Microsoft 365 Licence: Proven Guide to Avoid Overpaying
Business Premium, E3 and E5 are not small, medium and large versions of the same product. Business Premium caps at 300 seats but ships a security stack that E3 quietly drops — moving up a tier can remove your email threat protection and endpoint detection unless you buy them back. This guide sets out what each plan genuinely includes, the three-year cost spread across fifty users, the E3 plus E5 Security route most buyers never hear about, why mixing tiers beats licensing everyone identically, and the buying terms that decide what the subscription really costs at renewal.
