What is the difference between Microsoft 365 and Office 365?
Office 365 is the productivity workload — Exchange Online, SharePoint, OneDrive, Teams, and the Office apps. Microsoft 365 is Office 365 bundled with Windows 10/11 Enterprise use rights, Entra ID (P1 in E3, P2 in E5), Microsoft Intune, and the security and compliance add-ons (Defender for Endpoint, Purview premium, PIM, Identity Protection at the E5 tier).
What Office 365 E3 / E5 includes
- Exchange Online, SharePoint, OneDrive, Teams at the enterprise tier.
- The desktop Office apps.
- Basic Purview retention, DLP, and audit (deeper features at E5).
- No Windows Enterprise use rights, no Intune, no Entra ID paid tier.
What Microsoft 365 E3 / E5 adds on top
- Windows 10/11 Enterprise E3 or E5 use rights.
- Microsoft Intune for device and app management.
- Entra ID P1 (E3) or P2 (E5) for Conditional Access and Identity Protection.
- At E5: Defender for Endpoint Plan 2, Purview eDiscovery Premium, Advanced Audit, PIM, access reviews, Power BI Pro.
Business Standard and Business Premium are the SMB equivalents up to 300 seats — Business Premium is closest to Microsoft 365 E3 in shape but with a small-business ceiling and slightly different security-add-on eligibility.
Read next
- Microsoft 365 E3 vs E5 — what's worth the upgrade— A practical comparison of Microsoft 365 E3 and E5 plans — what E5 adds, where the value sits, and step-up patterns.
- Business Premium vs Microsoft 365 E3— Business Premium vs Microsoft 365 E3: Premium wins on security for less money, E3 wins on mailboxes, Windows, and scale. How to choose, and how to mix them.
- Microsoft 365 licensing models explained— How Microsoft 365 is sold — direct, CSP, EA, MCA, NCE — and which model fits which organisation.