Yes it is now possible to host multiple SSLs on a Single IP with help of SNI.
What is SNI?
Server Name Indication (SNI) is designed to solve this problem. SNI is an extension for the TLS protocol (formerly known as the SSL protocol), which is used in HTTPS. It’s included in the TLS/SSL handshake process in order to ensure that client devices are able to see the correct SSL certificate for the website they are trying to reach. The extension makes it possible to specify the hostname, or domain name, of the website during the TLS handshake, instead of when the HTTP connection opens after the handshake.
More simply put, SNI makes it possible for a user device to open a secure connection with https://www.example.com even if that website is hosted in the same place (same IP address) as https://www.something.com, https://www.another-website.com, and https://www.example.io.
For more read https://www.cloudflare.com/learning/ssl/what-is-sni/
Now here is how to configure SSL on single IP.
Open IIS
Select your Websites under Sites in Left Panel.
Select Bindings under Actions Tab in Right Panel.
Click Add Button and choose option as follows
Under IP address you can choose Public IP or choose All unassigned.
Check Require Server Name Indication.
At least one other site is using the same HTTPS binding and the binding is configured with a different certificate. Are you sure that you want to reuse this HTTPS binding and reassign the other site or sites to use the new certificate?
If you don’t select this option following error might appear and when server restarts or IIS restart some application might not not have SSL.
