CO 60 denial code

Claim adjustment reason code 60. Often reported as CO 60.

Outpatient care near an inpatient stay

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 60 means

Outpatient services given shortly before, during or after an inpatient stay were not paid separately.

Some payers fold outpatient services that happen close to an inpatient admission into the inpatient payment. When that applies, the outpatient claim is denied or adjusted with this code and the services belong on the inpatient claim.

How close the services must be, and which services count, depends on the payer's rules. Check the payer's policy before rebilling.

Group codes seen with 60

On a remittance, 60 comes after a group code. These are the ones it is most often reported with:

• CO 60 (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

• Diagnostic tests or treatment were done as an outpatient shortly before an admission at the same facility.
• The outpatient claim was sent separately instead of being combined with the inpatient claim.
• The admission date was not known when the outpatient claim was billed.

What to do next

1. Check whether the patient had an inpatient stay near the outpatient date of service.
2. Read the payer's rules on which outpatient services are included in the inpatient payment.
3. Add qualifying outpatient charges to the inpatient claim and send a corrected claim if needed.
4. Appeal if the outpatient service was unrelated to the admission and the payer allows that exception.

Related codes

• MA133 (remark code) Dates fall inside an inpatient stay
• M2 (remark code) Patient was an inpatient at the time