Microsoft 365 Phone System
Part of Teams Phone
Teams Phone Included in 38 licenses
Microsoft 365
Microsoft 365 E5 Microsoft 365 E3 plus the full Defender security suite, Purview compliance stack, and advanced analytics — the top Microsoft 365 Enterprise tier; no seat cap.
Microsoft 365 E7 Microsoft 365 E5 plus additional advanced security add-ons bundled into a single SKU — Microsoft's newest, highest Enterprise tier.
Office 365
Office 365 E5 Office 365 E3 plus advanced security, compliance, and voice (Teams Phone, Audio Conferencing) — the top Office-only Enterprise tier; no seat cap.