Your username is the beginning part of the main email address that you created to sign up for your ProtonMail account (email@example.com). Unfortunately, we cannot change the main login username on your account.
When you created your account, you also created a key that was matched to your username. This key allows you to send and receive emails using ProtonMail’s encryption. Changing your username would change the key that was used to send and receive all the emails in your inbox.
There are two exceptions to this rule:
1. We can remove the characters “. “_” and “-” from your username
This is possible because these characters are treated as transparent by our service. That is, username is the same as user_name and user.name, etc. Once a user takes a specific username, none of these variations can be used for a different account.
2. We can change capital letters to sentence case and vice versa
Usernames and email addresses are not case-sensitive, so these changes are purely cosmetic.
If you would like us make these changes, please contact our support team. Otherwise, you can also create a new account at protonmail.com/signup or add additional usernames to your account. For more information, see Aliases and Addresses in ProtonMail.
If you would like to merge one account into another account, please see Combining accounts.