Fixed-price or hourly?

Fixed-price for defined jobs. Hourly for diagnostic and active-leak work.

Compare · Updated May 2026

Compare Plumbers: How to Choose One in 2026 (UK)

Q: Gas Safe vs WaterSafe?

Gas Safe for any gas work. WaterSafe for mains and backflow. Most quality plumbers carry both.

Q: How do I check Gas Safe registration?

Ask for the engineer ID card and look up the number on gassaferegister.co.uk.

Q: Online platforms or local trader?

Vetted platforms cut search time and surface review depth fast.

Q: What if they want cash only?

Walk. Cash-only with no invoice loses all warranty and complaint routes.

Q: How much deposit is reasonable?

Materials-only deposit (25-40%) on bigger jobs. Full upfront is a red flag.

Choosing the right UK plumber in 2026 comes down to four checks: credentials (Gas Safe for any gas work, WaterSafe for mains, no exceptions), quote shape (fixed-price for defined jobs, hourly for diagnostic), insurance (£2m public liability minimum) and review depth (50+ verified reviews, not 5). Online lead-generation platforms can drop you straight onto a vetted shortlist or onto an unvetted contact-buyer farm — the difference matters. This guide walks the eight must-ask questions before you book, and the four red flags that should make you cancel even after the visit.

4 credential checks 8 must-ask questions 4 red flags

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Researched, written & fact-checked. Reviewed 18 May 2026. How we research & fact-check

Selection Checklist

Six Filters to Apply Before You Book

1. Confirm credentials

Gas Safe number on the gov register for any gas appliance work. WaterSafe for mains and backflow. No exceptions — even for "just a quick look".

2. Match quote shape to job

Fixed-price for replacement, refit and known-spec jobs. Hourly for diagnostic, leak-tracing and unknown-scope work.

3. Verify insurance & warranty

£2m public liability minimum. 12-month workmanship warranty as standard. Anything less, walk.

4. Read 50+ reviews, not 5

Shallow review counts hide trade-only complaints. Real depth (50-500 reviews on a vetted platform) gives the true picture.

5. Use a vetted platform

Look for proof of vetting (criminal record check, Gas Safe verified, insurance held). Unvetted lead-buyer farms reduce trust and quality.

6. Get 3 written quotes

Always 3 quotes. Spread typically £300-£600 on like-for-like spec. Verbal-only quotes are a red flag.

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Frequently Asked

Common Questions

Gas Safe vs WaterSafe — do I need both?+

Gas Safe for any gas appliance or pipework. WaterSafe for mains water and backflow risk. Most quality plumbers carry both.

How do I check Gas Safe registration?+

Ask for the engineer ID card. Look up the number on gassaferegister.co.uk. Both engineer AND business must be registered.

Online platforms or local trader?+

Vetted online platforms cut the search time and surface review-depth fast. Direct trade can be cheaper but takes longer to vet.

What is a fair fixed-price quote vs hourly?+

Fixed-price for defined jobs (refit, swap). Hourly for diagnostic or active-leak work where the scope only becomes clear once they have started.

What if they want cash only?+

Walk. Cash-only no-VAT-receipt jobs lose all warranty protection and complaint routes. Get an invoice for everything.

How much deposit is reasonable?+

Materials-only deposit (25-40%) on bigger jobs is normal. Full upfront payment is a red flag.

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