UB04 Admission Hour Code 08: 08:00 AM - 08:59 AM

Overview

Code 08 on the UB-04 claim form indicates that the patient’s admission or start of care occurred between 08:00 AM and 08:59 AM. This code is part of the admission hour field (Field 13), which uses military time (00–23) to record the exact hour of admission. According to CMS guidelines, Field 13 is required on inpatient bills only and must contain the date of admission or start of care, along with the corresponding hour code. ^[1] specifies that code 00 represents 12:00 AM (midnight), 01 represents 1:00 AM, and so on, with 23 representing 11:00 PM. Code 08 specifically covers the hour from 8:00 AM through 8:59 AM. This code is essential for accurate billing and claims processing, as it helps payers determine the correct admission timing for inpatient stays or outpatient care initiation.

When to Use

Use code 08 when the patient’s admission or start of care occurs between 08:00 AM and 08:59 AM on the date recorded in Field 13. This applies to inpatient hospital admissions, outpatient observation services, or any other care that requires a start-of-care date and hour. For example, if a patient is admitted to the hospital at 8:30 AM on March 15, 2024, the provider would enter the admission date (03/15/2024) in Field 13 and code 08 in the admission hour field. The code must be used consistently with the military time format—08 represents 8:00 AM through 8:59 AM, not 8:00 PM (which would be code 20). ^[1] emphasizes that the admission hour code is required on inpatient bills onlyhol. Providers should verify that the admission time documented in the medical record matches the code submitted to avoid claim denials or audits. The MassHealth guide reiterates that all claims must be submitted electronically unless an exemption is granted, but the same coding rules apply. ^[2]

Step-by-Step Claim Example

Scenario: A patient is admitted to the hospital at 8:45 AM on June 10, 2024, for inpatient care.

1. Field 13 – Admission/Start of Care Date: Enter the date as 06/10/2024 (MM/DD/YYYY format).
2. Admission Hour Code: Enter code 08 in the designated hour field (typically a two-digit box adjacent to the date). This indicates the admission occurred between 8:00 AM and 8:59 AM.
3. Verify Military Time: Confirm that 8:45 AM corresponds to code 08, not 20 (which would be 8:00 PM). ^[1]
4. Complete Remaining Fields: Fill out other required fields such as patient name, insurance information, diagnosis codes, and revenue codes according to payer guidelines.
5. Submit Claim: Submit the claim electronically (as required by MassHealth) or via paper if an exemption is approved. ^[2]

Example Claim Data:

• Field 13: 06/10/2024
• Admission Hour: 08

Common Mistakes & Audit Red Flags

• Using code 08 for 8:00 PM: A frequent error is confusing AM and PM. Code 08 is for 8:00 AM–8:59 AM; 8:00 PM requires code 20. ^[1]
• Omitting the admission hour code: Some providers leave the hour field blank, which can cause claim rejection or delay. Field 13 requires both the date and the hour code for inpatient bills.
• Mismatch with medical records: If the medical record shows admission at 8:30 AM but the claim uses code 09 (9:00 AM–9:59 AM), auditors may flag the discrepancy as a potential billing error.
• Using code 08 for outpatient services incorrectly: While the hour code is required for inpatient bills, some payers may also request it for observation or outpatient care. Check payer-specific requirements. ^[2]
• Incorrect date format: Ensure the date in Field 13 matches the admission hour code. For example, if admission is at 8:45 AM on June 10, the date must be 06/10/2024, not 06/11/2024.

Related Codes/Fields

Code/Field	Description	Source
Code 00	12:00 AM – 12:59 AM (midnight hour)	[1]
Code 01	1:00 AM – 1:59 AM	[1]
Code 07	7:00 AM – 7:59 AM	[1]
Code 09	9:00 AM – 9:59 AM	[1]
Code 20	8:00 PM – 8:59 PM	[1]
Field 13	Admission/Start of Care Date (required on inpatient bills)	[1]
Field 14	Priority of Admission (e.g., emergency, urgent, elective)	[2]

| Field 15

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References

[1] CMS R1915CP — https://www.cms.gov/Regulations-and-Guidance/Guidance/Transmittals/downloads/R1915CP.pdf

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