How to Send an Invoice (Email Templates Included)
The right file format, subject line, recipient and follow-up cadence for invoices that actually get processed.
Send a PDF, always
PDFs render identically everywhere and cannot be edited accidentally. Never send a spreadsheet or a word-processor file as your invoice of record.
Name the file properly
Invoice-2026-0041-AcmeLtd.pdf. Accounts-payable teams handle hundreds of files a week; a descriptive name gets yours filed instead of lost.
Send it to the right person
Ask for the accounts-payable address at kickoff. CC your day-to-day contact so they can approve it internally.
Email template — first send
Subject: Invoice 2026-0041 — Acme Ltd — due 14 Aug 2026
Hi Sam, please find attached invoice 2026-0041 for £2,400 covering the August retainer. Payment is due by 14 August; bank details are on the invoice. Happy to answer any questions. Thanks, Priya.
Email template — polite reminder
Subject: Reminder — invoice 2026-0041 due today
Hi Sam, a quick reminder that invoice 2026-0041 (£2,400) is due today. I have re-attached it for convenience. If it is already scheduled, ignore this. Thanks, Priya.
Escalating
After 14 days overdue, reference your late-payment terms and ask for a specific payment date rather than a vague update.
Create the PDF first with our generator.
Priya Raman
Priya Raman writes about invoicing, cash flow and small-business finance for Invoice Creator. Every guide is reviewed against the fields our own invoice generator produces, so the advice matches the tool.
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