The UB-04 form, officially the CMS-1450, is the claim form that facilities use to bill for institutional services: hospitals, skilled nursing facilities (SNFs), hospices, rehabilitation facilities and home health agencies. Physicians and other practitioners bill their professional services on a different form, the CMS-1500. Most UB-04 claims are now sent electronically as the 837I, which carries the same information.
The form is maintained by the National Uniform Billing Committee (NUBC) and replaced the older UB-92. It has 81 form locators (FLs) that carry what a payer needs to process a facility claim: patient details, diagnosis codes, revenue codes, type of bill, discharge status, occurrence codes and provider information.
A single wrong entry, such as an incorrect revenue code, the wrong type of bill or a missing discharge status, can get the claim rejected, denied or paid late, so it pays to know which fields carry the most weight.
Which Healthcare Facilities Use the UB-04 Form?
The UB-04 applies to institutional providers, billing as a facility, not to individual practitioners. If you run a physician practice, your claims go on the CMS-1500; you will meet the UB-04 if your organization also runs a facility, such as a home health agency.
Facility Type | Uses UB-04? | Key Notes |
|---|---|---|
Acute Care Hospital | Yes | Inpatient and outpatient facility billing |
Skilled Nursing Facility (SNF) | Yes | Medicare Part A and post-acute care |
Inpatient Rehabilitation Facility | Yes | Stroke, orthopedic, neuro rehab claims |
Hospice Care Provider | Yes | Medicare hospice benefit billing |
Home Health Agency (HHA) | Yes | 30-day period-of-care claims under Medicare |
Behavioral Health Hospital | Yes | Psychiatric admissions and substance use |
Long-Term Care Hospital (LTCH) | Yes | Extended stays typically over 25 days |
Ambulatory Surgery Center | Sometimes | Medicare-certified ASCs bill Medicare on the CMS-1500; some other payers require the UB-04, and hospital outpatient surgery departments always use it |
Physician Clinic / Private Practice | No | CMS-1500 form is used instead |
Critical UB-04 Form Locators Every Biller Must Know
These are the fields with the most direct effect on whether a claim is accepted and paid correctly.
Type of Bill (FL 4)
A 3-digit code (entered in FL 4 after a leading zero) that tells the payer the type of facility, the type of care and where the claim sits in the stay. For example, 111 = Hospital Inpatient, Admit Through Discharge Claim; 131 = Hospital Outpatient, Admit Through Discharge Claim; 211 = Skilled Nursing Facility Inpatient, Admit Through Discharge Claim. A wrong type of bill can send the claim down the wrong processing path or get it rejected outright.
Revenue Codes (FL 42)
4-digit codes that identify the department or type of service behind each charge: for example, 0250 (Pharmacy), 0300 (Laboratory), 0420 (Physical Therapy), 0450 (Emergency Room). Each revenue code has to fit the HCPCS/CPT code beside it in FL 44, or the payer can suspend or deny the line.
Principal Diagnosis Code (FL 67)
The ICD-10-CM code for the condition chiefly responsible for the patient's care. On a Medicare inpatient claim it drives DRG (Diagnosis Related Group) grouping, so an invalid or incomplete code can group the stay wrongly and change what is paid.
Discharge Status (FL 17)
The patient's status at the end of the claim period: 01 = Discharged to home; 02 = Discharged/transferred to a short-term general hospital for inpatient care; 20 = Expired. It affects DRG payment and post-acute transfer payments, so it must match the clinical record. Payers review it closely.
Occurrence Codes & Dates (FL 31–34)
Codes and dates for events that affect payment: an accident date, the onset of symptoms, the date benefits were exhausted. A missing or wrong occurrence code can delay payment or lead to a denial, particularly on Medicare and Medicaid claims.
Attending Provider NPI (FL 76)
Required on almost every UB-04 claim (nonscheduled transportation claims are the exception). It takes the individual NPI of the attending physician; the facility's own NPI belongs in FL 56. Putting the facility NPI in FL 76 gets the claim rejected.
