Every send's footer includes a {{unsubscribe_url}} merge tag pointing at a real hosted page. It combines a one-click unsubscribe — account-wide by default, or per-topic if you've set up mail topics — with a second form for correcting or deleting the recipient's data. That second form routes to you as a support ticket rather than deleting anything automatically.
A compliant unsubscribe link isn't a mailto: address someone has to write in by hand — it's a page that actually does something the moment it's confirmed.
One click, or just one topic
By default, confirming unsubscribe on the hosted page blocks that address across every project you send from, not just the campaign it came from. It's checked automatically before every future send, with a badge and a Resubscribe action visible in Contacts afterward.
If blanket unsubscribe is too blunt, name a few mail topics under Settings ("Product updates," "Promotions," a weekly digest) and assign a project to one. That project's unsubscribe page then shows a checkbox per topic instead of a single button, so a recipient can mute promotions while staying reachable for order receipts and anything else they still want. A project with no topic assigned keeps the plain all-or-nothing page — nothing changes until you opt in.
Data requests become a ticket, not a delete button
The same hosted page's "Correct or delete your data" form submits as a badged Privacy request support ticket in your own inbox. A single click can't safely delete a contact row on its own — doing so could break response attribution or void an order's audit trail. It might also ignore a legal reason to retain the record. That judgment call stays with you as the controller.
Transactional mail plays by different rules
A send marked type: "transactional" (via the Send API) bypasses unsubscribe-suppression, since a receipt still needs to reach someone who opted out of marketing. It never bypasses bounce-suppression, though — that always applies.
Getting started
Keep the {{unsubscribe_url}} tag in your footer preset. Add mail topics under Settings if you want granular opt-outs, and review Privacy & data controls for handling recipient requests as they arrive in your ticket inbox.