My payment was mailed but the post office was unable to deliver it. What should I do

If your payment was mailed but the post office was unable to deliver it, the following steps should be taken:

1. Wait for the Payment to be Returned: The IRS will receive your payment back if the post office is unable to deliver it. Once the IRS receives the returned payment, they can reissue it if they receive an updated address in time.
2. Update Your Address: To ensure that the payment can be reissued to the correct address, you need to provide the IRS with your updated address. You can find information on how to update your address with the IRS by referring to the relevant IRS procedures.
3. Claim the Recovery Rebate Credit: If you do not receive your payment within the specified time frame, you may be eligible to claim the Recovery Rebate Credit when you file your tax return for the relevant year.

By following these steps, you can address the issue of an undelivered mailed payment and ensure that you receive your payment in a timely manner.

Sources:
§ 7502. Timely mailing treated as timely filing and paying
Publication 5420-C (10/2020)
CCA 200504028
CCA 200503031