PR 229 denial code

Claim adjustment reason code 229. Often reported as PR 229.

Medicare left part of a 12X bill aside

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 229 means

On a hospital claim first billed to Medicare as a 12X inpatient Part B bill, Medicare set part of the charge aside.

This is a coordination of benefits code used on outgoing claims to other payers, not a decision on its own. It carries forward the share of the charge that Medicare left out when the hospital billed the stay as inpatient Part B.

It is only used with group code PR. The supplemental or secondary payer will look at this amount when deciding its share.

Group codes seen with 229

On a remittance, 229 comes after a group code. These are the ones it is most often reported with:

• PR 229 (Patient Responsibility): The amount is assigned to the patient. Deductibles, coinsurance and copays are the everyday examples. Whether you can collect it still depends on your contract and the patient's plan.

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 hospital inpatient Part B claim left part of the charges unconsidered by Medicare.
• Secondary claim data carried over Medicare's treatment of the 12X bill.
• The inpatient stay was not covered under Part A and was billed on a 12X type of bill.

What to do next

1. Confirm the original Medicare claim was a 12X type of bill and review its remittance.
2. Bill the secondary or supplemental payer with the Medicare remittance data.
3. Check whether the remaining amount is the patient's after the secondary payer processes.

Related codes

• 23 (reason code) Prior payer payment affected this claim
• 22 (reason code) Another payer may be primary