IP Blacklists

Note: For Gmail and Outlook Mailboxes, the IPs will get delisted on their own.

Here are some steps you can take to Improve your IP Reputation and Avoid Blacklists

1. Check Blacklists:
   Use tools like MXToolbox or MultiRBL to identify which blacklists your IPs are listed on and determine the cause.

2. Contact Your ESP:
   Inform your email service provider that their shared IPs are blacklisted. They can handle delisting requests.

3. Request Delisting: Visit the blacklist provider's website to submit a delist request. Ensure you’ve addressed any issues causing the blacklist.

4. Use Dedicated IPs: Consider switching to dedicated IPs for more control over your reputation.

5. Improve Email Practices: Follow best practices—send to verified addresses, use double opt-ins, and monitor bounce rates to avoid blacklists.

6. Warm Up New IPs: Gradually increase sending volumes when using new or recently blacklisted IPs to build a good reputation.

7. Enhance Email Authentication: Ensure SPF, DKIM, and DMARC are correctly configured to authenticate your emails.

8. Fix rDNS: Make sure reverse DNS records match your domain to prevent spam flags.

9. Monitor Sending Behavior: Maintain good sending habits—keep bounce rates low and avoid sending to outdated contacts.
   

If you seem to have a good IP reputation, but emails are still landing in spam:
Improve your email copy

Is it worth getting these IP's unblocked?

If these are shared IPs, it’s worth evaluating the impact on your email campaigns. Your ESP may already be handling the issue, but if you see emails landing in spam due to blacklisting, consider pursuing delisting or switching to dedicated IPs for better control.

This way, you can safeguard your email reputation and ensure consistent deliverability—especially important when managing large volumes like the 150,000 emails per month you plan to send. Ultimately, reaching out to your ESP for guidance and possibly moving to a dedicated IP will offer you more stability and peace of mind.

Not all blacklists are equally impactful. Major ones like Spamhaus can severely affect email deliverability, while smaller ones (e.g., SORBS, UCEPROTECT) may not. Large providers often use major blacklists, while smaller ones rely on local lists.

If a service asks for payment or denies delist requests, it’s likely irrelevant to major mailbox providers.