We're often asked if an IP address can be used in an SSL certificate in place of a fully qualified domain name. The short answer is yes, but we don't recommend it. If your IP address changes your SSL certificate can become useless.
If you decide that you really need an IP in your cert there are specific stipulations, conditions, and limitations to consider.
Yes! You can add a SAN for an IP Address to any non-EV Multi-domain Certificate. The SANs must meet the same Requirements and Restriction mentioned above.
If you cannot prove your organization has been assigned the IP by placing a .txt file on your web server, there is a workaround, but it's not recommended as a first choice. The vetting team can attempt to call the Point of Contact (POC) listed on the WHOIS for your IP address to confirm you have permission to use the IP. Please understand that while the vetting team can attempt to place a call to the POC, there's no guarantee the POC will call them back.
To see the underlying WHOIS information for your IP you can use the following links that are approved for official IP contacts and assignments.
When using ARIN you don't need an account. Type your IP in the upper-right corner of the page in the SEARCH WhoisRWS box.
Please contact our support team if you have any additional problems or questions.