Abstract: A system and methods that prioritize email based on the use of cryptographic signatures are described. The system can allow email to be received without blocking a subset of the email. When email is received, the system can determine whether the email is received from an approved user who has exchanged public keys with the email recipient and determines whether the email includes one or more cryptographic signatures. Emails with signatures that are successfully verified can be identified as having a higher priority level than emails without the cryptographic signatures. The emails with the higher priority level can be presented to the recipient in a priority inbox. Emails without the signatures can be placed in a different folder, which is not presented to the user by default, but can be presented to the user in response to a request from the user.