Which plumbers in Guildford do AI assistants actually recommend?

We put the 14 questions a person in Guildford asks before choosing plumber — cost, specialism, who to use, how to check them — to Claude and ChatGPT, 5 times each, 140 answers in all, and recorded every firm the answers named. 30 firms in Guildford were checked against those answers. 11 of them were named at least once. The rest were not recommended in a single answer.

The league table

Firms are ranked by the number of answers that named them, then by how many different questions. The assistants do not give identical answers twice, so a difference of one or two mentions is noise; being named on questions a rival is absent from is not.

The questions we asked

1. Do I need a plumber or can I fix a dripping tap myself?
2. How much does it cost to hire a plumber near Guildford for a boiler service?
3. Is it cheaper to get an annual maintenance contract or just call someone as and when things break?
4. What's better for an emergency leak, a local independent plumber near Godalming or a big national callout firm?
5. Should I choose a small independent plumbing firm in Guildford over one of the bigger chains for a bathroom refit?
6. My boiler's making a banging noise and I live just off the A25 near Bramley, who should I call that isn't a national brand?
7. We're moving into a new build in Ash and need someone local to check all the plumbing before we settle in, any recommendations?
8. How do I check if a plumber is Gas Safe registered before letting them into my house near Farnham?
9. What accreditations should an independent plumber in Surrey actually have to be trustworthy?
10. Are online reviews for local plumbers around Cranleigh reliable or mostly fake?
11. Which supplier or plumber should I use for a full central heating system replacement?
12. Which local plumbing company should I contact for a burst pipe emergency near Guildford?
13. Which independent plumber would you recommend between one based near Woking and one nearer Guildford for a bathroom installation?
14. Which locally recommended plumber near Guildford has the best reputation for reliability and turning up on time?

How this was measured

• Date: 23 September 2026. This is one day, not a trend; the index is re-measured monthly.
• Sample: 14 questions × 2 assistants × 5 runs = 140 answers. 30 firms checked.
• Assistants used: Claude (Anthropic’s Sonnet model, through its API, with web search); ChatGPT (OpenAI’s gpt-4o-mini model, through its API, with web search — not the model inside the ChatGPT app). Answers from these programming interfaces can differ from what the consumer apps show.
• Counting: a firm is counted when its name appears in an answer. Names are picked out of the answer text automatically, then matched to the firm list.
• Limits: the assistants vary between runs, so small gaps are noise. Firms that were not named may still be recommended by an assistant or a question we did not ask. National chains are left off the list.