What the ATO requires
For a tax invoice under $1,000, the ATO expects seven things. Miss one and the invoice can be sent back by the one customer whose bookkeeper is thorough.
- The words Tax Invoice
- Your business name
- Your ABN
- The date it was issued
- A description of what you supplied — the work, and the quantity or hours
- The GST amount, or a statement that the total includes GST
- Over $1,000, also the buyer's identity or ABN
Plumbers normally add a licence number too. It is not an ATO requirement, but on compliance-certificate work the customer or their insurer will ask for it eventually, and it is easier to have it on every invoice than to reissue one.
The four lines that cause plumbing invoice disputes
1 · Call-out fee — always its own line
This is the single most argued item on a plumber's invoice, and almost always because it was folded into labour. A customer who sees three hours charged for a ninety-minute job assumes they have been overcharged. The same money, itemised as Call-out / attendance, reads as normal — because it is.
Say the fee when the job is booked, not when the invoice lands. Every dispute worth having traces back to somebody hearing the number for the first time on paper.
2 · After-hours and emergency rates
Nights, weekends and public holidays cost more, and the invoice should say after-hours rate rather than showing a higher number with no explanation. A burst pipe at 11pm is exactly when a customer agrees to anything and exactly when they scrutinise the invoice afterwards.
3 · Materials, shown separately, with markup
You source it, cart it, warrant it and fit it. A markup on materials is standard trade practice, not a rort — but it has to be visible as materials, not hidden inside an hourly figure. List the unit, the tap set, the fittings.
4 · Variations, priced apart from the original job
The wall came off and the pipe behind it was worse than anyone could see. That is a variation, and it belongs on its own line with its own price. Rolling it into the original figure makes the whole quote look like it was wrong from the start, which is the fastest way to turn a good job into an argument about honesty.
A worked example
A hot water unit replacement, GST-registered, invoiced the day the job finished.
| Description | Qty | Rate | Amount |
|---|---|---|---|
| Call-out / attendance | 1 | $90.00 | $90.00 |
| Supply 250L electric storage hot water unit | 1 | $1,340.00 | $1,340.00 |
| Remove and dispose of old unit | 1 | $180.00 | $180.00 |
| Install, connect, commission and test | 3.5 hr | $135.00 | $472.50 |
| Tempering valve — replace (variation) | 1 | $210.00 | $210.00 |
| Subtotal (ex GST) | $2,292.50 | ||
| GST 10% | $229.25 | ||
| Total (inc GST) | $2,521.75 |
Five lines, and every one of them answers a question before it is asked. The tempering valve is marked as a variation because it was not in the original quote — the customer can see exactly what changed and why the number moved.
Invoice or quote — which one you need
A quote is a price before the work. An invoice is the bill after it. They carry different fields and different risks, and the numbers should match unless a variation explains the gap.
If you are pricing the job rather than billing it, use the plumber quote template instead — it builds a priced quote with a deposit and licence details.
Or skip the template entirely
A template is a good answer to this invoice. It is a poor answer to the two-hundredth — you retype the customer, work out the GST again, and later try to remember who paid.
Yamate turns a finished job into an invoice with the quoted numbers already in it, keeps the call-out fee and variations straight, and shows you what is still owed. Try it free for 30 days — everything unlocked, no card. Then from $19/mo (founder price, until 30 Sept).
Questions plumbers ask
What has to be on a plumber's invoice in Australia?
The words Tax Invoice, your business name and ABN, the date, a description of the work, and the GST amount or a statement that the total includes it. Over $1,000, the buyer's identity or ABN as well. Most plumbers add a licence number.
Is it legal to write your own invoice?
Yes. There is no requirement to use particular software or a particular form. It has to carry the fields above and it has to be accurate. A handwritten invoice is legal on the same terms — it is just slower and easier to get wrong.
Should the call-out fee be a separate line?
Yes. It is the single change that prevents most invoice arguments. Buried in labour it looks like an inflated hourly rate; on its own line, described as attendance, it reads as what it is.
Do I charge GST on a plumbing invoice?
Only if you are registered for GST. If you are, show the GST amount or state that the total includes it. If you are not registered, do not charge it.
What if the job changed once I opened it up?
Price it as a variation on its own line. The original figure stays as quoted and the variation explains the difference. That is the difference between a customer who understands the bill and one who thinks the quote was never real.
Next steps
General information for Australian tradies, not tax, legal or financial advice. Invoice requirements are set by the ATO and licensing rules are set by each state and territory — check yours before relying on this page. Yamate helps you prepare and issue invoices; it does not lodge your BAS or report anything to the ATO on your behalf.