Ten prompts cover the messages a plumber writes most: a text for a missed call, a voicemail turned into a call-back plan, a return-visit offer, four quote prompts (a small fixed price, a choice of options, an emergency call-out price and a reply to a cheaper rival), and three complaint replies. Each has a filled example and a pass mark.
Plumbing messages carry two risks that general prompt lists skip: safety wording and promises about leaks. So every prompt here makes you supply your own emergency instructions and workmanship rules, and ChatGPT only places them. Nothing below asks it to diagnose a fault, size equipment or say what a regulation allows.
What never goes into ChatGPT, and what to paste instead
A chat is not a private notebook. It is a service run by a company, and what you paste stays in your account history until you delete it; OpenAI's help centre says deleted chats are removed from its systems within 30 days. On personal plans the model-training switch in the data controls decides whether your chats can be used to improve the model, and business plans do not train on workspace content by default. The tutorial on free, Plus or Business for plumbers covers which plan to pick. Whatever the plan, the safest habit is to paste the job, not the person.
| Do not paste | Paste this instead | Why it still works |
|---|---|---|
| The customer's name | [first name] or "the customer" | A reply needs a greeting, not an identity. |
| The street address | The type of property and the room, such as "two-bed flat, upstairs bathroom" | Quotes and messages depend on the job, not the street. |
| Phone number or email address | Nothing | Replies go out from your own phone or inbox. |
| Gate codes, key-safe numbers, alarm details | "Access details to be given by phone" | These should never sit in a chat history. |
| Card or bank details, invoice scans | The amount and "paid by card" | Payment data has no place in a prompt. |
| Photos showing faces, documents or meter numbers | A written description of what the photo shows | The description is all the draft can use anyway. |
Two more things stay out. Negotiated supplier prices and trade discounts belong in your costing sheet, not in a chat. And once a dispute involves a solicitor's letter, an insurer or a regulator, stop drafting with ChatGPT and take advice. The messages in this tutorial are for ordinary complaints, not formal claims.
A house-rules block to paste above every prompt
Plumbing messages need three pieces of wording that must never be improvised: what to do in an emergency, how to stop the water, and what your workmanship guarantee really says. Write them once, in your own words, and put them in a ChatGPT Project's instructions (Projects work on every plan), or paste the block above the prompt. ChatGPT then copies them instead of inventing them.
HOUSE RULES (apply to everything below)
Firm: [firm name], [number] plumbers. British English, plain and polite, no exclamation marks.
Emergency wording (copy exactly, never paraphrase): [your own words for a gas smell, flooding near electrics, or water you cannot stop]
Stop-the-water wording (copy exactly): [your own words for finding and closing the main stop valve]
Workmanship rule (copy exactly): [for example: a return visit within [period] is free if the fault is in our work; anything else is quoted first]
Never: diagnose a cause I have not confirmed; say that work meets a regulation; promise arrival times, outcomes or "no hidden costs"; offer discounts; criticise other firms; use customers' names (write [first name]).
Numbers: copy exactly. Show any sum line by line.
Sign-off: [your name], [firm name], [phone number].The block works by exclusion. "Never diagnose a cause I have not confirmed" stops a voicemail summary from announcing a worn washer. "Never promise no hidden costs" removes the sentence customers quote back later. And "copy exactly" on the emergency and stop-the-water lines means the safety wording a customer reads is the wording you chose, not a plausible paraphrase.
Every sample draft below is illustrative: it shows the kind of reply a prompt like this produces, with the slips worth looking for. The pass mark under each prompt is the test that counts, run on your own jobs, and the last section explains how to score it before any prompt reaches a customer.
1. A text for the call you missed
A missed call from a new number can easily turn into a customer ringing the next plumber on the list. A text within a few minutes keeps you in the race, and it can ask the questions that decide whether this is an emergency, a quote or a booking.
Write a text message to a customer whose call I missed.
What I know: [anything from the call log or voicemail, or "caller left no message"]
My availability: I can ring back at [time], or they can reply here.
