Email Blacklist Check: How to Find and Remove Your IP/Domain

8 min read

Email Blacklist — How to Check If You're on One and Get Removed

Your emails stopped working overnight. Recipients aren't getting your messages. Bounce-back errors mention "blocked by policy." You're probably on an email blacklist.

Email blacklists (also called DNSBLs or RBLs) are databases of IP addresses and domains known for sending spam. When your IP or domain gets listed, major email providers automatically block or junk your emails.

Here's how to check if you're blacklisted and exactly how to get removed.

What Email Blacklists Actually Are

Blacklists are maintained by anti-spam organizations. They monitor spam traps, collect abuse reports, and track suspicious sending behavior.

When an IP address or domain triggers their criteria, it gets added to the blacklist. Email providers (Gmail, Outlook, Yahoo) check these lists before accepting mail. If you're listed, your email gets rejected or sent to spam.

Major blacklists that matter:

Being on Spamhaus kills your deliverability. Being on smaller lists might only affect specific providers or corporate networks.

Why You Got Blacklisted

Spam traps. These are fake email addresses created specifically to catch spammers. They're never used by real people. If you're emailing them, you bought a list or scraped addresses.

High complaint rates. Recipients mark your emails as spam. If enough people complain, blacklist operators take notice.

Sending to invalid addresses. High bounce rates signal you're not maintaining your list properly. Spammers don't care about bounces — you shouldn't act like one.

Compromised server. Your website or email server got hacked. Attackers use it to send spam without your knowledge.

Shared IP contamination. You're on a shared server. Someone else on the same IP sent spam. You get caught in the blast radius.

Bought email lists. The fastest way to get blacklisted. Purchased lists always include spam traps.

Poor list hygiene. Sending to people who never signed up, haven't engaged in months, or hit unsubscribe.

How to Check If You're Blacklisted

Check Your IP Address

First, find your sending IP address.

If you send from your own server: 

curl ifconfig.me

If you use an email service:

Check your email headers. Look for "Received" lines. The IP in the first "Received" line is usually your sending IP.

Or check your service provider's dashboard. SendGrid, Mailgun, AWS SES all show your sending IPs.

Check Major Blacklists Manually

Spamhaus: 1. Go to https://www.spamhaus.org/lookup/ 2. Enter your IP address or domain 3. If listed, you'll see which list (SBL, XBL, PBL) and why

Barracuda: 1. Go to https://barracudacentral.org/lookups 2. Enter your IP 3. Check reputation score and listing status

SORBS: 1. Go to http://www.sorbs.net/lookup.shtml 2. Enter your IP 3. Shows all SORBS lists you're on

MXToolbox (checks 100+ lists at once): 1. Go to https://mxtoolbox.com/blacklists.aspx 2. Enter your IP or domain 3. Get results from major blacklists

Or use checkyouremail.online - checks multiple blacklists automatically and shows you which ones matter most.

Test now → checkyouremail.online (free, no signup)

Check Your Domain Reputation

Blacklists primarily focus on IPs, but some also list domains.

Check domain-based lists:

Use the same lookup tools but enter your domain instead of IP.

How to Get Removed from Blacklists

Step 1: Stop the Problem Immediately

Don't request delisting while you're still sending spam. Blacklist operators will ignore you or relist you immediately.

Fix the root cause:

Wait 24-48 hours after stopping the problem before requesting removal.

Step 2: Request Removal from Spamhaus

Spamhaus is the most important. Focus here first.

1. Go to https://www.spamhaus.org/lookup/ 2. Enter your IP address 3. If listed, click the removal link on the results page 4. Fill out the removal request form 5. Explain what caused the listing 6. Describe what you fixed 7. Submit the request

What Spamhaus wants to hear:

Don't say:

Spamhaus typically responds within 24 hours. If they approve, delisting is instant. If denied, they'll explain why.

Step 3: Barracuda Removal

Barracuda often delists automatically once you fix the problem.

Manual removal:

1. Go to https://barracudacentral.org/account/register 2. Register an account 3. Go to https://barracudacentral.org/rbl/removal-request 4. Submit removal request with your IP 5. Explain the issue and resolution

Barracuda uses reputation scores. If your score improves, you'll be automatically delisted within 24-48 hours.

Step 4: SORBS Removal

SORBS is notoriously difficult. They're aggressive about listing and slow to delist.

Some SORBS lists automatically expire after 1-2 weeks if the problem stops. Others require payment ($50 USD) for "immediate" removal.

Free removal option:

Wait. Most SORBS listings automatically age out. If you're not actively spamming, you'll be delisted eventually.

Paid removal:

1. Go to http://www.sorbs.net/delisting.shtml 2. Follow their paid removal process 3. Provide documentation of fixes

Consider whether paying is worth it. Many email admins don't use SORBS because of its aggressive policies.

Step 5: SpamCop Removal

SpamCop listings automatically expire after 24-48 hours if no new spam is reported from your IP.

