Question: Answer: Keep this CPT instruction in mind: "Don't choose a CPT code that merely approximates the service provided." This rule is key for compliant coding; however it leaves you with tough job of submitting a claim without a procedure-specific code. When you file a claim using an unlisted procedure code you should include a cover letter stating why you are using the unlisted code. This separate report should explain in simple straightforward language exactly what the physician did. In addition, you need to submit reporting documentation identifying the specifics of the procedure when you file the claim. The supplemental documentation should define the service (nature, extent, need) and the time, effort and equipment required. Other information to include: Unlisted procedure codes don't appear in the Medicare Physician fee Schedule, so they don't have assigned fees or global periods. Your payers will generally determine payment for unlisted procedure claims based on the documentation you provide. You can suggest a fee by comparing the unlisted procedure to a similar listed procedure with an established reimbursement value.