Blocklist Lookup

Don't miss the opportunity to reach subscribers' inboxes.


Return Path offers a free Blocklist Lookup tool that will tell you if your IP address is on an email blacklist. To check your IP address right now, fill out the form below.

What is blocklisting?

Return Path collects and provides a collection of email server IP addresses that engage in spam-like behavior and unsafe email practices, also known as the Return Path Blocklist (RPBL). This blocklist is widely used and based on data from Return Path’s robust data sources and cooperative industry partnerships. Mailbox providers, security companies, and spam filtering agencies use this list of IPs to make important decisions about blacklisting and spam filtering.

The Return Path Blocklist identifies spam-like sending practices and classifies emails based on specific criteria. These calculations are centered around sender behavior and sender content such as threatening attachments, spam trap hits, and authentication failures. An IP is listed when our system detects messages containing these indicators from that IP. This blocklist is used by mailbox providers, security vendors, and filtering agencies as a contributing factort in their filtering algorithms and policies.

If you find yourself on a blocklist, you may request temporary removal. Fixing the root problem that generated your blocklisting takes time and effort, but our deliverability experts will make the process simple. Contact us for more information.

Featured Resources


2019 Hidden Metrics of Email Deliverability

Learn More


The State of Email Engagement

Learn More


2018 Deliverability Benchmark

Learn More

We Know Email

We’re the experts in deliverability and driving results for your email marketing.

Request a Demo