Microsoft 365 E3 vs E5: Full Comparison for Enterprise Buyers (2026 Pricing)

What E3 and E5 Share: The Common Foundation

Before examining the differences, it is worth grounding the comparison in what E3 and E5 share. Both plans include the full Microsoft 365 productivity stack: desktop Office applications across Word, Excel, PowerPoint, Outlook, Access, and Publisher for up to five devices per user; Exchange Online with 100 GB mailboxes and unlimited archiving; SharePoint Online; Microsoft Teams; OneDrive with 1 TB base storage; and Yammer. Both include Windows 11 Enterprise E3 licensing, enabling the enterprise OS management and security features that distinguish it from consumer Windows. Both provide Microsoft Intune for device management, Entra ID P1 for conditional access and MFA, and basic Microsoft Purview DLP.

From July 2026, both E3 and E5 also include Defender for Office 365 Plan 1, providing anti-phishing, safe attachments, and safe links for Exchange Online. This previously required a separate add-on on E3, and its inclusion in the base E3 price is a meaningful security improvement at the updated pricing.

The shared foundation means that for the majority of knowledge workers — those whose security and compliance requirements are met by this baseline — E3 is fully sufficient. The challenge for procurement teams is identifying which users in their workforce genuinely require what E5 adds beyond this foundation.

What E5 Adds: The $21 Premium Itemised

E5's additional capabilities fall into five domains: advanced security, advanced compliance and eDiscovery, identity protection, voice and communications, and analytics. Understanding each domain helps determine which users drive the E5 requirement.

Advanced Security: The Defender Suite

E5's most material security additions are Defender for Endpoint Plan 2, Defender for Identity, and Defender for Cloud Apps. Defender for Endpoint P2 extends beyond the P1 included in Business Premium to add threat intelligence, endpoint detection and response (EDR), attack surface reduction, automated investigation and remediation, and Microsoft Threat Experts. For organisations with a security operations centre (SOC) or significant managed security service provider (MSSP) engagement, Defender for Endpoint P2 is material.

Defender for Identity provides Active Directory-based threat detection, identifying lateral movement, privilege escalation, and credential theft in on-premises and hybrid AD environments. This is essential for organisations with complex Active Directory configurations and is not available in E3. Defender for Cloud Apps provides a Cloud Access Security Broker (CASB) function — visibility into SaaS application usage, shadow IT discovery, and policy enforcement across cloud applications, both Microsoft and third-party. These three additions together constitute the foundation of Microsoft's XDR capability, and together they justify a meaningful portion of the E5 security premium for security-conscious organisations.

Entra ID P2: Advanced Identity Protection

E5 upgrades Entra ID from P1 (included in E3) to P2, adding Privileged Identity Management (PIM), Identity Protection, and Entra ID Access Reviews. PIM provides just-in-time privileged access, requiring elevated role holders to activate their privileges on demand rather than holding them permanently — materially reducing the attack surface from compromised administrator accounts. Identity Protection provides risk-based conditional access, automatically enforcing MFA or blocking sign-ins based on detected anomalies. For organisations with significant privileged access management requirements or regulated identity governance obligations, Entra ID P2 is not optional. It is a compliance necessity.

Advanced Compliance: Purview and eDiscovery

E5 includes the full Microsoft Purview compliance suite: eDiscovery Premium (with predictive coding, machine learning classification, and custodian management), Insider Risk Management, Communication Compliance, Advanced Audit (longer retention of audit logs, higher-value audit events), and Customer Lockbox. These capabilities are required for organisations with legal hold obligations beyond the standard eDiscovery Standard capability in E3, organisations subject to regulatory requirements for communications surveillance (FINRA, MiFID II, Dodd-Frank), and organisations managing insider risk programmes.

Not every user in an organisation subject to these regulations requires the full Purview E5 stack. Legal hold and eDiscovery obligations typically concentrate in legal and compliance roles. Communications surveillance requirements apply to regulated employees (financial advisers, traders, healthcare practitioners) rather than the entire workforce. Targeted E5 Compliance add-on licensing for those roles is often more cost-effective than blanket E5 deployment.

Microsoft Teams Phone and Audio Conferencing

E5 includes the Microsoft Teams Phone System add-on and Audio Conferencing, enabling PSTN calling and dial-in conference access through Teams. For organisations that have adopted Teams as their primary communications platform and are planning to replace traditional telephony with Teams Phone, this inclusion makes E5 more attractive relative to E3 plus the Teams Phone add-on ($8 per user per month) and Audio Conferencing add-on ($4 per user per month). For organisations not yet committed to Teams Phone, these features are included overhead at the E5 price point.

