Start with bought against assigned
The simplest check is, for each Microsoft 365 subscription, how many seats were bought and how many are assigned to a user. The Microsoft 365 admin centre shows both. Seats bought but not assigned are the most obvious waste, and the easiest to remove.
Then look for licences that are assigned but not used
An assigned seat isn’t necessarily a used one. Look for:
- Accounts that are disabled but still hold a licence, often leavers.
- Accounts that haven’t signed in for a long time.
- Duplicate or test accounts that were licensed and forgotten.
A note on sign-in data
Last sign-in information comes from Entra ID, and it needs the Entra ID P1 or P2 licence in the tenant plus the right audit-log permission. If a client doesn’t have that, you can still compare bought with assigned and check for disabled accounts, but you won’t see last sign-in.
Price the waste
Multiply unused seats by the cost per seat per month, then by twelve. With made-up numbers: 5 unused seats at £15 a seat a month is £900 a year. If you buy through a distributor, use the price your client actually pays rather than a list price, so the figure matches their invoice.
Reclaim safely
- Confirm an account is genuinely unused before removing a licence, especially mailboxes with data.
- Check the commitment term. Annual commitments can limit when you’re able to reduce seats, so know the date you can act.
- Record what you changed, so the next review starts from facts.
Do it every month, not once
Licence waste comes back as people join, leave and change roles. A monthly check, or better, a register that updates itself, stops it building up again.
How Omnia Manage helps
Omnia Manage syncs each Microsoft 365 tenant, showing seats bought and assigned for every paid subscription and each licensed user’s licences, whether the account is enabled and their last sign-in where the tenant allows it. Unused seats are priced in pounds from the cost per seat on the licence, and they roll up into a licence waste total on your dashboard, with a renewal reminder before each renewal.