Proof of mailing

Sometimes you may be required to provide proof that you’ve sent us mail, to verify it’s been submitted on time.

The postmark date is the filing date of the tax return, document, or payment. Generally, proof of mailing includes:

  • Postmark
  • Certified or registered mail receipt
  • Tracking information

These do not serve as proof of mailing:

  • Your unsupported statement or testimony
  • Entries you may have made in a journal or diary about timely mailing
  • Your tax preparer’s statement that their billing statements show activity close to the filing date

We’ll review the information and documents you provide. If we need more detailed information, we'll contact you.

Common scenarios

  • Penalties: If you provide proof of timely mailing, we may waive penalties or fees.
  • Amended tax return or claim for refund: If you have proof of a timely claim for refund, we may allow the refund or credit the claim to proceed.
  • Disagree with a proof of mailing decision: If you disagree with a letter we've sent you, a decision concerning a penalty, or denial of your claim for refund, follow the process to disagree or resolve an issue.