Microsoft 365 
Microsoft 365 E3 is Microsoft’s foundational enterprise plan, combining the complete Office 365 E3 suite with Windows 11 Enterprise upgrade rights and enterprise-grade identity and device management. It is designed for organisations with more than 300 users or those that need advanced compliance and legal discovery tools.
What’s Included
- Full Office desktop apps — Word, Excel, PowerPoint, Outlook, OneNote, Access, and Publisher on up to 5 PCs/Macs and 5 mobile devices per user.
- Exchange Online Plan 2 — 100 GB mailbox per user (double the Business plans), plus In-Place Archive with unlimited storage and litigation hold.
- SharePoint Online Plan 2 — Includes advanced search, eDiscovery, and content compliance features.
- OneDrive for Business Plan 2 — 1 TB storage with unlimited archive. Advanced auditing and data loss prevention for files.
- Teams — Full collaboration suite with audio conferencing available as an add-on.
- Microsoft Purview Compliance — eDiscovery (search, hold, export), Audit (Standard), Content Search, Communication Compliance basics, and Records Management to meet legal and regulatory requirements.
- Azure AD Premium P1 (Microsoft Entra ID P1) — Conditional Access, group-based licensing, self-service password reset, hybrid identity (Azure AD Connect).
- Microsoft Intune — Full MDM and MAM for all devices, including Windows Autopilot deployment.
- Windows 11 Enterprise upgrade rights — Upgrade Windows 10/11 Pro devices to Enterprise edition. Includes features like AppLocker, Windows Credential Guard, and DirectAccess.
- Microsoft Defender Antivirus — Built-in endpoint protection. Note: E3 does not include Defender for Endpoint P1/P2 — add separately if needed.
Storage & Limits
- Exchange mailbox: 100 GB per user + unlimited archive
- OneDrive: 1 TB per user
- Office installs: 5 PCs/Macs + 5 phones + 5 tablets per user
- No maximum user limit
Ideal For
Enterprise organisations (300+ users) that need Windows Enterprise licensing, advanced compliance and eDiscovery tools, and large mailboxes with litigation hold. Also ideal for businesses in regulated industries — legal, finance, healthcare — that must meet audit and data retention requirements.
Keys Locker CSP Guarantee
- Genuine Microsoft CSP licence — provisioned directly through the official Microsoft partner channel
- 99.9% uptime SLA — Microsoft-backed service level agreement for all Microsoft 365 services
- Instant provisioning — subscription activated within minutes of payment confirming
- 7-day money-back guarantee — full refund if not provisioned or unused within 7 days
- Flexible cancellation — cancel monthly plans anytime; annual plans cancel at end of term
- 24/7 partner support — our team escalates issues directly to Microsoft on your behalf
- Scale up or down anytime — add or remove seats mid-cycle with no penalty
