Subscription email and unsubscribe

Use essential only for messages required to provide the requested service, transactional for direct transactions and subscription for optional lifecycle or marketing content.

Configure topics

Create a topic with a stable lowercase ID, name, description and default (opt_in or opt_out). IDs match [a-z0-9][a-z0-9._-]{1,63}. Archive a topic instead of reusing it for another purpose. Enable the Runtime subscription policy and managed mode when CFsend should provide preference/unsubscribe handling.

Send safely

Set messageClass: "subscription" and subscriptionTopicId on direct sends or Automation Send nodes. Campaigns also apply suppressions and preferences. The Runtime checks at send time; audience membership never overrides an unsubscribe.

{"message_class":"subscription","subscription_topic_id":"product.updates"}

Test the unsubscribe path and a second send to the same address before launch. Preferences represent recipient choice; bounce/complaint suppressions separately protect delivery reputation.