Debt validation letter: make a collector prove the debt
When a debt collector contacts you, you can ask them to prove the debt. Timing matters.
The validation notice
Collectors must send you a validation notice with the amount, the creditor and the last day you can dispute (the end of the validation period, about 30 days after you receive it).
Dispute in writing within the window
If you dispute in writing by that date, the collector must stop collecting until it mails you verification of the debt. Send it certified mail and keep a copy.
What to ask for
- The original creditor's name and address
- How the amount was calculated, including interest and fees
- Proof they own the debt or may collect it
Our free letter builder writes this letter for you.
Things to know
Asking for validation is not admitting you owe it. If the collector reports the debt while you dispute it, it should be marked as disputed. If you've been served with a lawsuit, don't ignore it: get help from a lawyer or LawHelpCA.org.
Questions
What if I missed the 30-day window?
You can still dispute and ask for proof, but the collector doesn't have to pause collecting. You can still dispute the item with the credit bureaus.
General information, not legal advice. Sources: CFPB, FTC. Checked November 2026.