Microsoft 365 E5 Security and E5 Compliance Add-Ons vs Full E5: The Math for an E3 Tenant

Microsoft's enterprise security suites page (opened 27 September 2026) lists the Microsoft Defender Suite as "previously Microsoft 365 E5 Security" and the Microsoft Purview Suite as "previously Microsoft 365 E5 Compliance." Third-party licensing reports date the rename to 1 October 2025 and say the contents did not change (as reported by SAMexpert and Mister Cloud Tech in October 2025; we could not open those pages, so verify). Both suites require Microsoft 365 E3, or Office 365 E3 with Enterprise Mobility + Security E3. The three smaller compliance suites kept their names on the price list: Microsoft 365 E5 Information Protection and Governance, Microsoft 365 E5 Insider Risk Management, and Microsoft 365 E5 eDiscovery and Audit. Business Premium tenants have their own editions, the Microsoft Defender Suite for Business Premium (Microsoft Learn, September 2025) and a Microsoft Purview Suite for Business Premium (Microsoft's Purview licensing guidance), which are outside this article's E3 scope.

Microsoft Defender Suite (the old E5 Security): Microsoft Defender XDR, Defender for Endpoint Plan 2, Defender for Identity, Defender for Office 365 Plan 2, Defender for Cloud Apps and Microsoft Entra ID P2. Our Defender for Business versus Plan 1 versus Plan 2 article explains the endpoint step, and Entra ID P1 vs P2 the identity step.

Microsoft Purview Suite (the old E5 Compliance): data loss prevention including endpoint and Teams chat, information protection with automatic labeling, insider risk management, eDiscovery (Premium) and Audit (Premium), communication compliance, data lifecycle and records management, Compliance Manager, and protection for Microsoft 365 Copilot data.

The three mini-suites, from Microsoft's Purview licensing guidance (opened 27 September 2026):

• E5 Information Protection and Governance: information protection, DLP for Teams chats, endpoint DLP, data lifecycle and records management, advanced message encryption, Defender for Cloud Apps, Customer Key and Customer Lockbox. Our Purview DLP starter article shows which policies need it.
• E5 Insider Risk Management: insider risk management, communication compliance, privileged access management, information barriers and data connectors.
• E5 eDiscovery and Audit: eDiscovery (Premium) and Audit (Premium).

Single-product step-ups on the price list for an E3 base: Defender for Endpoint P2 Add On for Microsoft 365 E3, Entra P2 Add On, and Defender for Office 365 P2 Add On. They cover three of the Defender Suite's five products; Defender for Identity and Defender for Cloud Apps have no E3 step-up on our sheet.

All figures are Microsoft list price, September 2026 price list, annual commitment, per user per year, with the monthly equivalent in brackets.

• Microsoft 365 E3: $468.00 ($39.00). Microsoft 365 E3 (no Teams): $365.40.
• Microsoft 365 E5: $720.00 ($60.00). Microsoft 365 E5 (no Teams): $617.40.
• Microsoft 365 E5 Information Protection and Governance: $84.00 ($7.00).
• Microsoft 365 E5 Insider Risk Management: $72.00 ($6.00).
• Microsoft 365 E5 eDiscovery and Audit: $72.00 ($6.00).
• Defender for Endpoint P2 Add On for E3: $36.00. Entra P2 Add On: $36.00. Defender for Office 365 P2 Add On: $36.00 ($3.00 each).

Not on the sheet: the Microsoft Defender Suite, the Microsoft Purview Suite and their Business Premium editions. We quote those on request against the price list of the month you order, and we do not print a number we cannot source. The 2026 price and packaging changes article explains why the sheet moves.

Per user per year, the gap between E3 and E5 is $252.00. Everything below asks how much of that gap the add-ons close, and what E5 still holds back.

Compliance first. The three mini-suites together cost $228.00 per user per year ($84.00 + $72.00 + $72.00). E3 plus all three is $696.00, only $24.00 under full E5. For 100 users: E3 $46,800; E3 plus the three mini-suites $69,600; E5 $72,000. For 300 users: $140,400; $208,800; $216,000. A tenant that needs all three compliance suites for everyone is $2,400 (100 users) or $7,200 (300 users) a year away from E5, and E5 also brings the Defender Suite, Teams Phone Standard and Power BI Pro. Buy E5.

One mini-suite. Most firms need one, usually Information Protection and Governance for endpoint and Teams DLP. E3 plus that suite is $552.00 per user per year: $55,200 for 100 users and $165,600 for 300, against E5 at $72,000 and $216,000. The saving is $16,800 or $50,400 a year, and it is real if the security side is already handled or not needed.

