Spamhaus Project
Spamhaus SBL
Manually curated list of verified spam sources and snowshoe operators.
- DNS zone
sbl.spamhaus.org- Target
- IP addresses
- Severity
- high
What it lists
The Spamhaus Block List (SBL) is a manually maintained list of IPs and netblocks operated by confirmed spam senders, including snowshoe operators rotating across many IPs. Listings are evidenced and reviewed by Spamhaus analysts.
Who gets listed
Confirmed spam operations, networks that ignore abuse reports, and providers that knowingly host spam infrastructure.
Reputation impact
Severe. SBL is a high-confidence list; most filtering systems treat it as a hard signal.
How to delist
Identify the SBL number from the lookup result, address the root cause (terminate the spam operation, secure the netblock, enforce abuse policies), and submit a removal request through the SBL Removal procedure linked from the lookup page.
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