Overview
Even with the cleanest data, sometimes a recipient ends up on a list twice, or a previous unsubscriber slips back in. The Duplicates and Unsubscribes section is where you tell the platform how to handle both before your communications go out the door.
You'll find three settings here. Two are simple toggles and one is a dropdown — together they cover deduplication on import, the unsubscribe headers required by bulk email providers, and what to do about people who've previously opted out.
These settings are configured per Application, so you can apply different rules depending on the type of communication you're sending.
To get there
- In the secondary navigation menu, click Applications to view a list of all available Applications.
- In the Application list view, double click the auto highlighted Application or click the Settings icon on the right hand side of the list view to open it.
- Click the Details tab and scroll to the Duplicates and Unsubscribes section.
Sending in bulk to Gmail or Yahoo addresses?
Make sure Add automatic unsubscribe headers is ticked. Both providers now require list-unsubscribe headers for bulk senders, and your emails may be filtered or blocked without them.
Remove duplicates
When this is ticked, the platform will check your import file for duplicate records and only send to the first instance of each. Anything after that gets skipped.
This is a useful safety net when your data comes from multiple sources or you're not sure whether a list has been deduplicated upstream. If you'd rather every record be treated as a separate send, leave it unticked.
- In the Duplicates and Unsubscribes section, tick Remove duplicates to enable deduplication on import.
Add automatic unsubscribe headers
This setting adds list-unsubscribe headers to your emails, which lets recipients click Unsubscribe directly from their inbox without opening the message. It's the kind of thing most people don't notice until it's missing — and then their email gets blocked.
It's a requirement for bulk senders to major providers like Gmail and Yahoo, so unless you've got a specific reason to turn it off, leave it ticked.
- In the Duplicates and Unsubscribes section, tick Add automatic unsubscribe headers.
Remove previous unsubscribes
This dropdown decides whether the platform should automatically filter out anyone who's already unsubscribed before sending. You've got four options to choose from, each one widening the net a little further.
- Don't remove — previous unsubscribes will still receive the communication. Use this when you need to send something everyone must receive (e.g. a critical service notice).
- From this application only — skip recipients who've unsubscribed from this Application before. A good fit when each Application represents a distinct type of communication and an opt-out from one shouldn't affect the others.
- From all applications in category — skip anyone who's unsubscribed from any Application in the same category. Handy when your categories group related communications (like all marketing sends) and an opt-out should apply across the group.
- From all applications — the broadest option. Skip anyone who's ever unsubscribed from any Application on the platform. Use this when you want a single opt-out to mean "don't contact me at all".
- In the Duplicates and Unsubscribes section, open the Remove previous unsubscribes dropdown and select the option that matches how you want unsubscribes to apply.
That's it — your duplicates and unsubscribes are now handled automatically every time you send from this Application. You can come back and adjust these settings any time your rules change.