CPT codes are procedural codes, and HCPCS codes are for matierials, biologicals, injectables, and "temporary" procedure codes that Medicare allows which are slightly different from very similar CPT codes. Example: 36415, the code most widely used for venipuncture, is not allowed by Medicare because 36415 also allows finger sticks and other forms of blood letting. Medicare does not pay for finger sticks, heel sticks, etc., so they use the HCPCS code of G0001.Medi-Cal (California's version of Medicaid) uses their own special codes, mostly a heap of modifiers used by Medi-Cal alone. It's a ridiculous system that wastes money mostly on the denials and reams of paper to explain the denials, special forms to correct the denials, and special forms to inform of the acceptance or denials, and more forms to tell us of the status of a claim waiting to be handled. And none of these forms are uniform. But now Medi-Cal will be required to conform to the CPT modifiers, HCPCS codes, and claim format that every other insurer must use, and enable us to submit their claims electronically in the same format. In other words, HIPAA does not recognize state-mandated codes. Thank God, maybe California can save some of that Medi-Cal program's self-feeding money!!!
Is that where your HIPAA reference comes in, because I wasn't sure what "HIPAA codes" meant other than trying to delineate behavioral care and diagnostic codes. My understanding is that the HIPAA codes will bascially maintain the current CPT, ICD, and HCPCS codes and define more precise codes for behavioral health and other ill-defined areas.
It's important for you to familiarize yourself with the differences, and the reasons behind the differences, between CPT and HCPCS codes, and have updated versions at hand all the time.
I have not heard of commercial insurance codes changing; right now, they are using both CPT and HCPCS codes. Do you bill for a facility, or for physicians? Maybe that's where I'm confused, because if you asked me to jump in and start coding for a facility right now, I'd drown! 
[ 10-04-2003: Message edited by: law ]
