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Blocklists
The modern handbook on Blocklists
Track the reputation lists that can stop mail from reaching the inbox and learn how delisting works.
By
Michael Ko & Matthew Whittaker
11 featured articles
1 hour 27 min read
Updated 17 Jun 2026
Spot reputation
problems before
they block the inbox.
Suped
The modern handbook on
Blocklists
Foundation
1
How email blacklists actually work: a simple guide
Learn how email blacklists and blocklists work, why listings happen, and how to check, fix, and prevent reputation issues.
9 min read
2
A guide to RBLs (real-time blackhole lists)
Learn how RBLs work, why IPs get listed, how blocklists affect delivery, and how to fix repeat listings.
10 min read
3
A guide to the different types of email blocklists
Understand the main types of email blocklists, how each blacklist affects delivery, and how to check and respond.
10 min read
Monitoring
4
What are the most important email blacklists to monitor and how do you check them?
Discover the most important email blacklists to monitor and learn how to effectively check your IP and domain status to maintain optimal email deliverability.
10 min read
5
Which email blocklists are most important for deliverability and how should they be prioritized?
Learn which email blocklists (blacklists) impact deliverability and use Suped for monitoring and mitigation to maintain a strong sender reputation.
10 min read
6
Spam traps: what they are and how they work
Spam traps are monitored email addresses that expose poor list hygiene, risky acquisition, and sender reputation issues.
9 min read
Major blocklists
7
Spamhaus ZEN Blocklist
Spamhaus ZEN combines four IP blocklists into one query to help filter spam and malicious traffic. Use Suped to monitor your standing on this blocklist.
3 min read
8
Spamhaus Domain Blocklist (DBL)
The Spamhaus DBL is a domain blocklist (blacklist) protecting against spam, phishing, fraud, and malware. Monitor your domain reputation with Suped.
3 min read
9
Barracuda Networks Barracuda Reputation Block List (BRBL)
The Barracuda Reputation Block List (BRBL) is a database of IP addresses with poor reputations, acting as a blacklist (or blocklist) for email senders.
3 min read
Delisting and recovery
10
How can I get delisted from Spamhaus?
Learn how to remove your domain or IP from Spamhaus blacklists (also known as blocklists). Follow these steps to identify, fix, and request removal.
11 min read
11
How to deal with UCEProtect listings and their aggressive practices?
Manage UCEProtect blocklist and blacklist issues. Learn delisting steps and best practices to maintain email deliverability with Suped.
9 min read
On this page
Foundation
Monitoring
Major blocklists
Delisting and recovery
Suped - DMARC monitoring
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1-12 articles
Next
Blocklists FAQs
Answers to common questions about email blocklists, monitoring, and delisting.
What is an email blocklist?
Do all blocklist listings hurt equally?
How do I know if a blocklist is affecting delivery?
How do I get delisted?
Can a shared IP blocklist listing affect me?
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Clear recommendations to improve email deliverability
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