How to Send an Invoice by Email (With Copy-and-Paste Templates)

To send an invoice, create it as a PDF, attach it to an email addressed to the person who pays, and write a subject line with the invoice number, amount and due date. Keep the email short: say what the invoice is for, how much is owed, when it is due and how to pay. Then save a copy and set a reminder for the due date.

Below are the exact steps, what to avoid, and four email templates you can copy.

How to send an invoice in 6 steps

1. Create the invoice. Use a template or our free invoice generator and check it has everything on our invoice checklist.
2. Download it as a PDF. Name the file clearly, for example INV-0042-Patel-Decorating.pdf.
3. Find the right recipient. Send it to whoever approves payment, and copy in your main contact if that is someone else.
4. Write a clear subject line. Invoice number, your business name and the due date.
5. Write a short email body. Amount, due date, payment details and a thank you.
6. Record and follow up. Log the invoice, then send a friendly reminder if it is not paid by the due date.

The best subject lines for invoice emails

Situation	Subject line
Standard invoice	Invoice INV-0042 from Patel Decorating, due 17 Nov 2026
Monthly retainer	October 2026 invoice (INV-0043), Patel Decorating
Deposit	Deposit invoice INV-0044 for kitchen project
Reminder	Reminder: invoice INV-0042 due today

Invoice email templates

1. First invoice to a new client

Hi Jane,
Thank you for choosing Patel Decorating. Please find attached invoice INV-0042 for £575.00 for painting the living room, completed on 31 October.
Payment is due by 17 November 2026 by bank transfer to sort code 00-00-00, account 12345678, using INV-0042 as the reference.
If you have any questions, just reply to this email.
Kind regards,
Sam

2. Repeat client

Hi Tom,
Attached is invoice INV-0043 for October's work, totalling £1,200.00 and due on 30 November. Payment details are on the invoice as usual.
Thanks again,
Sam

3. Deposit before work starts

Hi Priya,
As agreed, here is a deposit invoice for 30% of the kitchen project (£900.00). Once it is paid I will book in your start date. The balance will be invoiced on completion.
Best wishes,
Sam

For deposits and upfront payments, a proforma invoice is often the cleaner option.

4. Friendly reminder on the due date

Hi Jane,
Just a quick reminder that invoice INV-0042 for £575.00 is due today. I have attached it again for convenience. If you have already paid, thank you and please ignore this email.
Kind regards,
Sam

If the invoice is still unpaid after that, follow our step-by-step guide to chasing an unpaid invoice.

Common mistakes when sending invoices

• Sending an editable file. Word and Excel invoices can be changed and look different on each screen. Always send a PDF.
• Vague subject lines. "Invoice" on its own gets lost. Include the number and your business name.
• No payment details. If the client has to ask how to pay, you will be paid later.
• Waiting to invoice. Invoice the day the work finishes, while it is fresh in your client's mind.
• Duplicate or missing numbers. Each invoice needs a unique number. See how to number invoices.

Other ways to send an invoice

Post: some clients, councils and older businesses still prefer paper. Print the PDF and keep a digital copy. WhatsApp or text: useful for quick jobs, but email a copy too. Client portals: larger companies may ask you to upload invoices to a supplier portal, so ask about this before you start the work.

Ready to send your next one? Create an invoice and download the PDF in under two minutes, free and with no sign-up.

Frequently asked questions

What is the best format to send an invoice in?

PDF. It looks the same on every device, cannot be accidentally edited and is what accounts teams expect. Avoid sending Word or Excel files, which can be changed and often display differently.

What should I put in the subject line of an invoice email?

Include the word "Invoice", the invoice number, your business name and ideally the due date, for example "Invoice INV-0042 from Patel Decorating, due 17 Nov 2026".

Can I send an invoice by WhatsApp or text?

You can, and many tradespeople do for small jobs. Still email a PDF copy as well so both you and your client have a proper record for accounts and tax.

When should I send an invoice?

As soon as the work is finished or the goods are delivered, ideally the same day. For ongoing work, invoice on a fixed schedule, such as the last working day of each month.

Who should I send the invoice to?

Ask your client before the job who handles payments. In larger companies it is often an accounts payable address rather than your day-to-day contact, and some need a purchase order number on the invoice.