Suppressionlist builder.
Merge your unsubscribes, bounces and customers into one do-not-contact list, then clean any new list against it before you send.
How it works
- Paste who to excludeUnsubscribes, bounces, customers
- Download the listEmails and whole domains
- Clean a new listOnly the safe addresses remain
Free, no sign-up. Runs in your browser. Nothing you type is sent anywhere.
The tool
Who must not get an email
Emails, or whole domains (for current customers or competitors). Nothing leaves your browser.
Your suppression list
Keeping a do-not-contact list.
What the result means, and how to fix what it finds.
Why you need one
Emailing someone who unsubscribed is the quickest way to a spam report, and in many countries it's against the law. Emailing an address that already bounced damages your domain again. Emailing your own customers a cold pitch is embarrassing. One list that covers all three, checked before every campaign, prevents all of it.
Emails and domains
Add individual addresses for unsubscribes and bounces. For customers and competitors, add the whole domain: anyone at that company is excluded, including people you haven't met yet. We tell the two apart automatically: anything with an @ is an address, anything else is a domain.
Check every new list
Paste a new list into the last box and we remove anyone on your suppression list, showing how many were taken out. Do this every time you add leads, even from a trusted source, because the same people turn up in different lists.
Keep it in your sending tool
A suppression list is only useful if your sending tool uses it on every campaign. Most tools have a blocklist or do-not-contact setting: upload this file there. Keep the master copy updated whenever someone unsubscribes or bounces.
What else belongs on the list
Beyond unsubscribes, bounces and customers, a few other groups are worth adding. People who replied 'not interested' should rest for months, or for good. Partners and investors deserve personal email, not a sequence. Your own team's addresses and your other domains keep test sends out of campaigns. Some senders also add their competitors' domains, and large free email providers when they sell only to businesses. Keep a note of why each entry was added and when, so you can tell later which ones can be lifted, such as an old 'not now' reply, and which never can. Review the list every few months.
In mailzy
Unsubscribes handled for you.
mailzy adds one-click unsubscribe to campaigns, keeps everyone who opts out off every future campaign, and stops sequences when someone replies.
Questions before you start.
Ask us on the chat if yours isn't here. A real person answers.
How do I exclude a whole company?
Add its domain without an @ (for example acme.com). Everyone at that domain is removed.
Is the list stored?
No. Everything runs in your browser. Download the file to keep it.
How long should I keep unsubscribes?
For good. An unsubscribe doesn't expire.
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