I'm working on a Marketing Cloud implementation and am confused around the limit of Contacts associated with the customer's edition of Marketing Cloud. The customer's "Contact" limit is 75,000. Does this also mean that the customer is limited to 75,000 subscribers?
It means that the contract was signed for 75000 Contacts - and if this amount is exceeded, Salesforce will bill the client for extra.
Do note that the amount of Contacts does not equal the amount of Subscribers in
AllSubscribers list. Contact in Marketing Cloud is a sendable record with a unique
Meaning if you set up Marketing Cloud Connect and decide to synchronise Contacts, Leads and Users, then each of these will count as a billable Contact for an example.
Definitely read up on Contact Definition and Count Determination to avoid nasty surprises.