How to send an invoice by email

The email is not a covering note; it is the thing that decides whether the invoice reaches the payment run this month or next. Most of the work is making the message easy to forward, because the person who receives it is rarely the person who pays it.

Send it to a person and a queue

Put the person who hired you in the To field and the accounts payable address in copy, or the other way round if the client has told you which they prefer. Sending only to your contact makes payment depend on them remembering to forward it.

Write a subject line that survives being searched for

  • Your business name, so it is findable months later
  • The word Invoice
  • The invoice number
  • The amount and the due date, if they fit

Keep the body short and complete

Three or four lines: what the invoice is for, the amount, the due date, and how to pay. Anything longer is read as a negotiation. A payment link belongs here, and so does the PDF — the link is how a person pays, the PDF is what a finance system files.

Attach a PDF, always

A PDF renders the same everywhere, cannot be edited by accident, and is what most accounting systems expect to store. An invoice that exists only inside a portal or an HTML email is one the client's own records will not have.

Make an invoice PDF

Common questions

Should the invoice be in the email body or attached?
Both. Summarise it in the body so it can be triaged without opening anything, and attach the PDF so it can be filed.
When is the best time to send an invoice?
The day the work is delivered. Beyond that, earlier in the week and earlier in the month tends to catch a payment run that later sending misses.
Do I need read receipts?
No, and they read as distrust. A dated record of when you sent it, plus a scheduled reminder on the due date, does the same job without the tone.

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