Denial code CO-182: Procedure modifier invalid on the date of service
The modifier submitted was not valid, or not valid with that code, on the date the service was performed.
Procedure modifier was invalid on the date of service.
What CO-182 actually means
The same maintenance problem as CO-181, applied to modifiers. Modifiers are added, retired, and redefined, and payer-specific modifier policies change more often than the national code set. A modifier that was correct last year can invalidate an otherwise clean claim this year.
Why this denial happens
- A retired modifier is still in use in templates or macros.
- A modifier valid for one payer was used for a payer that does not recognise it.
- The modifier was not valid with the specific procedure code on that date.
- A modifier was used before its effective date.
How to resolve a CO-182 denial
- Verify the modifier’s validity for the date of service and for that payer.
- Replace it with the correct current modifier and resubmit.
- Update templates and macros carrying the retired modifier.
How to prevent it
- Review modifier changes with each annual code-set update.
- Maintain payer-specific modifier rules where they diverge from the national set.
Frequently asked
What does denial code CO-182 mean?
The modifier submitted was not valid, or not valid with that code, on the date the service was performed. The X12 description reads: "Procedure modifier was invalid on the date of service."
How do I fix a CO-182 denial?
Verify the modifier’s validity for the date of service and for that payer. Replace it with the correct current modifier and resubmit. Update templates and macros carrying the retired modifier.
Can CO-182 be billed to the patient?
Generally no. The recommended path for this code is "appeal or correct and resubmit" — check your payer agreement before transferring any balance to the patient.
Related denial codes
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General revenue-cycle guidance, not legal, coding, or payer-specific advice. Claim adjustment reason codes are maintained by X12 and are revised periodically; payer policy and your provider agreement govern in any specific case. Always read the remark codes transmitted with the denial — they frequently carry the detail this code does not.