This creates a wide quality range, from excellent tradespeople to rogue traders who cause more damage than they fix. Here’s a practical checklist for finding someone reliable before you need them, not in the middle of an emergency.

1. Verify Gas Safe registration for any gas work

If any work involves gas pipes, gas appliances, or the boiler: the engineer must be Gas Safe registered. This is a legal requirement under the Gas Safety (Installation and Use) Regulations 1998. An unregistered person working on your gas supply is breaking the law; any work done is uninsured and invalid.

How to verify: Go to gassaferegister.co.uk, enter the engineer’s Gas Safe registration number (they should be able to provide it without being asked). Check that their registration covers the specific type of work you need (boiler service, gas pipe repair, etc.).

Gas Safe registration proves the engineer has been assessed as competent for specific types of gas work. It does not prove they’re a good plumber in general — but it’s the minimum legal requirement and a necessary starting point.

2. Check WaterSafe membership for water supply work

WaterSafe is a UK register of approved plumbers who have demonstrated competence in water regulations. Membership isn’t mandatory, but WaterSafe plumbers have been assessed by their professional body (typically the WRAS-approved route) and are required to comply with the Water Supply (Water Fittings) Regulations 1999.

Find WaterSafe members at watersafe.org.uk.

3. Ask for three references and call them

Any established plumber will have previous customers willing to vouch for their work. Ask for three recent references — recent enough that the work quality is still relevant — and call them. Specifically ask:

• Did the plumber arrive when they said they would?
• Was the price as quoted, or did it escalate?
• Was the work done cleanly and with minimal disruption?
• Did anything go wrong, and if so, how did the plumber handle it?

A plumber who can’t provide references isn’t established enough to be trusted with significant work.

4. Get at least two quotes for non-emergency work

For planned work — a new boiler, bathroom installation, drain survey, leak repair — get at least two written quotes from different contractors. Compare:

• What’s included (and what’s explicitly excluded)
• Whether VAT is included
• The scope of work specified
• Any warranty or guarantee offered

The cheapest quote isn’t always the best value, and a suspiciously cheap quote often precedes additional charges once work starts. The most expensive isn’t necessarily the best either. What you’re looking for is a quote that’s competitive, clearly specifies the work, and comes from someone whose references check out.

5. Demand a written quote before work starts

A verbal quote is difficult to enforce if the bill comes in higher. For any work costing over £100, ask for a written quote specifying:

• Scope of work
• Materials to be used
• Price (including VAT)
• What’s excluded
• Timeline
• Guarantee terms

This is your contract. Any contractor who refuses to put the price in writing is a risk.

6. Check for public liability insurance

If a plumber damages your property while working, their public liability insurance covers the cost. Ask for confirmation of cover — a card, certificate, or a policy number you can verify. A minimum of £1m public liability is standard for sole traders; larger firms typically carry £2m–£5m.

An uninsured plumber who floods your kitchen and causes structural damage is a very difficult situation — you’d need to pursue them personally for the cost, and if they have no assets, you may recover nothing.

7. Avoid the ‘cash in hand to avoid VAT’ offer

A plumber who offers a discount for cash payment is offering to evade VAT (or income tax). This creates problems for you:

• No receipt means no paper trail
• If they did the work without being VAT-registered, any contract for services worth over the VAT threshold is technically void
• If something goes wrong, you have no formal contract to enforce
• HMRC can in some circumstances pursue the customer as well as the contractor in deliberate tax evasion arrangements

Pay by bank transfer or card, get a VAT receipt. It’s cleaner for everyone.

8. Check that their vehicle and presentation matches the job

This isn’t about class — it’s about proportionality. A plumber who turns up in an unmarked van with no tools, or who can’t explain what they’re going to do in plain English, isn’t inspiring confidence. A marked vehicle, professional attire (clean work clothes, not necessarily uniform), and someone who asks questions about the job and explains their approach is far more reassuring.

9. For drainage: check CCTV capabilities

If you’re hiring a drainage contractor rather than a general plumber, ask specifically:

• Do you carry a CCTV camera? What make?
• Can you provide a written condition report?
• Is the report WinCan-compliant?
• Do you carry a jetting rig? What operating pressure?

A drainage contractor who only offers rodding (no jetter, no camera) is limited in what they can diagnose and treat. CCTV capability is the mark of a professional drainage contractor.

10. Trust your instincts — and don’t be pressured

If an engineer quotes an unexpectedly high price, tells you urgently that the work is an emergency requiring immediate decision, or discovers additional work after starting that doubles the bill: pause. Get a second opinion before agreeing to anything.

Legitimate contractors don’t use high-pressure sales tactics or manufacture urgency. If something feels wrong about how a contractor is operating, it probably is.

Where to find reliable tradespeople

• Gas Safe Register (gassaferegister.co.uk) — Gas Safe registered engineers by postcode
• WaterSafe (watersafe.org.uk) — approved plumbers
• Checkatrade, Trustpilot, MyBuilder — verified reviews, though not a substitute for checking credentials directly
• Recommendation from neighbours or local community — still one of the best sources
• Your home insurer’s emergency contractor network — for emergency work, your insurer’s approved contractors have vetted their credentials and are contracted to fair pricing