An email blacklist, more accurately called a blocklist, is a public list of IP addresses or domains that mailbox providers use to reject or filter mail. To get delisted, check which list you are on, find and fix the cause, then follow that list's removal process. Requesting removal before fixing the cause usually fails.
How do you know you are blocklisted?
Signs include sudden bounces with messages that mention a blocklist, a drop in delivery to certain providers or a platform notice. Run your sending IP and domain through a multi-list lookup such as the one at MXToolbox. Read bounce messages closely, because they often name the list and give a removal link.
What are common causes?
- Mailing a purchased or scraped list, including spam traps.
- A compromised account or website form that sent spam.
- High complaint rates after a campaign.
- A shared IP where another customer misbehaved.
- A new IP without a warm-up.
How do you get removed?
- Identify the list. Not all lists matter equally: Spamhaus listings are widely used by providers, while minor lists have little effect.
- Find the cause. Check for compromised credentials, review recent campaigns and the list source.
- Fix the problem. Remove bad addresses, secure accounts and correct authentication. See the authentication guide.
- Follow the list's own delisting process, which may be a web form, and explain what you changed.
- Wait. Some listings expire on their own after a period without bad traffic.
- Resume sending slowly, using warm-up principles.
What if you are on a shared IP?
If your platform's IP is listed, contact their support. They manage the pool and the delisting. Persistent listings may be a reason to move to a better provider or a dedicated IP. See dedicated vs shared IP.
Which blocklists matter most?
Blocklists differ a lot in reach. Spamhaus lists are used by many mailbox providers and receiving servers, so a listing there can affect delivery widely. Smaller or regional lists may affect only the servers that subscribe to them. Always read the listing reason and the operator's removal policy before you act, because some lists want evidence of a fix and others simply expire entries.
How do you avoid it next time?
Keep complaint and bounce rates low, clean your list with list hygiene and monitor with Postmaster Tools and a regular deliverability test. For a complete picture see email deliverability explained.
Frequently asked questions
Can I pay to be removed from a blocklist?
Legitimate blocklists do not sell removal. Be careful with any service that charges to delist you.
How long does delisting take?
Some are processed within a day, others take longer or expire automatically. It depends on the list.
Will delisting fix my spam placement?
Only if the listing was the cause. Reputation, authentication and content still matter.
Does being on one small blocklist matter?
Usually little. Large lists used by many providers matter far more.