How plumbers should invoice: a practical guide

The moment the leak stops, if it is emergency work — gratitude has a short half-life and an invoice sent at 1am after a midnight call-out is very often paid by lunchtime. Installations invoice on commissioning, not on the last day of labour. Itemise labour and materials separately, put a real due date on it rather than "on receipt", and send it as a PDF the client can forward to whoever actually pays. For plumbers, the detail that matters most: the call-out fee and the first hour are usually one line, not two, and splitting them makes the bill look padded.

How to price the work

A call-out covering the first hour, then an hourly rate afterwards, is the standard domestic shape. Bathroom installations and boiler work price as fixed quotes. Mixing the two on one document confuses people — pick one per job.

What the lines should look like

For an emergency call-out, a line that reads well is:

Emergency call-out and first hour, out of hours

Specific enough that the person approving payment — often not the person who hired you — can see what they are paying for. Here is the same job as a finished invoice line:

Emergency call-out and first hour, out of hours
Leak isolated at mains, failed compression joint replaced — £145.00

Deposits

Emergency and repair work, nothing. Installations with a boiler or suite ordered in, typically 40–50% to cover the goods.

Materials and markup

Parts at cost plus a stated markup, or parts included in a fixed price. What causes arguments is doing it one way verbally and the other way on the invoice.

The mistake plumbers make most

The call-out fee and the first hour are usually one line, not two, and splitting them makes the bill look padded.

The out-of-hours premium. A customer who called at 11pm is not price-sensitive at 11pm and extremely price-sensitive at 9am. Quote the call-out rate on the phone before you travel, and name it on the invoice as "out of hours" so it is not mistaken for the standard rate.

Boiler and appliance registrations

Warranty registration and any statutory notification are yours to complete, and the customer usually cannot register the appliance themselves. Do it the same day and put the registration number on the invoice. It is a two-minute job that prevents a warranty claim failing in year three and being blamed on you.

Getting paid, in this trade specifically

Emergency customers pay fastest, bathroom installations slowest, because the customer is often waiting on a tiler or an electrician and treats the whole project as one bill. Invoice your part on completion of your part, and say so at quote stage.

The rest is the same for everyone: what has to be on the document, how to number it, how to chase it and how long to keep it. If you are registered for tax, the rate and the label depend on your country.

EstimateBill tracks what is unpaid, reminds you on the due date, and writes the follow-up message for you in three tones. See how the reminders work.