How does emarsys attribute unsubscribe to an email campaign when we use external unsubscribe page?

[SAPSupport]

How does emarsys attribute unsubscribe to an email campaign when we use external unsubscribe page? We have a Sitecore form that will update records of user in CDC which will in turn update user profile in emarsys but when analyzing the campaigns, how will emarsys attribute unsubscribe to specific campaigns?

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[SAPSupport · Accepted solution]

The Unsubscribes are counted automatically by Emarsys only when List-unsubscribe or the standard forms/unsubscribe solution are used. To attribute unsubscribe data from external unsubscribe pages to an Emarsys campaign, you must use the API entity Unsubscribe a Contact from an Email Campaign | Emarsys Core API Reference. This is used for this exact purpose — attribute a contact unsubscribe to a campaign, as it doesn't actually unsubscribe the contact but rather tell Emarsys that the contact has been unsubscribed on that specific campaign that is sent on the API call.

To fully integrate the custom unsubscribe solution to Emarsys, you must ensure that a call to this API is made with the contact and email campaign details as specified in the documentation shared above.