Listed on Backscatterer? Your Server Is Bouncing Spam
Backscatterer doesn't list spammers. It lists mail servers that send bounces or auto-replies to forged sender addresses, which lands junk mail in innocent people's inboxes. Big providers get listed too.
Why Your Server Got Listed
Spammers forge sender addresses. If your server accepts a spam message first and bounces it later, or sends an out-of-office reply to it, that bounce goes to someone who never sent anything. Sender address verification callouts count too.
How to Fix It
Reject spam and unknown recipients during the SMTP conversation instead of accepting and bouncing later, keep auto-replies away from spam, and turn off sender callouts. Once it stops, the listing takes care of itself.
Free or Fast
Backscatterer removes an IP automatically four weeks after the last backscatter it sees, and every new incident restarts the clock. It also sells express delisting (89 CHF when we checked in September 2026), but it's never required, and the operator doesn't make exceptions on request. Check your IP on Backscatterer.
Spot It Before It Snowballs
Backscatter listings often mean a mail server setting nobody has looked at in years. Generator Labs checks your IPs against Backscatterer and 150+ other data sources and alerts you by email, Slack, SMS, or webhook when a listing appears. Free for your first host.
Frequently Asked Questions
About Backscatterer listings.
How long does a Backscatterer listing last?
Four weeks after the last backscatter, free. Each new incident resets the clock.
Do I have to pay?
No. Express delisting is optional.
Does a Backscatterer listing mean I sent spam?
No. It means your server sent bounces or auto-replies to forged addresses.
Other Blacklists
How to get off each of the blacklists that matter most.