Discovering your email domain on a blacklist can be devastating for deliverability. When major blacklists flag your domain, your emails may be blocked entirely, causing lost revenue, damaged reputation, and frustrated customers. This step-by-step guide shows you exactly how to identify which blacklists have flagged you, fix the root cause, submit delisting requests, and prevent future listings.

Why Blacklists Matter for Email Deliverability

The Impact of Blacklisting

• Complete email blocking: Major ISPs and email providers reject messages from blacklisted domains
• Damaged sender reputation: Blacklist status signals to ISPs that your domain is untrustworthy
• Lost revenue: Emails that never reach inboxes mean zero engagement and zero conversions
• Long-term consequences: Even after delisting, some ISPs may continue blocking based on historical data

Common Blacklist Types

• IP-based blacklists: Flag specific sending IP addresses
• Domain-based blacklists: Flag entire domains or subdomains
• RBL (Real-time Blackhole Lists): Continuously updated lists like Spamhaus
• Private blacklists: Maintained by individual ISPs like Microsoft, Google, Yahoo

Step 1: Identify the Blacklist(s) & Cause

Use Lookup Tools

Check your domain and IP address on multiple blacklist lookup services to get a comprehensive view of your status:

Recommended Tools:

• MXToolbox Blacklist Check: Free tool that checks your domain against 100+ blacklists
• DNS Checker: Comprehensive blacklist monitoring with detailed reports
• Spamhaus: Check against the most respected RBL in the industry
• MultiRBL: Aggregates results from multiple blacklist databases

How to Check:

1. Enter your domain name (e.g., example.com)
2. Enter your sending IP address (if known)
3. Review the results to see which blacklists have flagged you
4. Note the severity level (some blacklists are more impactful than others)

Diagnose the Problem

Once you know which blacklists have flagged you, identify the root cause. Common reasons include:

High Spam Complaint Rates

• Recipients marking your emails as spam
• Complaint rates above 0.1% can trigger blacklisting
• Check your email service provider's complaint reports

Sending to Spam Traps

• Old, unused email addresses that ISPs monitor
• Purchased email lists often contain spam traps
• Honeypot addresses designed to catch bad senders

Compromised Accounts

• Unauthorized access to your email server
• Malware sending spam from your domain
• Phishing attacks using your domain name

Poor Email Authentication

• Missing or incorrect SPF records
• DKIM misconfiguration
• DMARC policy failures
• Authentication failures signal untrustworthy sending

High Bounce Rates

• Sending to invalid email addresses
• Poor list hygiene practices
• Bounce rates above 5% can trigger blacklisting

Step 2: Fix the Root Cause

Before requesting delisting, you must fix the underlying problem. Blacklist operators will reject requests if the root cause isn't addressed.

Email Authentication Setup

Proper authentication proves you're a legitimate sender and prevents domain spoofing.

SPF (Sender Policy Framework)

• Create or update your SPF record in DNS
• Include all authorized sending servers
• Use ~all or -all to specify handling of unauthorized senders
• Test your SPF record using MailMoxie's DNS Record Checker

DKIM (DomainKeys Identified Mail)

• Generate DKIM keys for your domain
• Add the public key to your DNS records
• Configure your email server to sign outgoing messages
• Verify signatures are being applied correctly

DMARC (Domain-based Message Authentication, Reporting & Conformance)

• Set up DMARC policy (start with p=none for monitoring)
• Gradually move to p=quarantine then p=reject
• Monitor DMARC reports to identify authentication failures
• Use MailMoxie's DNS Record Checker to verify your DMARC setup

Email List Hygiene

Clean, engaged lists reduce spam complaints and bounce rates.

Remove Inactive Users

• Identify subscribers who haven't engaged in 6+ months
• Send re-engagement campaigns before removing
• Remove unengaged subscribers to improve list quality

Remove Invalid Addresses

• Process bounces immediately
• Remove hard bounces from your list
• Monitor soft bounces and remove after multiple failures
• Use email validation services to verify addresses

Stop Using Purchased Lists

• Purchased lists contain spam traps and invalid addresses
• They violate anti-spam laws (CAN-SPAM, GDPR)
• Build your list organically through opt-ins
• Focus on quality over quantity

Security Measures

Protect your domain from compromise and spoofing.

Scan for Malware

• Run antivirus scans on your email server
• Check for unauthorized access attempts
• Review server logs for suspicious activity
• Update all software and security patches

Secure Your Server

• Use strong passwords and two-factor authentication
• Implement firewall rules to restrict access
• Monitor for unauthorized login attempts
• Keep all software updated

Prevent Domain Spoofing

• Set up SPF, DKIM, and DMARC records
• Use DMARC p=reject policy to block unauthorized senders
• Monitor DMARC reports for spoofing attempts
• Educate your team about phishing prevention

Stop Sending to Spam Traps

Spam traps are email addresses used by ISPs to identify bad senders.

Avoid Old Email Addresses

• Remove addresses that haven't engaged in years
• Don't send to addresses collected more than 2 years ago
• Use double opt-in to verify addresses are active

Identify Honeypot Addresses

• Honeypots are addresses that should never receive email
• If you're sending to honeypots, your list hygiene is poor
• Review your list sources and remove suspicious addresses

Best Practices

• Only send to subscribers who explicitly opted in
• Use confirmed opt-in (double opt-in) when possible
• Regularly clean your list of inactive subscribers
• Never purchase or rent email lists

Step 3: Submit Delisting Requests

Once you've fixed the root cause, submit delisting requests to each blacklist that has flagged you.

