When a client terminates an employee, that mailbox stops being a user and starts being a compliance obligation. The data still has to exist — for an employment dispute, a regulatory request, a discovery order — but nobody is generating new data in it and nobody is logging in.
Most backup platforms keep billing it as a user, because the billing model counts mailboxes rather than activity.
Seven years of a 500-seat client
Eight percent annual churn is unremarkable for a mid-size business. The effect on a backup bill is not obvious until it is written down, because the archived population accumulates while the active population stays flat.
The workaround, and what it costs
The usual response is an offboarding script: when a licence is removed, stop backing the mailbox up. It saves the money immediately and it is easy to justify, because the user is gone.
It trades a small recurring saving for the single scenario retention exists to cover. Wrongful-termination claims surface months after the exit. Regulatory requests arrive years later. In both cases the data you need is the data belonging to someone who is no longer employed — which is precisely what the script deleted.
The second-order cost is that the script becomes load-bearing. It has to run reliably across every tenant, stay correct as the licensing model changes, and be maintained by whoever inherits it. That is real engineering attached to a billing workaround.
Across your book, how many seats are billed at the full rate for people who left? The number is usually larger than expected because nothing surfaces it — the invoice shows a seat count, not a composition.
What automatic archiving does instead
The platform detects the unlicensed user, moves the seat to archived status, and bills it at half the active rate. The history is retained under your own retention policy rather than a fixed term set by us.
There is no script, no decision, and no window in which somebody has to remember. The margin stops eroding as a property of the billing model rather than as the outcome of a process somebody maintains.