Glossary
Email Blacklist — What It Is and How to Get Delisted
An email blacklist (also called a blocklist or DNSBL) is a real-time database of IP addresses and domains known to send spam. Mail servers query these lists when an email arrives — if your sending IP appears on a major blacklist like Spamhaus, your email may be rejected before SPF or DKIM is even checked.
Major Email Blacklists
- Spamhaus ZEN — most widely used, covers multiple Spamhaus lists
- SpamCop — crowd-sourced spam reports
- Barracuda — used by many corporate mail servers
- SORBS — aggregates multiple threat categories
How to Check If You're Blacklisted
Run DomainPreflight Email Deliverability with your sending IP — checks 10+ blacklists instantly.
How to Get Delisted
Fix the underlying issue first. Then submit a removal request at each list's website. Most removals take 24-72 hours.
Check your IP against major lists
Open Email Deliverability →FAQ
What is an email blacklist?
A database of IP addresses and domains known to send spam. Mail servers check these lists to decide whether to accept or reject incoming email.
How do I check if my IP is blacklisted?
Use DomainPreflight Email Deliverability — enter your sending IP and it checks 10+ major blacklists in seconds.
How long does blacklist removal take?
Spamhaus: 24-48 hours. SpamCop: auto-expires in 24-48 hours when spam stops. Barracuda: 12-24 hours after delisting request.