Salesforce bills Marketing Cloud on total number of Contacts within the system. I'd like to know what exactly is used to count these? Is this the Email Studio > All Subscribers list or the Contact Builder > All Contacts list?
When we have Marketing Cloud connector and synchronise the Contacts object, is this counted towards that number? (or only when they have been inserted into the All Subscribers / All Contacts list, as they are not done so automatically)
Well, the situation is complicated. So let's break it down:
All Contacts
Salesforce bills Marketing Cloud on total number of Contacts within the system. (...) Is this the Email Studio > All Subscribers list or the Contact Builder > All Contacts list?
As the Contact Definition and Count Determination states, the following objects are being automatically added:
Contacts are counted regardless of the fact if you tried to contact them or not - you can import contacts to lists making them billable without having sent anything to them.
When we have Marketing Cloud connector and synchronize the Contacts object, is this counted towards that number?
Yes, as stated above and in the documentation, not only all records of Contact object, but also Leads and users are being counted toward your limit. In the case you're using Person Accounts, the respective Contact records will be counted towards the limit.
What is used to count billable contacts?
Salesforce bills Marketing Cloud on total number of Contacts within the system. I'd like to know what exactly is used to count these? Is this the Email Studio > All Subscribers list or the Contact Builder > All Contacts list?
The main source of information for billing is actually not the All Contacts list - it is the Contact Counts Report that can be created in Analytics Builder > Reports.
The problem here is that you won't be able to see the list of contacts that will be considered billable by Salesforce - only the number is visible.
The problem with All Contacts
Why is the Contact Counts Report the main source of data for billing? Because the All Contacts list does not contain populations. I learned this from a support agent while trying to figure out why the Contact Counts report was showing higher numbers than All Contacts:
The number in All Contacts is the total number of all records in your contact table, except for those included in Populations
The agent also shared a link to the following article: Why is my All Contacts Count different than my Contacts Counts Report count which states that:
the Contacts Counts report available within the Reporting app might vary from this number. The Contacts Counts report also factors in the records within an account's Populations (formerly known as Root Data Extensions)
and that
If you need to find your Data Extensions that are Populations, these can be found in Contact Builder > Data Designer > Populations. This would need to be done in all Business Units in an Enterprise 2.0 account. If there are Root Data Extensions in the account, these will not show up in the Populations screen. One way for users to find all of the Data Extensions within a single MID that are either used as a Population or a Root would be utilizing this API call.
To emphasize this: if you can't find any populations visible in Contact Builder's Data Designer and the Contact Count report still says you are using populations, you need to do the API call in each of your BUs to find data extensions that are marked with "Use as Root" when viewing a DE in Contact Builder.
This setting will be checked in only one business unit and you need to uncheck that on that BU.
Eliot Harper signals how populations influence the contact count in his video called Contact Builder Populations in Salesforce Marketing Cloud:
Just remember that as explained in the documentation - a population is regarded as a contact database. This means that any record in the data extension that you use as a population, will qualify towards your contact count determination.
Final Contact Count
If you want to know for how many contacts are counted towards your limit, use the Contact Counts report in Analytics Builder.
If you want to know what contacts are counted towards your limit, you need to:
Later add the records from this table to all records that are stored in All Contacts - you can extract this info if you have Mobile Connect enabled in this way:
Contact Key is not nullSelect SubscriberKey from [Your MobileConnect list name from step 1](This process is a reverse-engineered from an article that shows how to remove unwanted customers: Permanently remove Contacts or Subscribers and associated data from Contact Builder)
TLDR:
Contact Count = All Contacts + all records in Populations (or root data extensions)
