Email is how the vast majority of freelancers and small businesses send invoices. It's fast, free, and creates a paper trail. But there's a big difference between a professional invoice email that gets paid quickly and a sloppy one that gets ignored.

Here's the exact process to use.

Should You Send a PDF or a Link?

Always send a PDF attachment, not a link to an online invoice viewer. Here's why:

  • PDFs open in every email client without any login or account
  • PDFs get saved, printed, and forwarded easily
  • Clients can download and file the PDF for their own records
  • Some corporate finance teams won't process invoices without a PDF attachment
  • Links can look like phishing attempts and get blocked by spam filters

If your invoicing software doesn't generate a PDF, that's a problem worth solving.

The Right Email Subject Line

Your subject line should make it immediately clear what the email is about and how much money is involved. A busy accounts payable person processes hundreds of emails a day — make yours easy to act on.

Good format:

Invoice #INV-0042 from [Your Business Name] — $1,840 due 23 July 2026

Include: invoice number, your business name, the amount, and the due date. All in the subject line.

Don't write:

  • "Invoice" (tells them nothing)
  • "Invoice attached" (still nothing)
  • "Hi, please see attached" (this will get lost)

The Invoice Email Body

Keep it short. The invoice itself contains all the details — the email is just a professional cover note.

Hi [First name],

Please find attached invoice #INV-0042 for [brief description of work], totalling $1,840 (incl. GST), due 23 July 2026.

Payment details are on the invoice. Please use the invoice number as your payment reference.

Let me know if you have any questions.

[Your name]
[Your phone number]

That's it. No need to restate all the line items in the email body — that's what the PDF is for.

What the PDF Invoice Must Include

The invoice PDF should clearly show:

  • Your business name and contact details
  • Invoice number and date
  • Due date (calculated from your payment terms)
  • Client name and address
  • Description of work with line items
  • Subtotal, GST amount, and total
  • Your bank account name and number
  • Payment reference (invoice number)

Missing any of these, especially the bank account number and invoice number reference, causes payment delays.

When to Send the Invoice

Send invoices immediately — don't batch them or wait until the end of the month (unless your contract specifically requires end-of-month invoicing).

The moment the work is done (or the milestone is hit), send the invoice. Two reasons:

  1. The work is fresh in the client's mind — less likely to question it
  2. Your payment terms start from the invoice date — every day you delay costs you cash flow

Following Up on Unpaid Invoices

Even with great invoices, some clients pay late. Have a consistent follow-up process:

Day of due date (or 1 day after):

Subject: Friendly reminder — Invoice #INV-0042 due today

Hi [Name], just a quick reminder that invoice #INV-0042 for $1,840 was due today. Please let me know if you have any questions or if there's anything I can help with.

Day 7 after due date:

Subject: Invoice #INV-0042 — 7 days overdue

Hi [Name], I'm following up on invoice #INV-0042 for $1,840, now 7 days overdue. I've re-attached the invoice for convenience. Please could you confirm an expected payment date?

Day 14+ after due date: Phone call. Email is now insufficient.

Using Invoicing Software to Send by Email

Good invoicing software handles the email for you — you click "Send" from inside the app and it emails the PDF directly to your client with a professional subject line and covering note. You get a copy for your records.

In MyBillDash, the send flow is: create invoice → click Send → confirm the client email → done. The PDF is generated and emailed in seconds. Try it free for 1 month.