Include: a one-line apology; the questions I need answered (what is happening, whether water is escaping right now, whether they can send a photo); then my emergency wording, copied exactly.
Rules: under 60 words (not counting my emergency wording), no more than three questions, no prices, no promises about arrival time.Filled in for a missed call at 7:42 pm with no voicemail and a plan to ring back at 8:30 the next morning, the draft comes back short.
Hi, sorry I missed your call at 7:42 pm. Is water escaping right now, and can you send a photo of the problem? I'll ring you at 8:30 tomorrow morning, or reply here and I'll see it sooner. [your emergency wording, copied exactly] [your name], [firm name]
Pass mark. Under 60 words before your emergency wording, three questions at most, no price, no arrival promise, and the emergency wording appearing exactly as you wrote it. If it fails any of those, fix the prompt rather than the draft.
The usual slips are an exclamation mark and "We'll be there ASAP", which the rules above should already forbid. A subtler one is typographic apostrophes. If your texting tool bills by segment, a message over 160 characters is split, and one emoji or curly apostrophe switches the whole text to an encoding that fits only 70 characters in a segment, as Twilio's documentation explains. Paste the draft into a plain-text field and retype any curly marks before you send.
2. A voicemail turned into a call-back plan
When five voicemails stack up after a morning on site, the order you ring back in matters. This prompt turns each transcript into a three-line summary, the questions to ask first, and a fallback text. It works from the transcript only, with the caller's name, number and address removed.
Below is a voicemail transcript with the caller's name, number and address removed.
Give me:
1. A three-line summary: the problem, how urgent it sounds and why, and what I still need to know.
2. The three questions I should ask first when I ring back, in order.
3. A text I can send if they do not pick up, under 50 words.
My urgent list: [for example: water escaping that they cannot stop, no water at all, a gas smell, water near electrics].
Rules: use only what the transcript says. If a word is unclear, write "unclear" instead of guessing. Mark it URGENT only if it matches my urgent list. Do not suggest a cause.
Transcript: [paste]Here is a messy transcript and the kind of plan that comes back.
Before: "hi it's about the, um, the bathroom, there's a drip from under the basin, started yesterday and it's getting a bit worse, we've put a bowl under it, can someone come this week, please call back after five"
After: Problem: slow drip under the bathroom basin since yesterday, worsening, contained with a bowl. Urgency: not on the urgent list; no mention of gas or electrics. Still needed: whether the drip stops when the small valve under the basin is closed; where exactly the water appears. Questions: 1. Can you close the small valve under the basin, and does the drip stop? 2. Is the water coming from the tap, the pipe joints or the waste? 3. Does it get worse when the tap runs? Fallback text: "Hi, it's [your name] from [firm name]. Sorry I missed you. Does the drip stop if you close the small valve under the basin? Reply here and I'll ring after 5 pm tomorrow."
Pass mark. Nothing in the summary that is not in the transcript, an urgency flag that matches your list, and a first question that most changes what you would do next (here, whether the water can be stopped).
Where it goes wrong: models like to explain. A summary that says "probably a worn washer" has turned a caller's words into a diagnosis, so the prompt forbids it and you should still scan for it. Transcription errors are the other trap, especially numbers and place names, so listen to the original before you quote a time or an address back to anyone.
3. Offering a return visit when your repair has failed
This is the call-back in the trade sense: a customer texts "it's leaking again" a few days after you replaced a tap. The temptation is to reply with an apology, an explanation or a promise. The prompt produces a calm offer to return, tied to your written workmanship rule. If you want to learn from return visits as well as answer them, the tutorial on logging the cause of every call-back, written for heating and cooling firms, shows how to spot the pattern.
Write a message to a customer whose repair we did has failed.
Original job: [one line] on [date]. What they say is wrong now: [their words, no names].
Slots I can offer: [two or three].
Say: I am sorry the problem is back, without admitting fault before I have checked; what to do meanwhile (use my stop-the-water wording exactly); what I will check; and how cost works, using only my workmanship rule.
