How to Check Your Email IP Reputation & Blacklists Online
Read more to find out how to check your email IP reputation online and what to do if you've been blacklisted.
Blocklist
Also known as: Blacklist
A blocklist is a list of IP addresses or domains that are known for sending bad or unwanted email. If you are on a blocklist, inbox providers often block or filter your messages before anyone can see them.
Blocklists act like a do not let in list for email. They are kept by security and spam filtering services that track who sends risky traffic. If your sending IP address or domain shows spam like behavior, it can be added. Once you are on a blocklist, many inbox providers stop your messages before they arrive.
Blocklists matter because a single listing can drop your deliverability from healthy to almost zero overnight. Your marketing emails will not reach customers, and important transactional emails like receipts or password resets may bounce. Email providers and inbox filters check blocklists in the background when they receive mail. If they see your IP address or domain on a list, they often reject the message or put it in a low trust bucket.
You avoid blocklists by keeping your list clean and sending only to people who clearly asked for your email. Remove hard bounces and long term inactive contacts, and never buy lists. Watch complaint rates and sudden volume spikes, since both are common triggers for listings. If you do get listed, fix the root cause first, then follow the blocklist removal steps with a clear, honest explanation.
Related Terms
Blacklist(Blocklist)
An email blacklist is a list of IP addresses or domains that inbox providers treat as unsafe. If you are on one, your emails are more likely to land in spam or get blocked before they arrive.
Learn more →Whitelist(Allowlist)
An email whitelist is a list of trusted senders or domains that people or email systems approve so their messages go to the inbox instead of spam. It is the opposite of a blocklist.
Learn more →List(Audience)
Your email list is the group of people who have asked to hear from you by email. It is an audience you own and can contact any time without relying on ads or social platforms.
Learn more →Seed List(Seed Addresses)
A seed list is a small group of test email addresses you add to campaigns so you can see if messages land in the inbox, spam, or other folders before you send to your full list.
Learn more →Related Articles About Blocklist
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