CO-58 denial code
Treatment was deemed to have been rendered in an inappropriate or invalid place of service
How to fix it
Verify the place of service code is correct for where care was actually delivered, and correct if miscoded.
How to prevent it
Validate place of service codes during scrubbing, particularly for telehealth and off-campus locations where conventions change.
In practice
A behavioural health session is delivered in the patient's home and billed with place of service 11, the office code, because that is what the practice defaults to. The payer returns CO-58 and the line pays nothing.
Place of service is not a formality. It selects which of the two practice expense values in the fee schedule applies, and payers hold policies stating where particular services may be furnished at all. A home visit reported as an office visit fails on both counts.
Correcting the line to place of service 12 and resubmitting resolves it. The wider issue is that the default was never right for this provider's schedule, which means the same denial is already sitting in every other home visit billed that month.
What sits behind it
Telehealth is where this code has caused the most disruption, because the correct value has changed more than once. Place of service 02 and 10 now separate telehealth delivered outside the patient's home from telehealth delivered in it, and the two carry different payment. Practices that kept billing 02 for everything found the facility-rate reduction applied to visits that qualified for the higher non-facility rate.
Hospital-based and provider-based settings generate the second cluster. Codes 19 and 22 distinguish off-campus from on-campus outpatient departments, and a professional claim reporting the wrong one against a facility claim reporting the right one produces mismatches that both payers and auditors notice.
Because the value is usually inherited from a template or a scheduling location, CO-58 rarely arrives alone. Finding one is a reason to query every claim from the same location and provider over the preceding weeks rather than to correct a single line and move on.
Related codes
Terms used here — CMS-1500 · Claim Scrubbing · Denial
How we handle it — Medical Coding · Claims Management · Denial Management
Primary sources
The rules behind CO-58, at the bodies that publish them.
- Medicare Coverage Database (LCD/NCD) (opens in a new tab)
Centers for Medicare & Medicaid Services — Searchable national and local coverage determinations. The direct answer to whether a diagnosis supports medical necessity for a given procedure.
- Medicare Benefit Policy Manual (opens in a new tab)
Centers for Medicare & Medicaid Services — What Medicare covers and under what conditions, as distinct from how a claim is processed. The starting point for any coverage or medical necessity question.
- Advance Beneficiary Notice of Noncoverage (ABN) (opens in a new tab)
Centers for Medicare & Medicaid Services — The form and the rules for issuing it. Whether a non-covered service can be billed to the patient usually turns on whether a valid ABN was obtained beforehand.
Looking for a different code? Search all 190 CARC and RARC codes
Questions about CO-58
They approach the same mismatch from opposite ends. CO-5 says the procedure code is not payable in the setting reported. CO-58 says the payer considers the setting itself inappropriate for the treatment. In practice both are resolved by establishing where care actually happened and reporting that value accurately.
Code 10 when the patient is at home and code 02 when the patient is at any other originating site. The distinction matters financially because the two attract different practice expense values, so defaulting every telehealth claim to 02 leaves money on the table for home-based visits.
Yes, through a corrected claim, and it is worth doing in both directions. If the wrong value produced an underpayment the correction recovers it. If it produced an overpayment, self-reporting is far better than having it identified in an audit later.
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