Under 120 words. No excuses, and no blame on the customer or on the parts supplier.For a kitchen tap replaced the previous Tuesday, with the customer reporting a drip under the sink, the draft reads like this.
Hi [first name], I'm sorry the leak under the sink is back. I would like to look at it properly rather than guess from here, so I can come on Thursday morning or Friday afternoon, whichever suits you. Until then, [your stop-the-water wording, copied exactly]. When I have found the cause I will tell you before I do anything. If it is a fault in our work there is no charge for putting it right; if it is a different part, I will quote it first.
Pass mark. It apologises for the problem rather than for fault, offers two slots, includes your stop-the-water wording word for word, and promises nothing beyond your rule. Where it goes wrong is the unconditional "no charge", or a line such as "we apologise for our error" before anyone has looked. Both are decisions for you after inspection, so the check is a search for "no charge", "error", "mistake" and "our fault".
4. A fixed price for a small repair, with exclusions
Small jobs are won on speed and clarity. This prompt turns your costing into a message a customer can accept with one reply, and it forces an "included" and "not included" list so a seized fitting does not turn into an argument. For the wider question of what AI does well with plumbing quotes, the tutorial on whether a plumber can use AI to write quotes goes further.
Write a fixed-price quote message for a small plumbing job.
Job: [one line]. What I saw or was told: [notes]. Work included: [list]. Parts I will supply and my price for each: [list]. Labour: [hours] at [rate]. Total I have worked out: [figure].
Include: the total first, then the lines beneath it; two short lists, "Included" and "Not included"; how long the visit should take; how to accept (reply YES and a time); how long the price holds.
Rules: copy figures exactly; no brand names unless I give them; no guarantee except my workmanship rule; if my notes say the cause is unconfirmed, do not say the work will fix it.The main example is a leaking kitchen mixer tap that the customer has supplied a replacement for, with the two isolating valves beneath the sink stiff and worth replacing. Labour is 2 hours at $85.00, which is $170.00. Parts at your price to the customer are two isolating valves at $18.00 ($36.00), two flexible connectors at $9.00 ($18.00) and $6.00 of sundries, so $60.00. The total is $230.00.
Hi [first name], the price to fit your new kitchen tap and replace the two isolating valves is $230.00 in total: $170.00 labour (2 hours) and $60.00 parts. Included: removing the old tap, fitting the tap you have supplied, two new isolating valves and two flexible connectors, and testing for leaks. Not included: any repair to the worktop or the sealant around the tap, and any pipework found to be corroded, which I would quote before going further. The visit should take about two hours. This price holds for 14 days. Reply YES with a day that suits you to book.
Pass mark. The $230.00 equals the lines you gave (check it yourself: 170 plus 60), the exclusions are ones you would hold to, and there is no claim about cause. The slip to catch here is "all work guaranteed for 12 months" appearing from nowhere. If your workmanship rule says something different, that sentence is a promise you never made.
5. Three options for a water heater replacement
For a larger job, a choice of options turns "yes or no" into "which one". You decide the three scopes and prices; the prompt writes them clearly and refuses to invent benefits.
| Option | What it covers | Price | Leaves out |
|---|---|---|---|
| A | Replace the water heater with the same type, fittings included | $1,420.00 | Any change to the pipework layout |
| B | A higher-efficiency model, new valves and fittings | $1,780.00 | Any change to the pipework layout |
| C | Option B plus a three-year annual service plan | $2,140.00 | Parts outside the plan |
Write a water heater replacement message from the table of options I paste below. Prices: copy them to the cent.
Describe each option in two sentences: what the customer has on the day the work is finished, and what stays exactly as it is now (pipework layout, controls, anything outside a service plan).
Customer priorities from my notes: [for example: plans to stay ten years; wants lower running costs]. Point to one option only if one of those priorities leads straight to it; otherwise set the three out evenly.
