Email Blacklist Check

What is Blacklist?

DNS-based blacklists (DNSBLs) are real-time databases of IP addresses and domains known or suspected of sending spam. When a mail server receives an email, it queries multiple DNSBLs to check if the sending IP is listed. If it is, the email may be blocked, quarantined, or penalised. Major lists like Spamhaus, Barracuda, and SORBS are consulted by millions of mail servers worldwide.

Why does it matter for email deliverability?

A single blacklist listing can cause your emails to bounce or land in spam for a significant portion of recipients — even if your SPF, DKIM, and DMARC are all configured correctly. Shared hosting and transactional email providers sometimes have IPs listed due to other tenants' behaviour, affecting all users on that IP. Knowing your listing status is essential to diagnosing unexplained delivery failures.

Common Blacklist Issues

• Shared IP listed due to another sender's spam activity on the same server
• IP listed after a spam complaint surge from a bulk email campaign
• Domain listed following a phishing incident or account compromise
• IP listed for sending to spam traps — often from purchased or outdated mailing lists
• Listing on Spamhaus PBL — dynamic IPs are listed by design and need to be unlisted for mail servers

How to Fix Blacklist Problems

First, identify which blacklists you're listed on (FixMyEmail checks all 20+ automatically). Each blacklist has its own removal process — most major ones like Spamhaus and Barracuda have self-serve delisting portals. Before requesting removal, fix the underlying cause: stop sending spam, clean your mailing list, rotate to a clean IP, or switch to a reputable transactional email provider. Removal from some lists (like Spamhaus XBL) happens automatically once the threat is resolved; others require manual application.