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CO-B17 Denial Code (Deactivated): Prescription Problems

CO-B17 meant payment was adjusted because the service lacked a proper prescription: not prescribed by a physician, not prescribed before delivery, incomplete, or not current. X12 deactivated it without naming a successor; codes 173 through 176 now cover each case.

X12 deactivated CARCB17 on February 1, 2006. Payers should no longer use it on new remittances, but it can still appear on older ERAs, corrected claims, and appeals.

Code: CO-B17 (CARC B17)
Status: Deactivated StoppedFebruary 1, 2006 (in use since January 1, 1995).
Code set: Claim Adjustment Reason Codes (CARC)
Group codes: CO (Contractual Obligation): Obtaining a valid order was the provider or supplier's responsibility, so the adjustment was not billed to the patient.
Official description: Payment adjusted because this service was not prescribed by a physician, not prescribed prior to delivery, the prescription is incomplete, or the prescription is not current.
X12 Claim Adjustment Reason Codes, retrieved September 25, 2026
Last verified: September 24, 2026 against the official X12 list.

What CO-B17 meant

CARC B17 was a prescription-related adjustment. Some services and supplies are payable only with a valid order, and this code told the provider that the order fell short in one of four ways: it did not come from a physician, it was written after the item or service was delivered, it was missing required elements, or it had expired.

What replaced it

No successor was named, but X12 created one code for each failure:

CO-173: not prescribed by a physician.
CO-174: not prescribed before delivery.
CO-175: prescription incomplete.
CO-176: prescription not current.

If you still see CO-B17

It should only appear on long-past claims. On a similar denial today, pull the order on file and compare it to the payer’s requirements: prescriber credentials, signature, date, item description, quantity, and length of need. If the order was valid but not sent, submit it with a reconsideration request. Build an order check into intake so items are not delivered before paperwork is complete.

CO-173 (Service/equipment was not prescribed by a physician.): Service or equipment was not prescribed by a physician.
CO-174 (Service was not prescribed prior to delivery.): Service was not prescribed prior to delivery.
CO-175 (Prescription is incomplete.): Prescription is incomplete.
CO-176 (Prescription is not current.): Prescription is not current.

CO-B17 FAQ

Which providers ran into CO-B17 most often?

Suppliers and services that depend on a written order, such as durable medical equipment, orthotics, therapy, and some diagnostic services.

Can a prescription be fixed after the fact?

An incomplete order can sometimes be completed by the prescriber, but a prescription dated after delivery usually does not cure a denial for lack of a prior order. Payer rules vary.

Important: read before using this information

This page is general educational information about a standard industry code set. It is not medical billing, coding, legal, reimbursement, or compliance advice, and it does not create a professional or advisory relationship with ClaimsRevenue.

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