Rules: no savings figures, no efficiency percentages, no energy-bill claims, no brand names unless I give them. Finish with: "Reply A, B or C and I will send dates."
Options table: [paste]The draft describes each option in two sentences and says that, because the customer plans to stay ten years and wants lower running costs, option B is worth a look; it does not say how much it would save, because your notes held no figure. That restraint is the point of the rules line.
Pass mark. The prices match your table exactly, every option says what it leaves out, and the recommendation traces to a priority the customer actually stated. Where it goes wrong: "saves up to 30% on bills" arrives uninvited. A saving is a statistic you have no source for, so delete it. Also check that option C's extra $360.00 over B is really what the service plan costs you to deliver, because a plan priced from ChatGPT's sense of "reasonable" is a plan you may lose money on.
6. An emergency call-out price before you set off
After-hours callers want the price before they commit, and a vague price is an easy way for an out-of-hours job to turn into a complaint. Build the fee from your costs first (how to build a service call fee from your costs shows how), then let ChatGPT write the message.
Write a text for a customer with an emergency, giving my price before I set off.
Arrival window: [time to time]. Out-of-hours call-out: [figure], which includes [what it includes]. After that: [rate] in [increment] steps. Parts: extra, quoted before fitting. Payment: [how and when].
Start with my emergency wording and stop-the-water wording, copied exactly. Then the arrival window, then the charges in the order the customer will meet them, then how to accept (reply YES).
Rules: under 90 words; no "no hidden costs", no guaranteed fix, no promise to be quicker than the window I gave.With a $150.00 call-out that includes the first hour, then $95.00 an hour in 15-minute steps, parts extra, and payment by card when finished, the draft reads as follows.
[your emergency wording and stop-the-water wording, copied exactly] I can be with you between 9:30 and 10:15 pm. Our out-of-hours call-out is $150.00, which includes the first hour on site. After that it is $95.00 an hour in 15-minute steps. Parts are extra and I will quote them before I fit anything. Payment by card when I have finished. Reply YES if that suits you.
Pass mark. The safety wording comes first and matches your profile character for character, every charge appears in the order the customer will meet it, and acceptance is a single reply. The slip is "no hidden charges", which sounds reassuring and is a promise that a parts surprise will test. A customer in a flooded kitchen at night is not comparing wording, but they will remember it in the morning.
7. Replying to "the other plumber was cheaper"
Price objections arrive by text and email, usually politely. The wrong replies are a discount you did not need to give or a dig at the rival. This prompt keeps your price, shows what it includes and invites a like-for-like comparison.
A customer says another plumber quoted less. Write a reply that keeps the relationship and does not lower my price.
My quote: [one-line scope, total]. What the customer says the other quote was: [figure, if given]. What I know about what it includes: [nothing, or what they said].
What my price includes that people often miss: [your list].
Rules: do not criticise the other plumber; do not say their quote is wrong or incomplete; no discount unless I state one; invite them to send me the other quote's line items so we can compare like with like. Under 120 words.Suppose the other quote was $1,350.00 against your $1,420.00 for the same-type replacement in prompt 5, and your list is removal and disposal of the old unit, new flexible connectors and valves, a pressure and leak test, and a return visit inside your workmanship period. The draft thanks the customer for telling you, says prices vary, offers to go through both quotes line by line, lists those four inclusions, and leaves the decision with them. A $70.00 gap is small enough that it may simply reflect an item the other quote left out. On its own it is not a reason to cut your price.
Pass mark. No discount, no criticism, one clear invitation. The slip is fear: "cheap quotes often hide extra costs". That is a claim about a rival you cannot support, and it reads as defensive. Cut it and keep the comparison offer.
8. A first reply to an angry written complaint
An angry complaint needs three things in the first reply: proof the customer was heard, a plain account of what you know, and a date for what happens next. It does not need an admission or a defence. Keep a record of each complaint as it comes in; the tutorial on logging, routing and replying to complaints shows how to keep that record.
A customer has sent the complaint below (names and address removed). Write my first reply.
