What is the best way to deal with being blocklisted by Spamhaus?
Matthew Whittaker
Co-founder & CTO, Suped
Published 29 May 2025
Updated 16 Aug 2025
8 min read
Getting blocklisted by Spamhaus can feel like a sudden stop to your email operations. One moment your emails are flowing, the next they are bouncing back with messages indicating you're on a blacklist (or blocklist). It's a common and frustrating experience for many senders. However, reacting impulsively, such as immediately changing your IP address, often doesn't solve the underlying problem and can even make things worse in the long run. My goal here is to guide you through the most effective ways to address a Spamhaus listing, focusing on sustainable solutions that protect your sending reputation.
A Spamhaus listing isn't just a nuisance, it's a clear signal that something about your email sending practices, or the infrastructure you use, has triggered their sophisticated anti-spam mechanisms. Ignoring these signals or applying quick fixes without addressing the root cause will likely lead to repeated listings. This can severely damage your long-term email deliverability and sender reputation.
The best approach involves a systematic process of identifying the issue, resolving it, requesting delisting, and implementing measures to prevent future occurrences. It requires understanding what triggered the blocklist entry and being proactive in your email management. Let's delve into the steps you should take.
Before you can fix the problem, you need to understand precisely what caused the listing. Spamhaus operates several distinct blocklists, each targeting different types of problematic activity. For instance, the Spamhaus Blocklist (SBL) lists IP addresses actively engaged in sending spam, while the Don't Route Or Peer (DROP) list contains networks hijacked by spammers. Knowing which specific blocklist your IP or domain is on, and the reason provided for the listing, is crucial. You can use their IP & Domain Reputation Checker to get this information.
A common cause for being blocklisted is the presence of malware on your sending servers or compromised accounts sending spam without your knowledge. Another frequent issue is poor list hygiene, leading to high bounce rates or hitting spam traps, which are email addresses used to identify spammers. Understanding what causes Spamhaus blacklisting is the first critical step.
The information provided by Spamhaus about your listing often includes clues about the underlying problem. It might indicate if your IP is associated with a botnet, if your domain is sending unsolicited bulk email, or if it's listed due to policy violations. This initial diagnosis is paramount for crafting an effective resolution strategy.
I often see confusion between different types of blocklists. For example, Spamhaus CSS listing relates specifically to IP addresses observed sending low-reputation or suspicious mail to consumer ISPs, often affecting Outlook and Hotmail delivery. Each type of listing requires a slightly different approach, so precision in identifying the listing type is key.
Addressing the root cause
Delisting from Spamhaus without addressing the root cause is a temporary fix at best. Your IP or domain will likely be re-listed very quickly. This is why fixing the underlying problem is the most crucial step. If your server is compromised and sending spam, you need to identify and remove the malicious software. If your email list contains old, unengaged, or rented addresses, you need to clean it thoroughly. For issues related to malware emitting spam, a comprehensive server scan is essential.
Immediate actions
Pause sending: Immediately halt all email sending from the affected IP address or domain to prevent further damage.
Investigate: Analyze your server logs, email system, and network for suspicious activity, unusual traffic, or signs of compromise.
Secure: Implement security patches, change passwords, and close any open relays or vulnerabilities.
Clean lists: If the issue is related to email marketing, cleanse your email lists of invalid or unengaged subscribers. Consider implementing double opt-in for new sign-ups.
For server compromises, you might need to run comprehensive anti-malware scans and review your system's configuration. Here’s an example command for a basic malware scan using common Linux tools, although dedicated security software is highly recommended for thoroughness.
Once you've identified and fixed the root cause, you'll be in a much stronger position to request delisting, as you can confidently explain what was wrong and how you've resolved it. This commitment to fixing the underlying issues is what Spamhaus looks for.
The delisting process
The delisting process itself varies slightly depending on the specific Spamhaus blocklist you're on, and whether you manage your own IP space or use a shared service. For IPs, especially if they are dynamic or part of a larger network, Spamhaus often requires the Internet Service Provider (ISP) or hosting provider to initiate the delisting. This is because ISPs are responsible for managing their IP allocations and ensuring their network isn't abused. Contacting your ISP's abuse team is a common first step for IP-based listings. They should have procedures in place for working with blocklists like Spamhaus.
For domain-based listings (DBL) or if you own your IP space and have direct control over your server, you can often initiate the delisting directly through the Spamhaus website. You'll need to provide details about the listing, what caused it, and the steps you've taken to remediate the issue. Transparency and a clear explanation of your actions increase the likelihood of a successful delisting. Remember, contacting Spamhaus directly is key if you have direct control.
ISP/Hosting Provider handled delisting
Responsibility: The ISP or hosting provider submits the delisting request.
When to use: If you are on a shared IP, dynamic IP, or an IP allocated by your provider, like the Spamhaus PBL.
Communication: You must clearly communicate the issue and resolution to your ISP/provider.
