CO-117: Transportation to Nearest Facility

What Does CO-117 Mean?

CO-117 places the transportation cost difference on the provider as a contractual write-off. The payer considers the use of a non-nearest facility a coverage limitation, and under the CO designation, the provider cannot bill the patient for the denied amount. This is the standard pairing for transportation-related denials where the provider is responsible for verifying facility proximity before transport.

When CARC 117 appears on a remittance, the payer is telling you that the transportation service billed was to a facility that is not the nearest one capable of providing the patient's required care. Payers enforce this limitation to control transportation costs while ensuring patients still have access to appropriate medical services. The adjustment applies the coverage rule that transportation benefits are limited to the shortest reasonable distance to an adequate provider.

This code surfaces most often in ambulance and non-emergency medical transportation (NEMT) claims. The payer's system compares the destination facility against its network of providers and determines whether a closer facility could have delivered the same level of care. If a closer option exists, the claim for the additional distance is denied under CO-117. The denial does not necessarily mean the transportation was inappropriate — only that the payer's coverage policy limits reimbursement to the nearest qualifying facility.

Providers who routinely transport patients to specialized facilities that are not the closest option need robust documentation practices. A physician's certification of medical necessity, a written statement explaining why the nearest facility was inadequate, and records showing the patient's clinical requirements can all support an appeal. Without this documentation, the provider absorbs the cost as a contractual write-off.

Common Causes

How to Resolve

Verify whether the facility was the nearest appropriate option, gather supporting documentation, and appeal if the farther facility was medically necessary.

1. Confirm the facility was not the nearest appropriate option Verify the payer's nearest-facility determination and check whether the identified closer facility could actually provide the patient's required level of care.
2. Document medical necessity for the farther facility Gather physician certifications, clinical records, and any evidence showing the nearest facility lacked the required specialty, equipment, or capacity to treat the patient.
3. Correct any coding errors and resubmit or appeal If the denial was triggered by incorrect codes or modifiers, correct the claim and resubmit. If the coding is correct, file a formal appeal with the medical necessity documentation.
4. Write off if the facility choice was not medically justified If the nearest facility could have provided the needed care and the transport to a farther facility was not medically necessary, write off the denied amount as a contractual obligation.

Common RARC Pairings

The RARC code tells you exactly what triggered the CO-117:

How to Prevent CO-117

• Verify the nearest appropriate facility before scheduling transportation and document the rationale when a farther facility is selected
• Maintain a current database of facility capabilities to quickly determine the nearest option that can provide the required level of care
• Document medical necessity thoroughly for every transport to a non-nearest facility, including physician orders and clinical justification
• Obtain prior authorization when required by the payer for transportation to a facility beyond the nearest option
• Train dispatch and billing staff on payer-specific transportation coverage rules and distance limitations

General Prevention

• Verify the nearest appropriate facility before scheduling transportation services and document the rationale if a farther facility is medically necessary
• Document medical necessity thoroughly, including physician orders, patient condition details, and why alternative transportation methods are not suitable
• Ensure all claims include correct procedure codes, modifiers, and diagnosis codes before submission
• Obtain prior authorization from the payer when required for transportation services
• Train staff on payer-specific transportation coverage policies and distance limitations

Also Filed As

The same CARC 117 may appear with different Group Codes:

Related Denial Codes