Find the Provider's Page

Each blacklist has its own delisting process. Here are links to major blacklists:

Major Blacklist Delisting Pages:

• Spamhaus: Blocklist Removal Center
• Microsoft: Smart Network Data Services
• Google Postmaster Tools: Postmaster Tools
• Barracuda: BarracudaCentral
• SpamCop: SpamCop Blocking List
• Surbl: Surbl Removal

Fill Out the Form

When submitting delisting requests, provide clear, detailed information:

Required Information:

• Domain or IP address: The exact address that was blacklisted
• Explanation of the problem: What went wrong (e.g., "compromised server," "poor list hygiene")
• Steps taken to fix it: Specific actions you've taken (e.g., "implemented SPF, DKIM, DMARC," "cleaned email list")
• Prevention measures: What you'll do to prevent future issues (e.g., "regular list cleaning," "monitoring authentication")
• Contact information: Valid email address for follow-up

Example Delisting Request:

Our domain example.com was blacklisted on [Date]. We identified the cause as a compromised email server that was sending spam. We have since:

1. Secured the server and removed malware
2. Implemented SPF, DKIM, and DMARC authentication
3. Cleaned our email list of invalid addresses
4. Set up monitoring to detect future issues

We request removal from the blacklist and commit to maintaining best practices going forward.

Be Patient

Delisting requests take time to process:

• Typical timeline: 24-48 hours for most blacklists
• Some blacklists: May take up to 7 days
• Automatic removal: Some blacklists remove domains automatically after a period of good behavior
• Follow up: If you haven't heard back after 48 hours, follow up politely

What to Expect:

• Some blacklists require proof of fixes (screenshots, DNS records)
• You may need to answer follow-up questions
• Some blacklists have automatic removal after 30 days of clean sending
• Rejection is possible if the root cause isn't fully addressed

Step 4: Monitor & Prevent Re-Listing

After delisting, maintain best practices to stay off blacklists permanently.

Check Reputation Regularly

Monitor your domain's reputation to catch issues early:

Monitoring Tools:

• MailMoxie DNS Health Check: Monitor your SPF, DKIM, and DMARC records
• Google Postmaster Tools: Track spam rates and reputation
• Microsoft SNDS: Monitor sender reputation with Microsoft
• MXToolbox: Regular blacklist checks
• Sender Score: Monitor your overall sender reputation

Key Metrics to Watch:

• Spam complaint rate: Keep below 0.1%
• Bounce rate: Keep below 5%
• Authentication pass rate: Should be 100%
• Blacklist status: Check weekly

Maintain Best Practices

Continue using strong authentication and good list management:

Ongoing Authentication

• Regularly verify SPF, DKIM, and DMARC records are working
• Monitor DMARC reports for authentication failures
• Update DNS records if you change email providers
• Use MailMoxie's DNS Record Checker to verify setup

List Management

• Remove inactive subscribers regularly (every 6 months)
• Process bounces immediately
• Use double opt-in for new subscribers
• Never purchase or rent email lists

Content Quality

• Avoid spam trigger words in subject lines and content
• Test emails with MailMoxie before sending
• Maintain a good text-to-image ratio
• Use clear, professional language

Security

• Keep email server software updated
• Monitor for unauthorized access
• Use strong passwords and 2FA
• Scan for malware regularly

Common Blacklist Removal Mistakes to Avoid

Mistake 1: Requesting Delisting Before Fixing the Problem

Blacklist operators will reject requests if the root cause isn't addressed. Always fix the problem first, then request delisting.

Mistake 2: Not Providing Enough Detail

Vague delisting requests are often rejected. Be specific about what went wrong, how you fixed it, and what you'll do to prevent it.

Mistake 3: Ignoring Multiple Blacklists

If you're on multiple blacklists, submit requests to all of them. Being on one major blacklist can still hurt deliverability.

Mistake 4: Not Monitoring After Delisting

After delisting, continue monitoring your reputation. Many domains get re-listed because they don't maintain best practices.

How MailMoxie Helps Prevent Blacklisting

MailMoxie's email testing and DNS monitoring tools help you avoid blacklisting in the first place:

DNS Health Monitoring

• Check your SPF, DKIM, and DMARC records
• Identify authentication misconfigurations
• Get alerts when records change or fail

Email Testing

• Test emails before sending to catch spam triggers
• Identify content issues that could lead to complaints
• Verify authentication is working correctly

Deliverability Analysis

• AI-powered analysis of 50+ spam triggers
• Actionable recommendations to improve deliverability
• Regular testing to maintain sender reputation

Conclusion

Getting removed from blacklists requires identifying the root cause, fixing it properly, submitting detailed delisting requests, and maintaining best practices going forward. The process takes time, but with the right approach, you can restore your domain's reputation and improve deliverability.

Start by checking your blacklist status, then systematically address each issue. Once you've fixed the problems, submit professional delisting requests and commit to ongoing monitoring and maintenance. With proper email authentication, clean lists, and good sending practices, you can stay off blacklists permanently.

Get Started

Ready to prevent blacklisting and improve your email deliverability? Use MailMoxie's free DNS Record Checker to verify your authentication setup, then test your emails before sending to catch issues early.

Need help removing your domain from a blacklist? Contact our support team for personalized assistance with delisting requests and making sure your domain stays off of the blacklists.