CO-158: Service Provided Outside the United States
The payer excluded the service under international service provisions. You cannot bill the patient. Correct any billing errors, check for exceptions, or write off.
What Does CO-158 Mean?
CO-158 indicates the international service exclusion is a contractual provision — the provider cannot bill the patient for the denied amount. This most commonly results from a billing error (incorrect Place of Service code or address) that makes a domestic service appear international. If the denial is correct and the service was genuinely provided outside the U.S., the provider must absorb the write-off unless the plan has an emergency or special circumstance exception.
CARC 158 appears on your remittance when the payer has determined that the medical service or procedure was provided at a location outside the United States. Most domestic health insurance plans exclude or limit coverage for services rendered internationally, and CARC 158 is the denial code that enforces that exclusion.
The most common trigger in routine billing is a billing error — specifically an incorrect Place of Service code or provider address on the claim that indicates an international location. This can happen with telemedicine services, border-area providers, or when claims processing systems misinterpret a provider's address. Providers in U.S. territories (Puerto Rico, Guam, U.S. Virgin Islands, American Samoa) may also encounter this denial if the payer's system incorrectly classifies the territory as a foreign country.
When the service was genuinely provided outside the U.S., the resolution depends on the group code. Under CO, the provider absorbs the denial — this typically happens when the payer's contract excludes international services as a blanket provision. Under PR, the patient is responsible — common when the patient chose to seek care abroad and the plan assigns that cost to the patient. Some plans include emergency care exceptions for international services, so if the patient received emergency treatment while traveling, check whether the plan has a provision that waives the international exclusion for emergencies. Supplemental travel health insurance may also provide coverage.
Common Causes
| Cause | Frequency |
|---|---|
| Service genuinely rendered outside the United States The healthcare service was legitimately provided at a facility located outside U.S. borders, and the patient's insurance plan does not cover international services | Most Common |
| Billing error — incorrect Place of Service code The provider submitted the claim with a Place of Service code indicating the service was rendered outside the U.S. when it was actually provided domestically, or the address information on the claim points to a foreign location in error | Common |
| Provider located in a U.S. territory mistakenly flagged as international The provider is located in a U.S. territory (Puerto Rico, Guam, USVI, etc.) and the payer's system incorrectly classified the location as outside the United States | Common |
| Out-of-network international provider The patient received care from an international provider that is not in the payer's network, and the plan does not provide out-of-network coverage for services outside the U.S. | Common |
| Missing documentation for emergency care abroad The patient received emergency medical care outside the U.S. but the claim did not include documentation demonstrating it was an emergency, which some plans require to waive the international exclusion | Occasional |
How to Resolve
Determine whether the denial is due to a billing error or a genuine international service, then either correct the claim or pursue the appropriate resolution based on the group code.
- Check Place of Service and address Verify the Place of Service code and provider address on the claim. Correct any errors that incorrectly indicate an international location.
- Confirm U.S. territory coverage If the provider is in a U.S. territory, contact the payer to confirm coverage and submit documentation showing the service was provided within U.S. jurisdiction.
- Appeal with emergency documentation if applicable If the service was an international emergency, appeal with documentation showing the emergency nature of the care and reference any plan provisions for emergency services abroad.
- Write off if denial is upheld If the denial is correct and no exceptions apply, write off the amount as a contractual obligation.
Common RARC Pairings
The RARC code tells you exactly what triggered the CO-158:
| RARC | Description |
|---|---|
| N381 | Alert: The service is not covered due to policy exclusions for services outside the United States |
| N386 | This decision was based on plan exclusions or coverage limitations |
How to Prevent CO-158
- Verify Place of Service codes and provider addresses are accurate on every claim before submission
- Confirm with payers that U.S. territories are correctly classified as domestic in their claims systems
- Implement address validation checks for providers near international borders
- Train billing staff on the distinction between domestic and international Place of Service codes
General Prevention
- Verify that Place of Service codes and provider addresses are accurate on every claim before submission to prevent false international service flags
- Confirm with payers that U.S. territories are recognized as domestic locations in their claims processing systems
- For providers near international borders, implement address validation checks to ensure claims are not flagged as international in error
- Train billing staff on proper coding for services rendered at different locations, including the distinction between domestic and international service locations
- Verify patient coverage for international services before care is provided, especially for patients traveling abroad
Also Filed As
The same CARC 158 may appear with different Group Codes:
Related Denial Codes
Sources
- https://www.mdclarity.com/denial-code/158
- https://docs.claim.md/docs/claim-adjustment-reason-codes
- Codes maintained by X12. Visit x12.org for official definitions.