Microsoft 365 Business Premium vs E5: Which is Right for Your Business?
Both plans include advanced security, compliance, and productivity tools — but they target very different business sizes and requirements. This guide breaks down every key difference to help you choose.
Key Facts
Quick answer
For UK SMEs with fewer than 300 users, M365 Business Premium is the right licence — it includes Defender for Business, Intune, Entra ID P1, and Conditional Access at a price that makes E5 unnecessary. Only consider E5 if you need built-in SIEM (Sentinel), Teams Phone, Defender XDR, or advanced eDiscovery for legal or compliance obligations. E5 is an enterprise licence at enterprise cost; Business Premium is the SME security sweet spot.
Feature-by-Feature Comparison
Key capabilities across security, compliance, productivity, and identity — compared side by side.
| Feature | Business PremiumFrom £16.90/user/moRecommended | E3From £24.40/user/mo | E5From £37.50/user/mo |
|---|---|---|---|
| Microsoft 365 Apps (desktop) | |||
| Exchange Online (50GB mailbox) | |||
| SharePoint & OneDrive (1TB) | |||
| Teams Phone System | Add-on | ||
| Microsoft Entra ID P1 | |||
| Microsoft Entra ID P2 | |||
| Conditional Access | |||
| Microsoft Defender for Business | |||
| Microsoft Defender for Endpoint P2 | Add-on | ||
| Microsoft Defender for Office 365 P2 | |||
| Microsoft Defender for Cloud Apps | |||
| Microsoft Sentinel (SIEM) | Add-on | ||
| Microsoft Purview DLP | |||
| Microsoft Purview eDiscovery Premium | |||
| Intune (MDM/MAM) | |||
| Max users per tenant | 300 | Unlimited | Unlimited |
| Privileged Identity Management | |||
| Power BI Pro |
Prices correct as of March 2026 (annual commitment). AMVIA customers receive preferential Microsoft CSP pricing. Add-on pricing available on request.
When to Choose Each Plan
The right licence depends on your headcount, security requirements, and compliance obligations.
Choose Business Premium if...
You have under 300 users, need strong endpoint security and Conditional Access, and don't require advanced SIEM, eDiscovery, or Teams Phone. The best-value plan for most UK SMEs.
Choose E3 if...
You have over 300 users, need enterprise compliance features (eDiscovery, audit logs, legal hold), or require enterprise-grade identity management. Security must be added via add-ons.
Choose E5 if...
You operate in a regulated industry, need a built-in SIEM (Sentinel), require Teams Phone, demand maximum identity protection (Entra P2 + PIM), or need Defender XDR across email, endpoint, and cloud apps.
Cost-Benefit Summary
For a 50-user business, Business Premium costs approximately £10,140/year. Adding equivalent E5 security capabilities through individual E3 add-ons would exceed £18,000/year. Business Premium delivers the better security ROI for sub-300 user businesses — and AMVIA's managed M365 service is included at no additional cost on our IT support plans.
See full M365 pricing guideThe AMVIA Recommendation
The AMVIA Recommendation
For UK SMEs under 300 users, M365 Business Premium is the right licence tier. It includes Defender for Business (EDR-level endpoint protection), Intune (device management), Azure AD P1 (Conditional Access), and Defender for Office 365 — an integrated security stack at approximately £16.90 per user per month. AMVIA can audit your current licences and ensure you are getting full value.
Get a Free M365 Licence ReviewFrequently Asked Questions
Business Premium includes Defender for Business, which is a simplified EDR solution designed specifically for SMEs. E5 includes the more advanced Defender for Endpoint P2, Defender for Office 365 P2, and Defender for Cloud Apps. However, for businesses under 300 users, Business Premium's security stack covers the most critical threat vectors at roughly half the per-user cost.
E5 is justified when you need Teams Phone System built in, advanced eDiscovery for legal hold, Entra ID P2 with Privileged Identity Management, or Power BI Pro. Microsoft 365 has over 400 million paid commercial seats (Microsoft FY2025), and the vast majority of SME organisations operate comfortably on Business Premium without requiring E5-tier features.
Yes. Microsoft allows add-on licences for specific capabilities such as Teams Phone, Defender for Endpoint P2, or Azure AD P2. For a 50-user business, selectively adding one or two E5 features to Business Premium is often significantly cheaper than upgrading every user to the full E5 licence at £37.50 per user per month.
Yes. Business Premium is capped at 300 users per tenant. Once you exceed this threshold, you must move to enterprise licensing — typically E3 plus security add-ons, or E5. With the average cost of the most disruptive breach at £3,550 (DSIT 2025), planning your licence migration early ensures no security gaps emerge during the transition.
Get Expert M365 Licence Advice
AMVIA's Microsoft-certified engineers will review your current licences, identify over-provisioning or gaps, and recommend the most cost-effective configuration for your business.
Related Resources
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UK pricing guide for managed cybersecurity services
M365 Business Premium vs Standard
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Microsoft 365 Security Audit
Get your M365 tenant security assessed
How to Set Up MFA in Microsoft 365
Step-by-step MFA setup guide