Microsoft 365 Basics
Lesson 01Beginner5 min read

The tenant: what you're actually buying

Tenant, directory, subscriptions — what each is, how they relate, and where things go wrong.


When you "buy Microsoft 365" you actually create a tenant. The tenant is a dedicated instance of Entra ID (the directory) plus a set of subscriptions (the licenses) plus the data and configuration you put into it.

Three things, one bill

  • Tenant: the container. Has a unique ID and one or more domain names.
  • Directory (Entra ID): users, groups, devices, applications.
  • Subscriptions: what your users are licensed for (Exchange, Teams, Intune, etc.).

Where things go wrong

New admins create a second tenant for "testing" and then can't merge them. Tenants don't merge. Plan one tenant, use Conditional Access and admin units to carve up access inside it.

Next lesson

Licensing without losing your mind

F1, F3, E3, E5, EMS — what's actually included, what isn't, and the SKUs people forget.