The Postal Service provides one-time use pins via SMS text messages to authenticate External Digital Signature users as part of our Two Factor Authentication (2FA). In order to participate in digitally signing a document, the external users provide their cell numbers to Postal individuals over email or phone conversations. This is purely voluntary — if the external party chooses to not participate in digitally signing a document, they can simply opt-out by declining the offer made by a Postal employee.
Digital Signature Text Messaging (Short Code 96429)
Supported Phone Numbers
The Postal Service Digital Signature supports SMS text messaging for domestic and international users.
Participating carriers include AT&T, T-Mobile®, Verizon Wireless, Sprint, Boost, U.S. Cellular®, MetroPCS, Virgin Mobile, and Cricket - PLEASE CONTACT YOUR TELECOMMUNICATIONS PROVIDER FOR FURTHER DETAILS.
Privacy Act Statement
Your cell phone number will be used for USPS Digital Signature Two-Factor Authentication. Providing the information is voluntary, but if not provided, we will be unable to offer this service to you. We do not disclose your information to third parties and your cell phone number is expressly used to facilitate Digital Signature transactions only.