Hello user831422 ,
Only active contacts are calculated into subscription costs. If a contact of yours is unsubscribed, then they won't be calculated into that. For more info on active vs inactive email contacts, see this support article.
Keep in mind that SMS and email are different subscriptions, so if a contact is subscribed to one but not the other, then that counts as an active contact for your billing. If a single contact is subscribed for both, that still only counts as one active contact for your billing. If they're unsubscribed for both, then they’d be inactive and wouldn't count toward your billing.
See also:
Billing FAQ
