How to Check If Your IP Is in the Spamhaus Block List

Suryanarayan Pal
BySuryanarayan Pal

6 mins read

The spam email volume is increasing day and accounted for 45.37% of all email traffic in 2021. To reduce the magnitude of this issue, Spamhaus Block List (SBL) identifies and blacklists IPs that indulge in spam, spoofing and phishing attacks and other malicious activity. The major email clients will Gmail will not accept your emails if your IP gets blacklisted in SBL.

So do you need to fear it? Well, no, if you aren’t a spammer.

But sometimes, even genuine email marketers’ IPs might end up in blocklists. So it’s a good idea to check if you’re currently in SBL and how to prevent such future occurrences. Let’s discuss the factors that can land your IP in SBL and 5 ways to avoid it.

  • What is a Spamhaus Block List?

  • How does the Spamhaus Block List work?

  • How to check if your IP address is listed in Spamhaus Block List

  • How to not end up again on Spamhaus Block List

  • Takeaways

What is a Spamhaus Block List?

Spamhaus Block List is an authoritative source of information for finding spammers who indulge in phishing, spoofing, and spam attacks. The list has a collection of IPs spammers use to send spam emails. It finds spammers effectively, and its real-time threat protection protects over 3 billion email accounts.

Spamhaus tracks a wide range of spammers, including spam content hosting services, spam services, spam gangs, IPs caught by Spamhaus spam traps, etc.

For this reason, many email behemoths like Gmail and Apple Mail use SBL to find spammers’ IPs, and if yours ever gets listed in SBL, email clients will reject or mark your email as spam.

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How does the Spamhaus Block List work?

Spamhaus checks for spam-like activity and stores the IPs that indulge in any of the following activities.

  • Spam hosting: IP’s that host websites on which spammers have advertised or placed unsecure content.

  • Spam operations: IPs involved in the spam operations listed in the Spamhaus Register of Known Spam Operations (ROKSO). A few examples include Amoroso Corporation, AtomPark Software, Inc., and BadCow / mAiLIEN.

  • Spam services: Do you sell paid email lists, email scrapers, email appenders, or similar services? If so, then Spamhaus will block your IP and domain since it considers these services to be spam promoting.

  • Security threats: IP addresses that pose security threats to Spamhaus users, including phishing sites, ransomware, hacking attempts, etc.

So when Spamhaus considers so many factors to identify spam IPs, are you doubtful whether you've accidentally violated any rules and landed in SBL?

Well, leave guesswork aside, and let's learn how to know for sure if your IP is in the SBL.

Related guide: Everything You Need To Know About Email Security

How to check if your IP address is listed in Spamhaus Block List

Follow these steps to know if your IP is in SBL.

  1. Go to and enter your domain name or IP address.

Enter your IP address and click lookup

  1. If you see a Your IP has no issues message with a cute robot, you've nothing to worry about.

A message displaying your IP has no issues

  1. But if it says your IP is listed in the SBL, you’ll see a message like this.

A message displaying your IP has issues

Source: Rackaid

To resolve this issue ASAP, you need to find the underlying reason and resolve it. More often than not, the main reason is a security breach that puts users’ data at risk.

5 ways to avoid landing on Spamhaus Block List

Here are the best practices you can follow to not end up on the Spamhaus Block List.

1. Check for security compromises

Even the biggest companies like Facebook have faced data breaches in the past. So if you are a victim of a data breach that compromised your users’ data, you’ll be blocked by Spamhaus.

Similar to data breaches, unencrypted emails and spoofed and phishing emails also cause major security concerns for your users. Spoofing and phishing techniques rely on social engineering to trick users and gain access to sensitive data.

Want to know how to safeguard your users’ data from being compromised? Incorporate the following tips in your campaigns.

  • Conduct employee security training to train your employees not to be tricked by spammers and cause security breaches.

  • Install an SSL (or TLS) certificate for your website and email server.

  • Set up authentication protocols such as SPF, DKIM, and DMARC.

Related guide: Email Security Best Practices to Keep Your Business Safe Today

2. Don’t send excessive emails

An average email user receives more than 100 emails per day. So your users may not like you sending an additional two emails every day because that’ll clutter their inboxes even more. But if you’re currently doing it or plan to do it in the future, be ready to receive a lot of spam complaints on your IP, getting blocked by the ISPs and SBL.

Apart from that, you shouldn’t send email blasts with a new email because that’s what spammers do. So to communicate yourself as a legit sender, you’ve to do domain warmup by sending a few emails with your new IP and increasing the number gradually. You can use an email cadence to figure out the sending schedule and plan accordingly. Additionally, you can use Google Postmaster Tools to check your sending reputation and ensure that your emails are not being marked as spam.

3. Avoid paid email lists

Buying an email list is a cardinal sin for email marketers. It goes against email laws such as GDPR and CAN-SPAM act, and you may face legal consequences and have to pay a fine in the magnitude of millions. Imagine how you'll feel when someone sells your email and strangers start sending you irrelevant emails. Not very pleasant, right? You’ll mark them as a spam source resulting in a decline in their IP reputation.

So if you insist on buying an email list to "speed up" your campaign success, you'll receive lots of spam complaints from those users, and Spamhaus will notice and won't remove your IP / domain from their list.

Related guide: What Is an Email List and How Can You Build it From Scratch

4. Setup authentication systems

If you haven't already, set up DMARC, DKIM, and SPF records in your email system.

DKIM assures that your email wasn’t modified while transmission. DMARC helps to prevent spoofing and phishing attacks. Finally, the SPF helps you establish yourself as the truthful owner of the emails.

So as you can see, these records are trust factors that establish your credibility as a genuine sender, and the chances of your IP or domain ending up SBL becomes tiny.

Related guide: Understanding Email Authentication Protocols: SPF, DKIM, and DMARC

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5. Manage email list hygiene

Your email list should contain your true fans interested in receiving your emails. So don’t keep users on your list who request you to unsubscribe them. Failing to remove such users will decrease your engagement rates and increase your spam rates. So create a suppression list with ESPs like Mailmodo that categorizes inactive users and keep cleaning your email list periodically.


While most email marketers fear Spamhaus, you shouldn't be if your intentions aren’t bad. They aren’t trying to stop you from reaching your subscribers but want you to do it acceptably. Spamhaus has the influence to make or break your email deliverability rates depending on whether you comply with its guidelines.

Similar to Spamhaus, ISPs (Internet Service Providers) can also profoundly affect your email deliverability. Read our guide on ISPs to know why they’re important and how to be on their good side.

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