Claim adjustment reason code
CO-167: Diagnosis is not covered
CO-167 means: This (these) diagnosis(es) is (are) not covered. The payer does not cover the condition you billed, whatever the procedure was.
Read the group code before you act on this
167 is the reason. The CO in front of it is the group code, a separate field on the remittance, and it is the one that decides who owes the money: CO means contractual obligation — the payer says the amount is not billable to anybody, and it is written off unless the denial itself is overturned. You may not bill the patient. What the other group codes mean.
What causes CO-167?
- A diagnosis excluded from the plan — cosmetic, experimental or a specific carve-out
- The most specific supporting diagnosis not sequenced first
- A screening diagnosis where the plan covers only diagnostic indications, or the reverse
- Coverage governed by a local or national coverage determination the diagnosis does not meet
How do you fix a CO-167 denial?
- Read the payer’s coverage policy for the procedure and find the diagnosis list it accepts.
- Check the chart for a covered diagnosis that the provider addressed and that was not sequenced first — do not add a diagnosis the note does not support.
- Where the note supports a covered indication, correct the sequencing and resubmit corrected.
- Where the condition genuinely is not covered, an advance beneficiary notice or a financial conversation is the right route, not a resubmission.
Can CO-167 be prevented?
Where a procedure has a coverage policy with a diagnosis list, check it before the service. Afterwards the only options are appeal or write-off.
A denial like this one is the recurring cost that medical billing outsourcing is built to take off your desk — a dedicated seat working the queue instead of it waiting for whoever has a free hour.
Who does this work
A medical coding seat at $2,500 per seat per month works this queue full time, during your business hours, inside your own system. Every call is logged with the payer reference number and the outcome, and every Friday you get it in writing.
Codes worked the same way
CO-167 is appealed with clinical documentation. So are these, which is why a queue sorted by recovery route moves faster than one sorted by code number — the same person, in the same system, with the same evidence to hand, clears all of them in one pass.
- CO-50 — Not deemed medically necessary
- CO-151 — Too many services billed
- CO-96 — Non-covered charges
- CO-170 — Provider type not paid
- CO-234 — Not paid separately
- CO-236 — Modifier combination not allowed
Specialties that name this among their costliest
These are specialties whose own worst denials include one of this kind. The line under each is the denial they name, quoted from their page so you can see what the link is based on.
- Pain ManagementRFA denied because the chart does not carry percent relief and duration from both diagnostic blocks
- OrthopedicsImplant and hardware charges denied for missing invoice documentation
- Behavioral HealthTime-based psychotherapy codes not supported by documented duration
- CardiologyStress tests denied for medical necessity documentation
- PodiatryAt-risk foot care documentation not naming the treating physician for the systemic condition
- Physical TherapyTimed code units not supported by documented treatment minutes
What leaving it costs
Working a denied claim costs $57.23 per denied claim in administrative time (source) — before any of it is recovered, and whether or not it ever is.
Payers ultimately pay roughly 90% of claims even while using an initial denial to slow payment (source), so the reason one sits is rarely that nobody knows how to work it. Put your own denial count in.
Questions
What does denial code CO-167 mean?
This (these) diagnosis(es) is (are) not covered. In plain terms: The payer does not cover the condition you billed, whatever the procedure was.
What causes CO-167?
A diagnosis excluded from the plan — cosmetic, experimental or a specific carve-out. The most specific supporting diagnosis not sequenced first. A screening diagnosis where the plan covers only diagnostic indications, or the reverse. Coverage governed by a local or national coverage determination the diagnosis does not meet.
How do you fix a CO-167 denial?
Read the payer’s coverage policy for the procedure and find the diagnosis list it accepts.. Check the chart for a covered diagnosis that the provider addressed and that was not sequenced first — do not add a diagnosis the note does not support.. Where the note supports a covered indication, correct the sequencing and resubmit corrected.. Where the condition genuinely is not covered, an advance beneficiary notice or a financial conversation is the right route, not a resubmission..
Can CO-167 be prevented?
Where a procedure has a coverage policy with a diagnosis list, check it before the service. Afterwards the only options are appeal or write-off.
Is CO-167 the same as PR-167?
Same reason, different group code. The number 167 is the reason: The payer does not cover the condition you billed, whatever the procedure was. The prefix says who carries the amount. CO means contractual obligation — the payer says the amount is not billable to anybody, and it is written off unless the denial itself is overturned. PR-167 is the same reason assigned to patient responsibility — the payer says the amount is owed by the patient, and it is billed to them. Read the prefix before the number: it decides whether you appeal, write off, or bill the patient.
What about the codes next to CO-167?
CO-166 and CO-168 are separate codes and this site does not yet cover them. The authoritative list is the X12 Claim Adjustment Reason Codes at x12.org/codes/claim-adjustment-reason-codes; a code is only described here once its official text, causes and fix have been written and checked.
Code descriptions are the standard X12 claim adjustment reason and remittance advice remark code text. Payer policies differ, and the payer’s own coverage policy governs any individual claim. This page is working guidance, not legal or clinical advice.
Last updated 2026-09-14. This is operational guidance drawn from payer remittance practice, not legal, coding or reimbursement advice. Payer-specific rules vary and change; confirm against the payer’s own policy before acting on a specific claim.
Other denial codes
- CO-96 — Non-covered charges
- CO-4 — Procedure code inconsistent with the modifier
- N34 — Incorrect claim form or format for this service
- CO-109 — Not covered by this payer or contractor
- CO-272 — Coverage or program guidelines not met
- PR-204 — Not covered under the patient’s current plan
- How to find payer underpayments nobody is looking for
- The five reasons certified payroll comes back rejected
- How to overturn a timely filing denial
Next step
Is CO-167 one of the denials costing you most?
Send a ninety-day denial report and an aged AR summary, with no patient identifiers. Within two working days you get a written summary of which denial reasons are costing you most and what is recoverable.
Or write to ops@softhomeglobal.com

