How to Enable MFA for End Users
Multi-Factor Authentication (MFA) helps secure admin and user accounts while also preventing unauthorized access in Office 365. We recommend enabling MFA for all admins and users. Microsoft recently announced they will be requiring MFA for Partner accounts as of 8/1/2019. This article will walk through enabling MFA for end users in O365. Note: you'll need a Global Admin account to complete these steps.
1. Navigate to https://portal.office.com then Sign In with your Global Admin credentials.
2. Click the Admin icon.
3. In the O365 Admin Center click on Users > Active Users > click the More drop-down > click Multifactor Authentication Setup.
4. In the Multi-Factor Authentication window click the check-box for the users that need to have MFA enabled then click Enable. In the "About enabling multi-factor auth" window click Enable multi-factor auth.
Note: Only 20 users can be displayed per page so if you have more than 20 users you'll need to repeat step 4 and 5 for each page.
5. Click Close in the "Updates Successful" window.
6. At this point MFA has been Enabled for your users but you may want to consider Enforcing MFA for your users as well. When MFA is Enabled users will be prompted to setup MFA the next time they sign into https://portal.office.com but any current connections are not disrupted. When MFA is Enforced users will be prompted to setup MFA the next time they sign into https://portal.office.com and any current connections are closed.
If you want to Enforce MFA as well simply click the check-box for users that have MFA enabled then click Enforce. In the "About non-browser applications" window click Enforce Multi-Factor Auth.
7. Administrators may also want to customize the MFA settings that are available to users. To access the MFA settings click the Service Settings tab. On this page Administrators can choose if app passwords are allowed, which verification methods users can use, and if MFA can be remembered on trusted devices for 1 - 60 days. If any settings changes are made remember to click Save at the bottom of the page.