Invoice Email Template: What to Say When You Send a Bill

Step-by-step: write and send the invoice email

1. Finish the invoice before you open a draft

   Open the invoice and verify the basics: invoice number, issue date, actual due date, total due, terms, and payment method. If the invoice only says “Net 15” or “Net 30,” also write the calendar due date in the email so the client does not have to calculate it. ^[6]

2. Use the billing contact, not just the person you worked with

   Check the contract, purchase order, client portal, or last paid invoice and copy the billing email exactly. If the client uses a separate accounts payable mailbox, put that in To and add your day-to-day contact only if they need visibility.

3. Rename the attachment before you compose

   Rename the file before attaching it. Use Invoice-[Invoice Number]-[Business Name].pdf or Invoice-[Client Name]-[Invoice Number].pdf , then open it once from your desktop to confirm it is the right version and it loads cleanly. ^{[10] [11]}

4. Write a subject line that makes sense at a glance

   Use a subject line the client can recognize in one glance. Put the word “Invoice” first, then the invoice number, then your business or project, and then the due date if it fits. ^{[10] [11]}

   Invoice [Invoice Number] from [Business Name] — Due [Month Day, Year]Invoice [Invoice Number] for [Project or Service] — Due [Month Day, Year][Business Name] invoice [Invoice Number] for [Billing Period]

5. Use the default template and keep it short

   Use the default template above or paste your own short version. The body should say what is attached, what it covers, what is due, and how to pay. The line-item detail can stay in the invoice itself. ^{[10] [11]}

6. Replace every bracketed field and keep the summary visible

   Replace every bracketed field once, then scan the draft for any brackets you missed. Keep the amount due, due date, terms, and payment methods on separate lines so the client can skim them without opening the PDF first. ^{[10] [11]}

7. Add the payment line people actually need

   Write the payment line in plain English. If you accept more than one method, list them once. If the client must include a PO number, vendor ID, or invoice number in the payment reference, say that in one short sentence. If you use a secure payment page, link to it directly. ^{[10] [11]}

8. Attach the PDF and test the exact file from the draft

   Attach the invoice as a PDF file , then open the exact attachment from the draft window before sending. If the wrong file opens or the PDF looks broken, remove it, fix it, and attach it again. Avoid image files or editable invoice attachments when a clean PDF will do. ^[11]

9. Save the wording for reuse in Mailbird

   If you want an email template for invoice sends that you can reuse, save the finished draft in Mailbird so you do not rewrite this every time. Click the Email Templates icon, choose Save draft as template , then Save as new template , and give it a name you will recognize later. Mailbird does not save To , Cc , or Bcc with the template, but it does keep a signature that is already in the draft. ^[3]

   If you are not using saved templates, keep the final wording in a plain-text note so you can paste it into any inbox.

10. Send now or schedule it, then do one final check

    If you want the invoice to arrive during working hours, schedule it with Send Later in Mailbird Next and keep the app online and connected until the send time. Right before you send, read the message once like a busy client: can they tell what the bill is for, what is due, when it is due, and how to pay in a few seconds? ^{[1] [2]}