Q: (from Ben)
Some reports this is free others say a cost
Is this included in Office 365?
The quick answer is that the basics of Multifactor Authentication are included in Office 365 (free) but advanced features are added with Azure Active Directory Premium ($6 per user per month). From the table found at:
you can see that Administrators can protect Office 365 accounts with MFA using a phone, an app, or SMS as the 2nd authentication factor using the basic MFA included with Office 365. But if you want to customize the greeting, PIN mode, or generate fraud alerts and MFA reports, you would need the MFA that comes with Azure AD Premium. And I would be remiss if I didn’t point out that if you are looking at Azure AD Premium, you should look at the Enterprise Mobility Suite; for $8.75 per user per month you not only get Azure AD Premium, but you also get Microsoft Intune, Azure Rights Management, plus Advanced Threat Analytics.