# What to do if your domain is blacklisted

> How to check whether your domain is on a blacklist, what to do if it is, and how to prevent it.

Source: https://www.kualo.com/knowledgebase/senders-deliverability/what-to-do-if-your-domain-is-blacklisted
Updated: 2026-06-10

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A blacklist is a list of IP addresses or domains that receiving mail servers treat as untrustworthy. They're run by anti-spam groups, and most listings come from sending unsolicited bulk email to people who never asked for it. Some blacklists carry far more weight than others, so it's worth keeping yours clean.

## Check whether you're listed

Look your domain up on one of these blacklist-check services:

- http://multirbl.valli.org/lookup/
- https://mxtoolbox.com/blacklists.aspx
- http://www.blacklistalert.org/
- http://www.dnsbl.info/dnsbl-list.php

## If you're listed

The fastest route to removal is understanding what caused the listing in the first place, so the problem doesn't simply recur. [Open a support ticket](/knowledgebase/getting-started/how-to-create-a-support-ticket-in-mykualo) and our team can help you work out the cause and the path to delisting.

## Prevent it happening again

The single best preventative measure is to keep your list clean and consented. Send a reconfirmation email to your recipients every few months - how often depends on your sending frequency and list size - so you're only ever mailing people who still want to hear from you.

For the wider picture, see **[Email deliverability basics](/knowledgebase/senders-deliverability/email-deliverability-basics)** and **[Protect your sender reputation](/knowledgebase/senders-deliverability/protect-your-sender-reputation)**.

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_Source: Kualo Knowledgebase — https://www.kualo.com/knowledgebase/senders-deliverability/what-to-do-if-your-domain-is-blacklisted · © Kualo Ltd._