Power BI Pro

E5 includes Power BI Pro, Microsoft's self-service business intelligence platform. At $10 per user per month as a standalone licence, Power BI Pro adds a meaningful value component for organisations with significant analytics requirements. For organisations where only a subset of users require Power BI Pro access — analysts, finance teams, business intelligence roles — targeted Power BI Pro licensing on an E3 base is less expensive than blanket E5 deployment.

The Blanket E5 Upgrade Trap

Microsoft's renewal motion for E3 customers consistently pushes toward blanket E5 adoption. The commercial rationale for Microsoft is straightforward: upgrading 10,000 users from E3 to E5 generates an additional $2.52 million per year in recurring revenue from that single customer. The rationale for the buyer is less straightforward.

In practice, the genuine E5 requirement typically concentrates in specific roles. Security operations teams need Defender for Endpoint P2 and Defender for Identity. IT administrators need Entra ID P2 and PIM. Legal and compliance teams need eDiscovery Premium and Insider Risk Management. Finance and trading teams subject to communications surveillance need Communication Compliance. Senior executives may need Customer Lockbox. For most other knowledge workers, E3 provides all the capability they will use.

The financially optimal approach is a tiered deployment: E3 for the majority of knowledge workers, E5 add-ons for specific capability domains targeting the roles that require them, and F3 for frontline workers who do not need the full knowledge worker stack. This segmented approach consistently delivers 20 to 35 percent lower annual Microsoft spend than blanket E5 deployment.

E5 Add-Ons vs Full E5: The Cost Comparison

Microsoft offers E5 Security ($12 per user per month) and E5 Compliance ($12 per user per month) as targeted add-ons on an E3 base, allowing organisations to layer specific E5 capabilities without paying for the full $21 per user per month E5 premium. This provides significant flexibility:

• E3 + E5 Security: $39 + $12 = $51 per user per month. Includes all Defender capabilities and Entra ID P2. Misses eDiscovery Premium, Insider Risk, Teams Phone, Power BI Pro.
• E3 + E5 Compliance: $39 + $12 = $51 per user per month. Includes eDiscovery Premium, Insider Risk, Communication Compliance. Misses Defender P2, Entra ID P2, Teams Phone, Power BI Pro.
• E3 + E5 Security + E5 Compliance: $39 + $12 + $12 = $63 per user per month. Provides the full security and compliance capability of E5 for $3 more than E5. Worth evaluating only if the organisation does not need Teams Phone or Power BI Pro.
• Full E5: $60 per user per month. Includes everything including Teams Phone, Audio Conferencing, and Power BI Pro.

The arithmetic suggests that if an organisation needs both E5 Security and E5 Compliance capabilities but not Teams Phone or Power BI Pro, the add-on approach costs $3 more than full E5. In that scenario, full E5 is preferable. But if only one of the two E5 capability domains is required — which is common — targeted add-on licensing saves $9 per user per month versus full E5.

Where E7 Sits Above E5 in 2026

It is important to note that the Microsoft 365 SKU stack does not stop at E5. Microsoft 365 E7, available from May 2026 at $99 per user per month, is the new top-tier enterprise SKU positioned above E5. E7 bundles E5 together with Microsoft 365 Copilot, Agent 365 (AI governance), and the Microsoft Entra Suite into a single subscription. Microsoft field teams are actively positioning E5 customers toward E7 at renewal, and understanding E7's value proposition independently is essential before accepting that conversation.

For organisations evaluating the E3-to-E5 upgrade, the existence of E7 adds a third consideration: whether the upgrade path should be E3 → E5, or E3 → E5 → E7 in a phased approach, or E3 → E7 directly for AI-forward organisations that have already committed to Copilot. The M365 E7 Complete Guide covers this decision framework in detail.

Decision Framework: E3 or E5?

The following criteria indicate that E5 (or E5 add-ons) is the right choice for specific users or the entire organisation. E5 is genuinely justified when the organisation faces regulatory compliance obligations requiring eDiscovery Premium, Insider Risk Management, or Communications Compliance; when the security posture requires XDR-level threat detection and response with Defender for Endpoint P2 and Defender for Identity; when privileged access management via Entra ID P2 PIM is required to meet security or compliance standards; when the organisation has committed to Teams Phone as its PSTN replacement strategy; or when Power BI Pro is required for a significant proportion of users.

E3 is the correct choice when none of those conditions apply across the user population, or when they apply only to a subset of roles. For a typical enterprise, this means E5 is the right SKU for security operations, IT administration, legal and compliance, and regulated financial or healthcare roles — not necessarily for the entire workforce. Running a role-by-role analysis before the renewal conversation with Microsoft's field team is the most effective single action to protect your licensing spend.