GLOSSARY
Adult Signature Required
By Justin Winter · Updated August 28, 2026
A USPS extra service that requires the signature of someone 21 or older at the address before a piece is released, with no signature by anyone younger accepted.
Adult Signature Required is stricter than an ordinary signature service: USPS will not leave the piece, and will not release it to anyone the carrier cannot reasonably judge to be at least 21, without checking identification. If no qualifying adult is available, the piece goes to the post office for pickup instead of a second delivery attempt at the address.
It is built for items with a legal age restriction, not for general "make sure someone signs" needs — for a document or letter, Certified Mail with a Return Receipt records who signed without policing their age.
See also
- Signature Confirmation — A USPS extra service that requires a signature at delivery and keeps the record on file, without the mailing receipt Certified Mail gives you.
- Restricted Delivery — A USPS extra service that limits delivery to the addressee, or to someone the addressee has authorised in writing.
- Return receipt — A USPS add-on that sends the sender a copy of the recipient’s signature as proof the piece was delivered and to whom.
Back to the full mail glossary.