Quick answer
Send invoices as a PDF attachment to the client’s accounts payable email, with the person who hired you on CC. The subject line should include your business name, invoice number, amount and due date so AP teams can triage without opening it. Yes, emailed PDFs are fully ATO-compliant in Australia — you don’t need to print or post anything.
Step 1 — Find the right recipient
The fastest path to payment is the right inbox. Order of preference:
- Accounts payable email — usually accounts@, ap@, or invoices@ at the client’s domain
- The person who hired you — on CC so they can internally approve
- The PO contact if your invoice has a purchase order number
For small businesses with no AP team, send to the owner directly. For larger clients, always email-pollute both AP and your contact — the contact won’t pay you, AP won’t approve you.
Step 2 — Get the subject line right
A good subject line is searchable and scannable. The format:
{Your business} — Invoice #{number} — {amount} due {date}Real examples:
- Smith Plumbing — Invoice #INV-2026-0034 — $1,210 due 30 Jun
- Jane Doe Design — Invoice #INV-2026-118 — $660 due on receipt
- Acme Consulting — Invoice #2026-Q2-44 — $4,400 due 7 Jul (Net 14)
Why this works: AP teams can find your invoice 6 months later via search, the dollar figure tells them how urgent it is, and the due date pre-empts the “when’s this due?” reply.
Step 3 — Attach the PDF (don’t paste it in the body)
The PDF is the legal record. Most accounting systems (Xero, MYOB, SAP, etc.) auto-import PDF attachments — pasted invoice text doesn’t flow through.
Name the file properly: INV-2026-0034_SmithPlumbing.pdf, not Invoice.pdf. Generic filenames disappear in the AP team’s download folder.
Step 4 — Write a short, useful body
Copy-paste template (standard send)
Hi {first name},
Please find attached invoice #{number} for {brief work description}.
Amount due: {amount} (incl. GST)
Due date: {date}
Reference: please use "{invoice number}" on your transfer
Bank: {bank name}
BSB: {BSB}
Account: {account number}
Account name: {account name}
Let me know if you need a different format or anything for AP. Thanks!
{Your name}
{Your business} — ABN {ABN}Copy-paste template (deposit invoice)
Hi {first name},
Attached is the {%} deposit invoice for {project}, which I'll start once it's settled. The balance will be invoiced on completion.
Amount due now: {amount} (incl. GST)
Due date: {date}
Bank details on the invoice. Reach out if you need anything else.
{Your name}Copy-paste template (first follow-up)
Hi {first name},
Just following up on invoice #{number} ({amount}, due {date}). I haven't seen it come through — could you confirm it landed with AP and let me know when payment's expected?
Happy to resend if it got lost. Thanks!
{Your name}Step 5 — Track whether it landed
Email clients like Outlook offer read receipts, but they’re unreliable. Better options:
- An invoicing app that shows you when the invoice was opened
- A short polite check-in 7 days after sending if you haven’t had an ack
- Always keep your sent folder — AP queries always start with “we never got it”
Why “send from Gmail” is costing you payments
Invoices from yourname@gmail.com hit spam filters more often than invoices from you@yourbusiness.com.au. They also look less credible — AP teams flag “personal” senders for extra checks. If you’ve set up a business domain for email, use it.
For an even better deliverability story, see how to send invoices from your own email address — that’s a deeper setup using SPF/DKIM/DMARC.
Common mistakes
- Sending only to the person who hired you — they’ll forget; AP needs the original
- No bank details in the email body — force AP to open the PDF and you add days
- One huge invoice for 6 months of work — bill closer to the work; smaller invoices clear AP queues faster
- Sending Friday afternoon — goes to the bottom of Monday’s pile
- Pasting the invoice as inline text — doesn’t flow into accounting software
The faster way
Doing all of the above manually in Gmail for every invoice is exactly what invoicing apps automate. Free Invoice App:
- Generates the PDF
- Auto-fills the subject line
- Sends to the client (with CC) in one click
- Shows you when it’s opened
- Lets you send from your own domain on Pro+
Frequently asked questions
Is an emailed PDF invoice legally valid in Australia?
Yes. The ATO accepts electronic tax invoices (including PDFs) as long as they contain the required information — ABN, “Tax invoice” wording, date, description, GST, totals, and the buyer’s ID for invoices $1,000 or over. You don’t need a paper copy.
Should I attach the invoice as a PDF or paste it in the email body?
Always attach a PDF. The PDF is the legal record; the email body is the cover letter. Many accounts payable systems forward PDFs straight into the queue — a pasted invoice in the body gets ignored.
What should the invoice email subject line say?
Include your business name, the invoice number, and the amount due. Example: “Smith Plumbing — Invoice #INV-2026-0034 — $1,210 due 30 Jun”. This format is searchable, scannable, and accounts payable teams can triage it without opening the email.
Who should I CC on an invoice email?
Send the invoice directly to the accounts payable email (often accounts@ or ap@). CC the person who hired you so they know it’s been sent and can approve internally. Never send to one without the other.
Should I send invoices from my Gmail or a business email?
A business domain (you@yourbusiness.com.au) lands in inboxes more reliably and looks more professional. Free Invoice App Pro plans support sending from your own domain so invoices come from your brand, not a shared sender.