CO 267 denial code

Claim adjustment reason code 267. Often reported as CO 267.

Claim spans more than one month

Unofficial reference. This is our own plain-English explanation, not the official code text. Payer rules differ. Verify with the payer and the official X12 code list. AlphaPrefix is not affiliated with X12, CMS or any payer. Data last updated Nov 11, 2026.

What 267 means

The claim or service covers dates in more than one month, which the payer cannot process as billed.

Some payers, programs, and service types need claims split by month, for example for monthly billing cycles, monthly authorizations, or rate changes. This code tells you the date span crossed a month boundary.

A remark code is required with it and usually clarifies the payer's rule. Splitting the claim by month typically solves it.

Group codes seen with 267

On a remittance, 267 comes after a group code. These are the ones it is most often reported with:

• CO 267 (Contractual Obligation): The provider's side of the ledger. The reduction comes from the payer contract or a rule the provider has to follow, and the patient normally cannot be billed for it.

The payer chooses the group code for each adjustment, so the same reason code can appear with another group code on your remittance. Read the two together. More about group codes.

Common causes

• A recurring or series service was billed with a from and through date that crossed into a new month.
• The payer's authorization or rate is set per month.
• An institutional claim covering a long stay was not split as the payer requires.

What to do next

1. Read the remark code for the payer's specific rule.
2. Split the services into separate claims or lines by month.
3. Check authorizations for each month before resubmitting.
4. Update the billing setup so recurring services are cut off at month end for that payer.

Related codes

• 268 (reason code) Claim crosses into a new year
• 16 (reason code) Missing information or billing error