OA P6 denial code

Claim adjustment reason code P6. Often reported as OA P6 or CO P6.

Based on entitlement to benefits

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 P6 means

On a property and casualty claim, the payment decision rests on whether, and how far, the patient is entitled to benefits.

You will see it only on property and casualty remittances, for example from a workers' compensation or auto carrier. P6 says the result turns on the claimant's entitlement, for example whether coverage applies, how much of a benefit remains, or which benefits the claimant qualifies for.

A rule or policy reference may come with it on the remittance. The adjuster is usually the best source for exactly which entitlement issue applied.

Group codes seen with P6

On a remittance, P6 comes after a group code. These are the ones it is most often reported with:

• OA P6 (Other Adjustment): Used for adjustments that are neither the provider's contractual write-off nor the patient's share. It often appears with coordination of benefits, for example when another payer already paid.
• CO P6 (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

• Benefits under the policy were limited or exhausted for this claimant.
• The claimant was not entitled to the type of benefit billed.
• Entitlement was still being determined when the claim processed.

What to do next

1. Call the adjuster to learn which entitlement issue affected the claim.
2. Check whether another payer, such as the patient's health plan, should be billed next.
3. Resubmit or appeal once entitlement is confirmed or corrected.

Related codes

• P8 (reason code) Claim under investigation
• P4 (reason code) Workers' comp claim found non-compensable
• 109 (reason code) Not covered by this payer, send elsewhere