Complaint: [paste]
What my job notes say happened: [facts only, with dates]
My next step: [for example: a return visit on [slots], or a call on [day]]. I will reply in full by [date].
Rules: open by showing I understood their main concern in their own words; apologise for the problem and for the inconvenience, without saying we were at fault; set out only facts from my notes; no blame on the customer; no legal language; one next step and one date. Under 180 words.If the complaint reads "this is the second time it has leaked and nobody has rung me back", the reply opens by saying you understand the leak has returned and that nobody got back to them, apologises for both, states that your notes show the tap fitted on Tuesday, offers Thursday morning or Friday afternoon, and promises a full answer by Friday. It does not say "we are sorry for our mistake".
Pass mark. It quotes the customer's own key phrase, states no fact that is not in your notes, accepts no blame yet, and ends with one step and one date. Where it goes wrong is over-apology. "We deeply regret this terrible experience" reads as insincere and may say more than you intend. A reply that sounds like a person is better than one that sounds like a policy.
9. A public reply to a one-star review
A public reply is written for the next customer who reads it, not for the reviewer. Calm and short beats thorough. Google's review policy bars offering anything in exchange for a customer changing or removing a review, so the reply must not do that.
Write a public reply to this one-star review. Reviewer's name and job details removed.
Review: [paste]
What I can say publicly: [for example: we attended on [date]; we want to put it right]. Do not state anything else about the job.
Rules: under 80 words; thank them; apologise for their experience without accepting blame; invite them to contact us on [phone or email] so I can look into it; no details of the work or the price; no argument; no offer in return for changing or removing the review; no mention of how many five-star reviews we have.A typical result: "Thank you for the feedback, and I am sorry the repair has not gone as you expected. I would like to look into this properly, so please contact us on [phone] and I will arrange a visit." It is thirty-seven words and says nothing the next customer can use against you.
Pass mark. Under 80 words, no job details, no defence, no incentive. The slips come in pairs: ChatGPT defends ("as you can see from our reviews") or over-shares ("we replaced the cartridge and tested it twice"). Delete both. Never post the reply before you have also sent the customer a private message, because a public "please contact us" with no follow-up is worse than silence.
10. A decision letter when you refuse a refund
Some complaints end with a no. The letter has to be firm without being cold, and it has to rest on facts, not on a legal argument you are not qualified to make. Take advice before sending anything if the customer has mentioned a solicitor or an insurer.
Write a decision letter to a customer who has asked for a full refund.
What I checked: [your inspection findings, in your words, with dates].
My decision: [for example: no refund; re-attend free of charge to adjust the fitting].
The basis: [the clause of my terms or my workmanship rule, quoted exactly].
If they disagree: [my complaints steps, for example: reply to this letter within 14 days and I will review again with a second plumber].
Rules: put the decision and the reason in the first two paragraphs; every statement of fact must come from my notes; no threats; no references to laws or regulations; polite and plain; under 220 words.Say the job was a tap fitting, your inspection found the connector slightly under-tightened, and your decision is to re-attend and adjust it at no charge but not to refund the original $230.00. The letter opens with the decision, gives the reason from your notes, offers a date for the free visit and explains how to ask for a second review.
Pass mark. Every factual sentence traces to your inspection notes, the decision comes before the explanation, and a route for disagreement is stated. The slip is the confident legal line: "under consumer law you are not entitled to a refund". You are not qualified to say it, rights vary from place to place, and a wrong statement can harm you more than the complaint did. Delete it, and if the customer's rights are unclear, ask an adviser before the letter goes out.
Reading every draft three times, as three people
The same short review step suits every prompt above, and it takes about three minutes. Read the draft three times, each as a different person.
- As the customer. Is it clear what happens next, and when? If a worried person reads only the first line, does it tell them what to do?
- As someone who later disagrees with you. That could be the customer, an insurer or an adviser. Would every sentence stand if it were read back to you? Search for "guarantee", "free", "definitely", "no hidden" and "our fault", and keep each one only if it is a promise you meant to make.
