Leak alerts

New-Sender Alerts and One-Tap Block, Step by Step

On Plus and Pro, Emcognito emails you when a new company starts mailing one of your aliases, so a leaked address shows up the day it leaks. From your delivery log you can block that sender for one alias in one tap: later mail from that domain and its subdomains is stopped and shows as Blocked sender. Unblocking takes effect right away.

Updated 2026-10-05

1. Keep new-sender alerts on

Alerts are on by default for Plus and Pro, under Settings › Billing › Alerts. The first company an alias hears from is the one you gave it to, so it never triggers an alert; the second one does. The email names the new sender, shows its first message as proof, and has buttons to block that company or pause the alias.

The Alerts card in Emcognito settings with the New-sender alerts switch turned on — Settings › Billing › Alerts. Turn it off here if you would rather not get the emails.

2. Block a sender from the delivery log

Every message in your delivery log on Plus and Pro has a Block sender button. Tap it and Emcognito asks you to confirm, naming the whole domain it will block, including subdomains. The block applies to that one alias, so the same company can still reach any other alias you gave it.

A forwarded message in the Emcognito delivery log with Reply securely and Block sender buttons under it — Each message in the log carries Block sender.

The block confirmation reading Stop all mail from example.com (including mail.example.com) and its subdomains to this alias? with Block and Cancel buttons — The confirmation names the domain it will block, subdomains included.

3. See what was stopped

Mail from a blocked sender is not forwarded. It still appears in your delivery log, marked Blocked sender, so you can check what was stopped without it ever reaching your inbox.

Two delivery log entries for the same alias: the newer one marked Blocked sender, the older one marked Forwarded — After the block: the next message from that sender is marked Blocked sender.

4. Undo a block

Open the alias in the Command Center and tap its edit button. Blocked senders are listed at the bottom with an Unblock button. Unblocking takes effect right away; Save and Cancel in that dialog do not change it.

The Edit alias metadata dialog with a Blocked senders list showing example.com and an Unblock button — The alias's edit dialog lists its blocked senders, each with Unblock.

Frequently asked questions

Which plans include new-sender alerts and blocking?

Plus and Pro. On Free the Block sender button and the Alerts card are shown locked, and tapping either opens the Plus upgrade.

Does blocking a sender affect my other aliases?

No. A block applies to the one alias it was made on. Mail from that domain to your other aliases is forwarded as usual.

Why didn't I get an alert for the first message an alias received?

The first company an alias hears from is normally the one you gave it to, so it is not news. Alerts start with the second sender domain.

Can I pause an alias instead of blocking one sender?

Yes. The alert email has a button to pause the alias, and you can suspend any alias from your dashboard. Pausing stops all of its mail, not just one sender's.

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