In addition to this, we offer an Encrypt Message for Non-ProtonMail users feature that allows you to send E2EE messages to any email user without the need for PGP. The recipient receives an email telling them that they have been sent a secure encrypted message. To read the message, they must enter a previously agreed-upon password. They can then respond to your message so that their response is also E2EE.
How to Encrypt Message for Non-ProtonMail users
1. Compose your message as usual. Any attachments will also be end-to-end encrypted. Before clicking Send, however, click the Encryption button (with the padlock icon).
By default, messages sent using the Encrypt Message for Non-ProtonMail users feature will expire 28 days after they are sent. You can change this using the expiration timer.
2. Choose and confirm a message password. If you wish, you can also add a password hint to jog your recipient’s memory. Click Set when you are done (or tap Apply if using our Android or iOS apps).
3. Back in the main composer screen, click Send.
How to read and respond to an encrypted email
The recipient of a message sent using our Encrypt Message for Non-ProtonMail users feature will receive a regular email explaining that a secure message has been sent to them. To view the message, they must:
1. Click the View Secure Message button.
2. Enter the password that you discussed and agreed upon previously. The password hint option can be very helpful here.
3. The message will be decrypted locally in their browser for them to read. No one else can read the message.
4. They can then Reply Securely to the message. This reply is end-to-end encrypted. Full text formatting options are available for this, and any attachments they send will also be end-to-end encrypted.
Because this is a free service, and in order to combat abuse by spammers, you can only reply to each message a total of five times.
You can always create a free secure email account to enjoy the benefits of encrypted communication without reply limits and without the need for a message password. Messages between ProtonMail users are automatically encrypted without the need for a message password.
Is this safe?
ProtonMail uses open-source encryption algorithms to secure email communications with end-to-end encryption. This means the messages cannot be intercepted in transit, nor can they be accessed by either ProtonMail or any other email provider. The only people who can read the messages are the sender and recipient.
ProtonMail’s secure messages are safe to open, and it is safe to click on View Secure Message. You can verify the security of the secure message by making sure you’re connected to the official ProtonMail website (and not a phishing site). The domain name should be protonmail.com.
If you want to be extra secure, you can also verify our SSL certificate. Furthermore, you can also check the secure message’s header information to make sure our DKIM and SPF records match what they should be. If you have any doubts, you can contact our security team at email@example.com.
Encryption made easy
If you also want to send secure messages, you can get a free ProtonMail account. ProtonMail accounts also benefit from automatic end-to-end encryption between ProtonMail accounts, so if you have sensitive communication needs and both parties are using ProtonMail, you can ensure that your communications cannot be intercepted or handed over to third parties.