A list of IP addresses that are known to send unsolicited or unwanted emails.
A deny list (some services use the term, "blacklist" or "blocklist") is a list of IP addresses that have been detected sending unsolicited and unwanted emails. Inbox service providers (like Gmail, Microsoft, Yahoo, and AOL) and enterprises use deny lists to identify and filter illegitimate mail streams. Specific sending domains, in addition to sending IPs, can also be added to a deny list.
All major ISPs use some form of deny listing service to protect their customers from malicious emails, although the deliverability impact can vary depending on the service that lists the IP. If you find that your IP address is on the deny list of one the many legitimate services, then submit a delisting request.
SendGrid keeps a close eye on our IP's, and we try as quickly as possible to resolve any issues with deny lists. However, getting your IP off the deny list often requires the user sending the mail to contact the ISP.
We ask that our dedicated IP plan users make the initial delisting request if they discover their SendGrid IP on a deny list. SendGrid is happy to step in and assist with these delisting requests if the listing service requires the IP administrator to take action, or if the delisting form is too complicated.
If a sending domain (and not the IP address) is blocked, that domain's controller is responsible for handling the delisting request.
Here are 2 aggregation websites that anyone can use to check on the status of their IP:
Below are links to the delisting forms used by the more popular external deny listing services:
If you are sending mail using these guidelines and still have problems delivering email to those email providers, you can contact the ISP support by the following URL:
If a listing service ever asks you pay a fee for a delisting request, or if they say that they do not accept delisting requests, then you should not waste your time or money trying to get your domain/IP delisted because these services are rarely, if ever, used by ISPs.
Looking for customized expert advice to improve your email program? Our team of email experts can help you create a plan to ensure you're optimizing your email delivery and engagement, and avoiding future issues like deny lists. Learn more on our Expert Services page.