- As yourself on a tired Friday. Does it commit you to a slot, a price or a repair your diary and your costing cannot deliver?
Then run the mechanical checks: figures against your costing sheet, no leftover [first name], safety wording unchanged from your house rules, and nothing identifying left in the draft. Send it yourself, from your own phone or inbox.
Testing each prompt on last month's jobs
Do not trust a prompt because it reads well. Take last month's jobs and run each prompt on three real cases of its kind: three missed calls, three voicemails, three small quotes, three complaints, and so on. Score each draft against the pass mark in its section: 1 if it passes with less than a minute of editing, 0 if not. Keep any prompt that scores 2 out of 3, and rewrite the ones that do not, usually by adding a rule that blocks the slip you saw.
Then do the sum that decides whether it is worth the effort. If you write about 20 customer messages a week and a checked draft saves 6 minutes on each, that is two hours a week. At the value you put on your own time, say $85.00 an hour, it is $170.00 a week against ChatGPT Plus at $20 a month list price. If the maths does not hold, the problem is usually the notes you feed in: the more complete your job notes, the less the draft invents.
If you want the same messages sent automatically by your booking software rather than drafted one by one, the tutorial on AI receptionist costs and burst-pipe rules shows where automation should hand back to a person.
Questions plumbers ask about using ChatGPT for customer messages
Can ChatGPT diagnose a leak from a customer's description?
It can list possible causes, but it cannot see the pipework, and a confident wrong guess in writing becomes something the customer holds you to. Keep diagnosis out of every message until you have inspected. The prompts here tell ChatGPT to use only your confirmed findings and to say unclear when it does not know.
Is it all right to reply to a bad review with ChatGPT?
Yes, as a first draft, if you strip out names and job details and keep the reply short and calm. Do not offer anything in exchange for a customer changing or removing a review, because Google's review policy bars incentives for that. Read the reply aloud before posting; a public reply is read by future customers, not only the reviewer.
Should I tell customers a message was drafted with AI?
A message you have read, checked and sent in your own name is your own message, and routine business messages are not usually labelled. A chatbot that answers customers directly is different: tell people they are talking to a bot, and ask an adviser which disclosure rules apply to your customers.
How do I stop ChatGPT inventing guarantees or prices?
Put your workmanship wording and rule on numbers in the Project instructions, and end every prompt with the rule that figures are copied exactly and guarantees come only from you. Then search each draft for words such as guarantee, free, always and definitely before you send it.
Further reads
- AI Chatbot for Plumbers: Answer Questions, Collect Photos, Refuse Jobs — Let a website chatbot collect photos and hand over to you.
- AI Answering Service for Plumbers: Rosie, Goodcall, Smith.ai or Jobber? — Compare AI answering services when calls get missed.
- AI Quote Generators for UK Tradesmen: Built-In or ChatGPT? — What the AI in four job-software tools really does with a quote, what a general assistant adds, and a scored three-job test to settle it.
- MyBuilder vs Checkatrade for Plumbers: Cost per Job, With AI Replies — How MyBuilder and Checkatrade bill, one month costed per job won on both, and a six-week test of whether faster AI-drafted replies pay.
- AI Marketing for Plumbers: A Worked 12-Month Posts and Offers Calendar — A worked 12-month calendar for a five-van plumbing firm: frozen pipes, boiler checks, heater age and drain season, with AI drafts and a review step.
- Backflow Testing Software for Plumbers: Reminders and Reports With AI — A small plumbing firm's route to annual backflow test reminders and customer notes: register fields, reminder ladder, cover-note prompts and filing checks.
- AI Tools and AI Development: The Complete 2026 Guide — the AI hub, including every tutorial in the AI-for-business series.
Sources: OpenAI's ChatGPT pricing page and its help-centre articles on data controls and chat deletion; Twilio's documentation on SMS character limits and segments; Google's Maps policy on prohibited and restricted content (incentivised reviews).