UB04 Type of Bill Code 0321: Home Health - Inpatient (Plan of Care) - Admit through Discharge Claim

Overview

Code 0321 is a four‑digit Type of Bill (TOB) used on the UB‑04 claim form. The leading zero is ignored by CMS, the second digit 3 identifies the facility type as Home Health, the third digit 2 indicates Inpatient Part B (the type of care), and the fourth digit 1 means the claim covers the entire stay from admit through discharge (frequency code 1) ^[1]. The MassHealth UB‑04 guide notes that all paper claims must follow the standard UB‑04 format and that providers must use the correct code sets ^[2]. Understanding the digit structure helps prevent billing errors and ensures proper reimbursement.

When to Use

^[1]. The MassHealth UB‑04 guide emphasizes that providers must select the correct code set to avoid claim rejections ^[2]. Always verify that the patient’s admission and discharge dates fall within the same billing period and that the plan of care is active for the entire stay.

Step‑by‑Step Claim Example

A home health agency provides inpatient skilled nursing and physical therapy to a patient under a physician‑approved plan of care. The patient is admitted on January 1, 2025, and discharged on January 15, 2025. The agency bills a single UB‑04 claim with the following key fields:

• Field 4 – Type of Bill: Enter 0321 (Home Health – Inpatient – Admit Through Discharge) ^[1].
• Field 6 – Statement Covers Period: From 01/01/2025 to 01/15/2025.
• Field 8 – Patient Name: John Doe.
• Field 9 – Patient Address: 123 Main St.
• Field 10 – Patient Birth Date: 01/01/1950.
• Field 11 – Patient Sex: M.
• Field 12 – Admission Date: 01/01/2025.
• Field 13 – Admission Hour: 10 (10:00 AM).
• Field 14 – Type of Admission: 1 (Emergency) or as appropriate.
• Field 15 – Source of Admission: 1 (Physician referral).
• Field 16 – Discharge Hour: 14 (2:00 PM).
• Field 17 – Patient Discharge Status: 01 (Discharged to home or self‑care).
• Field 42 – Revenue Codes: List applicable revenue codes (e.g., 0420 for physical therapy, 0550 for skilled nursing).
• Field 43 – Revenue Description: Corresponding descriptions.
• Field 44 – HCPCS/Rates: CPT/HCPCS codes for each service.
• Field 45 – Service Dates: Individual dates of service if needed.
• Field 46 – Units: Number of units per service.
• Field 47 – Total Charges: Sum of all charges.
• Field 50 – Payer Name: Medicare Part B (or other payer).
• Field 51 – Health Plan ID: Payer’s identifier.
• Field 52 – Release of Information: Signed.
• Field 53 – Assignment of Benefits: Signed.

The claim is submitted as a single “admit through discharge” bill. The MassHealth UB‑04 guide provides general instructions for completing all fields, including the requirement to use valid code sets ^[2]. After submission, the payer processes the claim based on the plan of care and the inpatient Part B benefit.

Common Mistakes & Audit Red Flags

• Using the wrong frequency digit: Code 0321 requires frequency 1 (admit through discharge). Using 2 (interim first), 3 (interim continuing), or 4 (interim last) will cause the claim to be rejected or misrouted ^[1]. Always verify that the entire stay is billed on one claim.
• Billing for outpatient home health services: Code 0321 is for inpatient Part B services. If the patient is not formally admitted as an inpatient, use a different TOB (e.g., 0331 for home health outpatient). Auditors will check admission and discharge dates against the plan of care.
• Missing or incomplete plan of care: The “plan of care” is a required element. Without a signed physician’s plan, the claim may be denied. The MassHealth guide stresses that all documentation must support the services billed ^[2].
• Incorrect revenue codes or HCPCS: Using revenue codes that do not match the inpatient setting (e.g., using outpatient therapy codes) can trigger audits. Ensure revenue codes align with inpatient Part B guidelines.
• Duplicate billing: Submitting both an interim claim and a final claim with frequency 1 for the same period is a red flag. Code 0321 should be the only claim for that episode.
• Date range errors: The statement covers period must exactly match the admission and discharge dates. Discrepancies may lead to recoupment.

Related Codes/Fields

The table below lists other Type of Bill codes for home health and related fields that often appear with code 0321.

Code / Field	Description	Source
0311	Home Health – Inpatient Part A – Admit Through Discharge	[1]
0322	Home Health – Inpatient Part B – Interim – First Claim	[1]
0323	Home Health – Inpatient Part B – Interim – Continuing	[1]
0324	Home Health – Inpatient Part B – Interim – Last Claim	[1]
0325	Home Health – Inpatient Part B – Late Charge Only	[1]
0331	Home Health – Outpatient – Admit Through Discharge	[1]
Field 12 – Admission Date	Required for inpatient claims; must match the start of the statement period	[2]
Field 17 – Patient Discharge Status	Indicates where the patient is discharged; must be consistent with the plan of care	[2]
Field 42 – Revenue Codes	Used to detail each service line; for inpatient home health, common codes include 042x (therapy) and 055x (skilled nursing)	[2]

Always cross‑reference the TOB with the patient’s admission status and the plan of care to ensure correct billing.

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References

[1] Noridian Bill Types — https://med.noridianmedicare.com/web/jea/topics/claim-submission/bill-types

[2] MassHealth UB-04 Guide — https://www.mass.gov/doc/ub-04-billing-guide-0/download