Mobile numbers are now required to verify your account at sign in, which is not a step we have taken lightly.
TaxAct works closely with the IRS to ensure that your tax data remain secure. The IRS is migrating its former model, "Trusted Customer Requirements," to align with a new protocol called: "NIST* Authenticator Assurance Level 2"
Mobile numbers are bound to a specific device (unlike email addresses), and are therefore considered by the IRS more likely to prove authenticity of ownership of the TaxAct account. As an IRS Summit Industry Partner, TaxAct is required to move in this direction by the IRS.
(*NIST = National Institute of Standards and Technology)