When Salesforce enforces multi-factor authentication (MFA) at the org level, the "Require multi-factor authentication (MFA) for all direct UI logins to your Salesforce org" setting is greyed out in Salesforce Sales Cloud and Service Cloud orgs. Users cannot turn the setting off.
This article answers why the "Require multi-factor authentication (MFA) for all direct UI logins to your Salesforce org" setting is greyed out, and what MFA enforcement requires for Username/Password and SSO logins.
When MFA is enforced at the org level, Salesforce greys out the setting. The enforcement applies to both Username/Password and SSO logins.
Users who authenticate with Username/Password must use a Salesforce-supported MFA verifier.
Users who authenticate through SSO must have the Identity Provider (IdP) send a compliant AMR/ACR signal. For details, see the article Prepare for MFA Enforcement for All Employee Users.
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