Two Factor Authentication (also known as 2FA), allows you to add another layer of verification to the login process, requiring a second piece of information in addition to your email address and password in order to log in to Trello. The purpose of 2FA is to make it more difficult for an attacker to gain control of your account by requiring a code that is only accessible via a second authentication device. Trello currently supports text message (SMS), an Authenticator app, and backup codes as Two Factor Authentication codes.
You can visit https://trello.com/2fa to enable Two Factor Authentication for your account. You’ll need to log into your Trello account with email and password to see that page.
After clicking the big green button to add Two Factor Authentication, we strongly recommend that you print out backup codes, in case you lose access to your authentication device.
You can use the Text Message configuration to enable Two Factor Authentication (SMS), or you can use an Authenticator App instead by clicking on the link below the “Send Verification Code” button.