Security by step-ups. E3 plus the three E3 add-ons on the sheet (Endpoint P2, Entra P2, Office 365 P2) is $576.00 per user per year: $57,600 for 100 users, $172,800 for 300. That buys hunting and retention, PIM and Identity Protection, and Safe Links with automated investigation, but not Defender for Identity or Defender for Cloud Apps. The full Defender Suite is quoted on request; ask for it side by side with these three.

Mixed populations. The add-ons are per user, so license the people who need them. A 100-user tenant where 20 users need the full compliance set pays E3 for all plus three mini-suites for 20: $46,800 + $4,560 = $51,360. Moving those 20 to E5 instead costs $14,400 + $37,440 = $51,840, a difference of $480 a year, and the E5 users also get the Defender Suite, Teams Phone Standard and Power BI Pro. Below roughly a quarter of the population, mix; above it, run the whole-tenant numbers again. The plan optimizer does this per role.

Microsoft's own Microsoft 365 enterprise overview (Microsoft Learn, ms.date 18 November 2025) describes E5 as everything in E3 "plus advanced security, voice, and data analysis tools," which in the standard SKU means Teams Phone Standard and Power BI Pro (our E3 vs E5 article lists both; the exact contents depend on the SKU and region). Teams Phone Standard is on the sheet at $120.00 per user per year (Microsoft list price, September 2026 price list). Power BI Pro is not, so it stays a word here.

The arithmetic changes for a user who needs a phone. E3 plus Teams Phone Standard is $588.00; add one compliance mini-suite and it is $672.00; add all three and it is $816.00, which is $96.00 more than E5. So for any E3 user who needs Teams Phone Standard plus more than one E5 capability, E5 is the lower number before the Defender Suite is even counted. Calling plans and Operator Connect minutes are separate and metered by Microsoft or the carrier in either case. The E1 vs E3 vs Microsoft 365 E3 article covers the lower rungs, and the no-Teams SKUs keep the same $252.00 gap ($365.40 to $617.40) for tenants that license Teams separately.

Is the Microsoft 365 E5 Security add-on still available?

Yes, under the name Microsoft Defender Suite. Microsoft's suites page lists it as "previously Microsoft 365 E5 Security" with the same five products plus Defender XDR, and it still requires Microsoft 365 E3 or Office 365 E3 with EMS E3. It is not on our September 2026 price sheet, so we quote it on request.

What is included in Microsoft 365 E5 Compliance?

The suite is now the Microsoft Purview Suite: DLP including endpoint and Teams chat, information protection, insider risk management, eDiscovery and Audit (Premium), communication compliance, lifecycle and records management, Compliance Manager, and Copilot data protection. The three mini-suites split it into Information Protection and Governance, Insider Risk Management, and eDiscovery and Audit.

Can I buy E5 Compliance for only some users?

Yes. The suites and mini-suites are per-user add-ons on an E3 base, so a tenant can hold E3 for everyone and add a suite for the users whose data, devices or investigations need it. Scope the Purview policies to those users, and confirm the current per-user scoping rule for each feature on Microsoft Learn.

Is E3 plus E5 Security cheaper than E5?

Sometimes. The three single-product step-ups on the sheet take an E3 user to $576.00 per user per year against $720.00 for E5, but leave out Defender for Identity and Defender for Cloud Apps, and E5 also carries the Purview Suite, Teams Phone Standard and Power BI Pro. Compare the Defender Suite quote with those three, then count what else E5 replaces.

• Microsoft, Enterprise security suites pricing page (opened 27 September 2026): Microsoft Defender Suite "previously Microsoft 365 E5 Security", Microsoft Purview Suite "previously Microsoft 365 E5 Compliance", contents and the Microsoft 365 E3 prerequisite
• Microsoft, "Microsoft Purview licensing guidance" (microsoft.com/licensing, opened 27 September 2026): contents of the E5 Information Protection and Governance, E5 Insider Risk Management and E5 eDiscovery and Audit add-ons; the Purview Suite for Business Premium
• Microsoft Learn, "Microsoft 365 for enterprise overview" (ms.date 18 November 2025; opened via the MicrosoftDocs GitHub source): E5 includes the Defender Suite, the Purview Suite and "advanced security, voice, and data analysis tools"
• Microsoft Learn, "Add Microsoft Defender Suite for Business Premium to your subscription" (ms.date 24 September 2025; opened via the MicrosoftDocs GitHub source)
• SAMexpert and Mister Cloud Tech, October 2025 reports of the 1 October 2025 rename (not opened from this environment; as summarized in search results on 27 September 2026; verify)
• Microsoft, Commercial price list, September 2026 (our CSP price sheet; every list price above)
• IT Partner blog: microsoft-365-e3-vs-e5-upgrade-cost-2026; office-365-e1-vs-e3-vs-microsoft-365-e3-which-enterprise-plan; entra-id-p1-vs-p2-conditional-access-pim-identity-protection-compliance