Can I have multiple handsets on the same Cloud Telephony account?

Although you can have up to three (3) simultaneous connections to one extension; there are limitations to sharing extensions. 

For example: If one person is on the phone on one connected device, then you will not be able to make a call from the other connected device while it is in use.

We advise you to have one extension per physical device, unless both are used by one user.