Physician Assistant services be billed under E&M codes?

Can Physician Assistant use E&M codes, such as 99213, and bill under their own NPI #?

PA's

Yes, of course. E/M codes are in the PA's scope of practice.

Check with your commercial payers about whether or not they credential a PA, and read the sections in Codapedia about incident to and shared services. Also, search for articles on the word Physician Assistant.

You can also browse articles by tag or category by selecting that option on the left "Browse entries by tag" That might give you the most information, most easily.