Send a demand letter for an unpaid invoice
When emails go unanswered, a formal demand letter sent with proof of delivery often gets an invoice paid, and it's the record you'll want if the dispute goes further.
How it works
01Pull the details
Invoice number, amount, the work delivered, the original due date and any reminders you've sent.
02Set a clear deadline
State the amount owed, how to pay, and the date by which you expect payment.
03Send it certified
Certified Mail ($14.99) gives you tracking and proof of delivery; add a return receipt ($19.99) for a signature.
What to include
- Your business name and contact details
- Invoice number, date, amount and what it was for
- Payment instructions
- A specific deadline
- What you'll do next if it isn't paid, stated factually
Ask your agent
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Common questions
Is a demand letter legally required?
Not always, but it's a common step before small-claims court or collections, and proof that you sent it can help. Check the rules where you are.
Should I attach the invoice?
It helps. Combine your letter and a copy of the invoice into one PDF and upload it.
Do you give legal advice?
No. We print and mail what you or your agent writes.
Sendpaper prints and mails what you or your agent writes. We're not a law firm or tax preparer and don't give legal or tax advice; for deadlines and the right address, check the notice itself, the agency, or a professional.