Direct delisting (for IP/domain owners)
Responsibility: You submit the delisting request yourself via the Spamhaus website.
When to use: If you own and manage your own IP addresses or your domain is listed on the Spamhaus DBL.
Evidence: Be prepared to explain the cause and your resolution actions clearly.
After submitting a delisting request, monitor your status. Spamhaus typically processes requests quickly once the root cause is confirmed to be resolved. Continued vigilance is necessary to ensure you stay off the blocklist and that your email deliverability is restored. This often involves continuous blocklist monitoring.
Preventing future listings
The ultimate goal isn't just to get off a Spamhaus blocklist (or blacklist), but to avoid being listed again. This requires a proactive approach to email management and security. One of the most important aspects is robust email authentication. Implementing SPF, DKIM, and DMARC helps mail receivers verify that your emails are legitimate and haven't been tampered with. This significantly boosts your sender reputation.
Beyond authentication, maintaining a clean and engaged subscriber list is paramount, especially for email marketing. Regularly cleaning your list to remove inactive or invalid addresses, using double opt-in for new sign-ups, and segmenting your audience to send relevant content can drastically reduce complaint rates and the likelihood of hitting spam traps. Ignoring list hygiene is a leading cause for repeat blocklistings.
Furthermore, continuous DMARC monitoring provides invaluable insights into your email ecosystem, allowing you to quickly detect and mitigate unauthorized sending from your domain. This proactive vigilance is critical for maintaining long-term email health and avoiding future blocklists, including Spamhaus CSS listings.
Prevention Strategy
Why it Matters
Key Actions
Email Authentication (SPF, DKIM, DMARC)
Verifies sender identity and prevents spoofing, improving trust with email providers like Google and Yahoo.
Set up a DMARC record and gradually enforce policies. Ensure proper SPF and DKIM configuration.
List Hygiene and Consent
Reduces bounces and spam complaints by ensuring you send to valid, engaged recipients.
Use double opt-in, regularly clean inactive subscribers, and remove hard bounces.
Security Audits
Prevents compromises that could lead to your systems being used to send spam.
Regularly scan servers for malware, update software, and secure email accounts.
Monitoring and Reputation Management
Allows for early detection of issues before they escalate into blocklistings.
Always address the root cause of the listing first, such as compromised servers or poor list hygiene.
Communicate clearly and transparently with Spamhaus about the steps taken to resolve the issue.
Implement email authentication (SPF, DKIM, DMARC) to build a strong sender reputation.
Common pitfalls
Attempting to simply change IP addresses without fixing the underlying problem, leading to repeated listings.
Ignoring bounce messages and deliverability reports, missing early warning signs.
Sending to old, unengaged, or rented email lists, which increases spam complaint rates and hits spam traps.
Expert tips
Monitor your sending infrastructure continuously for any signs of compromise or unusual activity.
Educate your team on email sending best practices to avoid common pitfalls.
Engage with the abuse desks of your ISPs and hosting providers to ensure they are aware of and support your delisting efforts.
Marketer view
Marketer from Email Geeks says changing your IP address without fixing the underlying issues is a temporary measure that won't resolve the problem long-term.
2022-07-12 - Email Geeks
Expert view
Expert from Email Geeks says that trying to find a quick fix for a Spamhaus listing, such as getting a new IP, is counterproductive and won't lead to sustainable email deliverability.
2022-07-12 - Email Geeks
Moving forward
Dealing with a Spamhaus blocklist (or blacklist) can be daunting, but it’s a manageable situation with the right approach. The key takeaway is that delisting is a process that begins with thoroughly understanding and fixing the root cause of the listing, not just seeking a quick removal. Whether it’s a compromised server, poor sending practices, or a vulnerable email system, identifying and addressing the core issue is non-negotiable for long-term email deliverability.
Once the underlying problem is resolved, initiating the delisting request through the appropriate channels – either directly with Spamhaus or via your ISP – becomes a much smoother process. Spamhaus appreciates transparency and evidence of remediation.
Ultimately, the best way to deal with being blocklisted by Spamhaus is to prevent it from happening again. This involves implementing robust email authentication, maintaining excellent list hygiene, and continuously monitoring your email infrastructure and sender reputation. By adopting these best practices, you can ensure your legitimate emails reach their intended recipients and avoid future disruptions.
Spamhaus
0Spam
Cisco
NoSolicitado
URIBL
abuse.ro
ALPHANET
Anonmails
Ascams
BLOCKEDSERVERS
Calivent Networks
EFnet
JustSpam
Kempt.net
NordSpam
RV-SOFT Technology
Scientific Spam
Spamikaze
SpamRATS
SPFBL
Suomispam
System 5 Hosting
Team Cymru
Validity
www.blocklist.de Fail2Ban-Reporting Service
ZapBL
2stepback.dk
Fayntic Services
ORB UK
technoirc.org
TechTheft
Google and 
Yahoo.
