UB04 Field 12: Admission Date

Introduction

UB-04 Field 12, also referred to as Box 12, is used to record the Admission Date for the patient's current episode of care. This field is a critical data element for both inpatient and outpatient facility billing, as it establishes the start of the clinical encounter for insurance adjudication.

Requirements

Requirement Type	Status
Inpatient Requirement	Required
Outpatient Requirement	Required
Field Name	Admission Date
Data Format	Six-digit format (MMDDYY)

Billing Tips

When completing Box 12, ensure the date is formatted strictly as MMDDYY without slashes or dashes. For inpatient claims, this date must align with the date the patient was formally admitted to the facility. For outpatient services, this typically represents the date the patient first arrived for treatment or the start of the service period.