Opt out of requiring country code for phone number column

One of my colleagues has a form that he wants to request the client’s phone number on, but it’s cumbersome to request the country code as well. All of our clients are in one state within the U.S., so there really isn’t a need for the country code. It would be nice to be able to opt out of including that in the form. We’ve tried to use Number/Text columns instead, but those don’t work as well for a phone number.