You can't request manual removal. Just stop spamming and wait.

Monitor at https://www.spamcop.net/bl.shtml

Step 6: Check Other Lists

Use MXToolbox or checkyouremail.online to check if you're on other lists.

Most smaller blacklists provide removal forms on their websites. Google "[blacklist name] removal request" to find the form.

How Long Does Delisting Take?

After delisting, test your deliverability immediately at checkyouremail.online.

What If You Keep Getting Relisted?

You're getting delisted but end up back on the blacklist within days or weeks. This means you haven't actually fixed the underlying problem.

Common causes:

Ongoing server compromise. Scan for malware: 

sudo clamscan -r /var/www/

Check for unauthorized email scripts in your web directories.

Shared IP pollution. If you're on shared hosting, request a dedicated IP or switch providers.

Poor list hygiene. You're still sending to unengaged recipients. Clean your list aggressively:

Volume spikes. Sudden increases in sending volume trigger suspicion. Gradually increase over 2-3 weeks.

Content issues. Your email content still looks like spam. Use checkyouremail.online to analyze what's triggering filters.

Preventing Future Blacklisting

Monitor Blacklists Proactively

Don't wait until emails stop working to check.

Set up monitoring:

checkyouremail.online can become part of your regular testing routine.

Maintain Clean Lists

Remove hard bounces immediately. Don't keep emailing addresses that don't exist.

Remove soft bounces after 3-5 attempts. Full inboxes and temporary failures eventually become permanent.

Purge non-engagers. If someone hasn't opened an email in 60 days, stop sending to them.

Honor unsubscribes instantly. Continuing to email after unsubscribe guarantees spam complaints.

Implement Proper Authentication

SPF, DKIM, and DMARC don't directly prevent blacklisting, but they prove you're a legitimate sender.

Minimum required:

Test your authentication → checkyouremail.online

Use Dedicated IP (If Sending High Volume)

If you send 100,000+ emails per month, get a dedicated IP address.

Shared IPs mean shared reputation. One bad sender on your shared IP affects everyone.

Dedicated IP benefits:

Downside:

Monitor Feedback Loops

Major ISPs offer feedback loops — they notify you when recipients mark your email as spam.

Set up FBLs with:

When you get spam complaints, investigate immediately. One or two is normal. Hundreds means serious problems.

Segment and Personalize

Generic mass emails trigger more spam complaints than personalized ones.

Better approach:

Special Case: Dedicated IP Was Blacklisted Before You Got It

You got a new dedicated IP for email sending. Checked blacklists. Already listed.

This happens. Previous owner of the IP spammed. You inherited their bad reputation.

Options:

Request a different IP. Ask your provider for a clean IP. Reputable providers should give you one with no blacklist history.

Get the IP delisted before using it. Request removal from all lists before sending a single email.

Wait it out. Most blacklist entries automatically expire. Wait 30-90 days without using the IP.

Contact your provider. They should handle this. It's their responsibility to provide clean IPs.

Don't start sending from a blacklisted IP. You'll immediately get relisted and tank your sender reputation.

Tools for Blacklist Monitoring

MXToolbox Monitoring ($])

Paid service that checks 100+ blacklists and alerts you immediately upon listing.

Blacklist Alarm ($)

Similar to MXToolbox. Monitors multiple IPs and domains.

checkyouremail.online (Free)

Checks major blacklists as part of comprehensive deliverability testing. No signup required.

Google Postmaster Tools (Free)

Shows your reputation at Gmail specifically. Not a blacklist checker but useful for Gmail deliverability.

What to Do While You're Blacklisted

Option 1: Use a different IP

If you have access to another IP address, send from that while waiting for delisting.

Option 2: Use a third-party service temporarily

Services like SendGrid, Mailgun, or AWS SES have established IP pools with good reputation. Use them while you fix your own infrastructure.

Option 3: Send only to critical recipients

Drastically reduce volume. Send only to people who absolutely need to receive your emails (customers, not prospects).

Don't:

Blacklist operators track this behavior. You'll make things worse.

Blacklist Myths Debunked

Myth: "I can pay to get delisted faster"

Most legitimate blacklists don't accept payment for removal. SORBS is an exception. Anyone asking for payment to remove you from Spamhaus or SpamCop is scamming you.

Myth: "Using a VPN changes my sending IP"

VPNs affect your browsing IP, not your email sending IP. Your emails send from your mail server's IP, which doesn't change based on your VPN.

Myth: "Small blacklists don't matter"

True for most. But if your recipients use enterprise email security systems, even obscure blacklists can affect delivery to those companies.

Myth: "I can just get a new domain"

New domains have zero reputation. ISPs don't trust them. You'll have different deliverability problems. Fix your current domain instead.

Final Checklist

Being blacklisted isn't permanent. Fix the cause, request removal, and improve your practices. Your deliverability will recover.

Run a free deliverability check right now at checkyouremail.online — no signup, results in 30 seconds.