Proton Mail now supports post-quantum encryption for all users, including free accounts

Proton Mail has enabled optional post-quantum protection on all its plans, including free accounts. Once activated, users can generate new post-quantum-ready encryption keys to secure emails against both present-day threats and potential future attacks by quantum computers. This update responds to concerns that large-scale quantum computing could eventually undermine traditional cryptographic methods such as RSA and elliptic curve cryptography.

Building on this advancement, Proton Mail is introducing support for OpenPGP version 6. The updated framework allows the use of modern encryption algorithms, including those designed for resistance against quantum-based decryption techniques. These upgrades facilitate secure communication for both personal and business users.

While transitioning to these quantum-safe keys, users can continue familiar key management practices, such as generating new keys, and marking keys as obsolete or compromised, just as with legacy RSA or elliptic curve cryptography keys. However, activating post-quantum protection only impacts new encrypted messages going forward; existing emails in the mailbox are not re-encrypted at this time.

Proton is also collaborating with other email providers and clients, such as Thunderbird, to promote cross-provider standards for quantum-safe encrypted email. This step aims to help users maintain secure communication, regardless of their chosen email service.