Email Blacklist Checker

How senders end up blacklisted

Spam-trap hits, sudden volume spikes from cold domains, high complaint rates, or simply sharing infrastructure with a bad sender. For outbound teams the most common trigger is ramping new domains too fast without warmup.

What to do if you're listed

1. Stop sending from the affected domain/IP immediately — continued volume extends the listing.
2. Find the cause: check bounce logs, complaint rates, and whether an ESP neighbor got you listed.
3. Request delisting at the list's site (Spamhaus and Barracuda have removal forms; some lists auto-expire).
4. Fix the root cause before resuming, or you'll be re-listed with longer duration.

FAQ

Which blacklists actually matter?

Spamhaus (ZEN for IPs, DBL for domains) affects the most inboxes by far. Barracuda and SpamCop are used by many corporate filters. Others matter less individually but signal reputation trends.

My IP is my ESP's shared IP — should I still check?

Yes. A listed shared IP hurts everyone on it, and it's a signal to move pools or providers.