In a blog post, Twitter cited abuse of the phone-number based 2FA by bad actors as the reason for the change. Users who fail to switch to another 2FA method or become Twitter Blue subscribers will lose SMS-based 2FA security after March 20. However, alternative two-factor verification options such as authenticator apps and security keys will remain available. Twitter CEO Elon Musk has previously claimed that the company is being scammed by phone companies for $60m/year of fake 2FA SMS messages.
The Twitter Blue service, which includes the option to purchase a verification badge, costs $8 per month. Users have 30 days to disable text authentication and switch to the other two options provided before the feature is automatically disabled on March 20. Many users have expressed their anger at the change.
Celebrities such as Alyssa Milano and Lauren Jauregui have expressed concern over the risk posed to their accounts as public figures. This decision is one of several controversial moves made by Twitter's CEO Elon Musk, who faced backlash over Twitter Blue's sale of verification badges and mass layoffs.
While other authentication methods such as Duo and Google Authenticator are still available, some users may consider leaving the app as a result of this decision.