What Does the Three-Day Payment Window Bundle into an Inpatient Claim?

Is the Window 72 Hours or 3 Days?

It is calendar days, not hours. 42 CFR 412.2(c)(5) puts services on the date of admission and in the 3 calendar days immediately before it inside the inpatient payment, so the payment window covers four dates.

A lab draw at 12:30 am on Friday and an admission at 11:30 pm the following Monday are 95 hours apart, yet both dates sit inside the window. The reverse also holds: a service on the fourth day before admission falls outside it, even when the patient stayed in a continuous outpatient encounter. Claims Processing Manual chapter 3, section 40.3.B says such services are not part of the window and may not be bundled.

Which Outpatient Lines Move to the Inpatient Claim?

Sort every outpatient line by its revenue code. Section 40.3.B defines diagnostic services by the revenue and CPT codes on the bill, and everything else on a Part A patient from the admitting hospital is nondiagnostic.

The manual's diagnostic list is longer than the codes above. It also names 0254, 0255, 031X, 046X, 053X, 061X, 062X and 092X among others, so use the full list in section 40.3.B rather than a short version in your scrubber.

How Do You Move the Services onto the Inpatient Claim?

1. List every outpatient encounter with your hospital, and with any entity it wholly owns or operates, from the admission date back 3 calendar days.
2. Mark each line diagnostic or nondiagnostic using the revenue and CPT list in section 40.3.B.
3. For nondiagnostic lines on days 1 to 3, decide with the clinical team whether the service was unrelated to the admission. If it was, bill it separately with condition code 51, the attestation code, and keep the documentation in the chart.
4. For lines that stay inside the window, put the diagnoses, procedures and charges on the inpatient claim. Convert CPT codes to ICD-10-PCS and include only services that fall in the window.
5. Code every condition the patient had at the time of the inpatient order as present on admission, whether or not it was found while the patient was registered as an outpatient. See POA.
6. If an outpatient claim has already been paid, send an adjustment under chapter 3, section 50, and keep the Medicare filing limit of 1 calendar year after the date of service in view under 42 CFR 424.44.

How Does an Emergency Department Visit Fit In?

An ED visit on the day of admission goes on the inpatient claim. Section 40.3.D deems all outpatient nondiagnostic services on the admission date related to the stay, and revenue code 0450 is nondiagnostic. A separate OPPS ED claim for the same visit would conflict with the inpatient bill.

The professional side follows a different form but the same logic. Chapter 12, section 90.7 requires modifier PD on physician preadmission diagnostic and related nondiagnostic services billed by a practice the hospital wholly owns or operates. The hospital must tell the practice about the admission. Medicare then pays only the professional component of codes with a technical and professional split, and the facility rate for codes without one.

Whether a contracted ED group falls under that rule depends on the ownership or operation test in 42 CFR 412.2, so have compliance confirm it for each group. Our emergency medicine billing page covers how ED claims are built.

What Happens When Both Claims Reach Medicare?

The Common Working File rejects the outpatient diagnostic bill. Section 40.3.B says it checks the through date or last date of service, reported as occurrence span code 72, and the line item dates of service against the admission day and the 3 days before, regardless of which bill is processed first. The hospital must compare the two bills and report corrections.

Section 40.3.1 says separately billed non-physician services given the day before admission or during the stay are rejected as duplicates, and the hospital can be subject to sanction penalties under section 1128A of the Social Security Act. On the remittance, X12 defines CARC 18 as an exact duplicate and CARC 97 as a benefit included in the payment for another service. Match claim lines to dates before choosing which applies.

What Does a Monday Admission Look Like?

The inpatient claim then groups to one MS-DRG for all of these lines. The two-midnight decision that created the admission is in the two-midnight rule post.

What Should Registration and Billing Check up Front?

• Flag any patient admitted from the ED or observation, and pull the prior 3 days of outpatient encounters at the hospital and its owned practices.
• Hold outpatient claims for patients who are still in the ED or observation until the status decision is made.
• Confirm the hospital type. Hospitals and units outside the IPPS use a 1-day window, and critical access hospitals are outside the rule.
• Check the payer. This post covers Medicare fee-for-service. For Medicare Advantage and commercial plans, read the contract.
• Record why each nondiagnostic service is unrelated before condition code 51 goes on a claim.

Reference detail for these rules is in the three-day payment window rule page, and condition code 51 sits among the codes in our UB-04 codes post.

How Does Nucleus Align Handle Window Bundling?

Our hospital and facility billing team covers institutional claim preparation, revenue-code validation, submission, payment reconciliation and denial management for inpatient, outpatient and emergency care. See hospital and facility billing, the hospital revenue cycle guide, or book a call.