UB04 Field 9: Patient Address

UB-04 Field 9: Patient Address is a required data element used to identify the physical or mailing location of the individual receiving healthcare services. While it appears straightforward, this field is a primary data point for payer identity verification and eligibility cross-referencing.

Overview

Field 9 (also known as Form Locator 09) is located on the top left portion of the UB-04 (CMS-1450) claim form, immediately below the patient's name in Field 8. It captures the patient's full mailing address, including the street address, city, state, and ZIP code.

The field is divided into five sub-sections (9a through 9e) on the paper form to accommodate:

• 9a: Street Address
• 9b: City
• 9c: State (2-character abbreviation)
• 9d: ZIP Code (5 or 9 digits)
• 9e: Country Code (if applicable)

For electronic claims (837I), this data maps to the 2010CA Loop (Patient Name and Address). Payers use this information to match the claim against their member enrollment files. Any discrepancy between the address on the claim and the address in the payer's system can trigger a "Member Not Found" or "Eligibility Mismatch" rejection.

When to Use This Field

Field 9 is Required for all institutional claims, including inpatient, outpatient, and home health services. It must be populated regardless of whether the patient is the primary policyholder (subscriber) or a dependent.

Specific Billing Scenarios

1. Dependent Care: When billing for a child covered under a parent's policy, Field 9 must reflect the child's current residence. If the child lives at a different address (e.g., a student away at college), the address in Field 9 will differ from the subscriber address in Field 38.
2. Homeless Patients: If a patient is homeless, facilities should follow state-specific Medicaid or Medicare guidelines. Often, the facility's address or a "No Fixed Address" notation is used, but this must be verified with the local MAC or payer to avoid automatic OCR (Optical Character Recognition) rejections.
3. International Patients: For patients residing outside the U.S., Field 9e must contain the appropriate ISO country code. Failure to include the country code for a foreign address will cause the claim to fail standard validation edits.

Step-by-Step Claim Example

Patient Scenario

A patient, Sarah Miller, receives emergency appendectomy services at an acute care hospital. Sarah is a dependent on her spouse’s employer-sponsored health plan. Her legal residence is 456 Maple Avenue, Apt 4B, Chicago, IL 60601.

Field Values

• Field 8b (Patient Name): MILLER, SARAH
• Field 9a (Street Address): 456 MAPLE AVENUE APT 4B
• Field 9b (City): CHICAGO
• Field 9c (State): IL
• Field 9d (ZIP): 60601-1234
• Field 38 (Responsible Party): MILLER, ROBERT (Subscriber Address: 456 MAPLE AVENUE APT 4B, CHICAGO, IL 60601)

Payer Response

The claim is submitted to the commercial payer. The adjudication system compares Field 9 against the member's enrollment record. Because the address matches the "Member Address" on file exactly, the claim passes the initial demographic scrub. If the hospital had used an old address from a previous visit, the payer would issue a CO-16 denial (Claim/service lacks information or has submission/billing error) with Remark Code MA27 (Incomplete/invalid patient address).

Common Mistakes & Audit Red Flags

• P.O. Box Restrictions: Many payers, particularly Medicare, require a physical residential address for the patient. Using a P.O. Box in Field 9 when a physical address is available can trigger a rejection, as the address is used to determine the correct Medicare Secondary Payer (MSP) and regional pricing CMS Pub. 100-04 Chapter 25.
• ZIP Code Mismatches: Entering a 5-digit ZIP code when the payer's system requires the ZIP+4 can lead to "invalid address" errors in automated clearinghouses.
• Truncated Data: On paper claims, if the street address is too long and spills into Field 9b, OCR scanners will misread the city. Always use standard USPS abbreviations (e.g., "STE" for Suite, "APT" for Apartment) to keep data within the designated boxes NUBC UB-04 Manual.
• Inconsistency with Field 38: While the patient and subscriber addresses can be different, a mismatch for a patient who is also the subscriber is a major red flag for identity theft or fraudulent billing.

Related Codes & Fields

• Field 8: Patient Name
• Field 10: Patient Birthdate
• Field 38: Responsible Party Name and Address
• Field 58: Insured’s Name
• Field 60: Insured’s Unique ID

References

1. CMS Pub. 100-04 Chapter 25
2. NUBC UB-04 Manual