Most Common UB-04 Billing Errors — And How to Fix Them
Error Type | Claim Impact | How to Prevent It |
|---|---|---|
Wrong Type of Bill (FL 4) | Misrouted or rejected claim | Verify 3-digit TOB against payer policy per visit type and frequency |
Revenue code/HCPCS mismatch (FL 42 & 44) | Suspension or denial | Follow payer-specific revenue code-to-HCPCS crosswalks |
Invalid ICD-10 code (FL 67) | DRG grouping failure, medical necessity denial | Use updated ICD-10-CM codes and validate before submission |
Incorrect discharge status (FL 17) | Overpayment, audit risk | Match discharge status to the clinical record and post-acute plan |
Missing occurrence or condition codes | Payment delay or suspension | Review payer billing instructions for every care setting |
Facility NPI in attending provider field (FL 76) | Hard rejection | Always use the individual clinician’s NPI in FL 76–79 |
Inconsistent service dates (FL 6 vs FL 45) | Audit flag, suspicious billing | Reconcile Statement Period with individual service dates |
Two habits catch most of these. Scrub every UB-04 claim against payer edits before it goes out, and read your remittance advice for denials that repeat: the same error on several claims usually has one cause upstream, at registration, in coding or in the charge master.
UB-04 vs. CMS-1500: Key Differences
Which form you use depends on who provided the service, a facility or a practitioner, not on the payer. Many organizations bill both.
Criteria | UB-04 (CMS-1450) | CMS-1500 (HCFA) |
|---|---|---|
Used For | Hospitals, SNFs, hospices, institutional facilities | Physicians, clinics, individual providers |
Maintained By | National Uniform Billing Committee (NUBC) | National Uniform Claim Committee (NUCC) |
Number of Fields | 81 Form Locators | 33 Fields |
Electronic Equivalent | 837I (Institutional) | 837P (Professional) |
Medicare Applicability | Institutional claims under Part A and Part B (e.g., hospital outpatient) | Professional claims under Part B |
Typical Payers | Medicare, Medicaid, commercial facility plans | Medicare, Medicaid, commercial provider plans |
UB-04 and 837I Electronic Claim Submission
The 837I is the electronic version of the UB-04, the standard transaction for institutional claims under HIPAA. Facilities send 837I files through a clearinghouse or a direct connection to Medicare Administrative Contractors (MACs), state Medicaid programs and commercial payers.
What matters for getting paid is what comes back. The 999 acknowledgment confirms the file was received and readable, and the 277CA reports whether each claim was accepted for processing or rejected. A rejected claim never reaches adjudication, so someone has to watch these files, fix each rejection and resend it before the filing deadline.
Where Beeline fits
Beeline is a US company with a dedicated billing team. Its claims submission service builds and sends institutional claims on the UB-04 or 837I as well as professional ones, works rejections and follows each claim to a decision; the page's tool, "A claim's journey, stop by stop", shows where a claim can stall. Home health agencies can also see home health billing, and you can book a free consultation to have your claims looked at.
Frequently Asked Questions About the UB-04 Form
What is the UB-04 form used for in medical billing?
The UB-04 (CMS-1450) is used to submit institutional claims for hospital, SNF, hospice, rehabilitation, and home health services to Medicare, Medicaid, and commercial insurers. It contains 81 Form Locators that capture all data needed for facility-level reimbursement.
What is the difference between UB-04 and CMS-1500?
The UB-04 is for institutional providers (hospitals, SNFs, hospices) while the CMS-1500 is for professional providers (physicians, clinics). They use different fields and have different electronic equivalents (837I vs. 837P). In Medicare, the UB-04 carries institutional claims under both Part A and Part B (hospital outpatient services, for example), while the CMS-1500 carries professional Part B claims.
What are revenue codes on the UB-04 form?
Revenue codes are 4-digit numbers entered in FL 42 that identify the department or service type responsible for the charge. Common examples include 0300 (Laboratory) and 0450 (Emergency Room). A revenue code is required on every UB-04 service line, and on outpatient claims it is reported alongside the HCPCS code that drives APC payment.
Can UB-04 claims be submitted electronically?
Yes. The electronic equivalent of the UB-04 is the 837I, sent through a clearinghouse or a direct connection to the payer. Most institutional claims are sent this way today, and some payers accept paper only in limited cases.
What is a Type of Bill (TOB) on the UB-04?
The Type of Bill is a 3-digit code in FL 4 that identifies the facility type, service classification, and billing frequency. It determines how payers route and adjudicate the claim, so a wrong one can get the claim rejected.
Who maintains the UB-04 form?
The UB-04 is maintained by the National Uniform Billing Committee (NUBC) and adopted by the Centers for Medicare & Medicaid Services (CMS) for standardized institutional billing across the United States.
What are the most common UB-04 billing errors?
The most frequent errors include incorrect Type of Bill, revenue code and HCPCS mismatches, invalid or outdated ICD-10-CM codes, incorrect discharge status, missing occurrence or condition codes, and using a facility NPI where the attending physician’s individual NPI is required.
How does UB-04 billing affect DRG reimbursement?
The diagnosis and procedure codes entered on the UB-04 — especially in FL 67 (Principal Diagnosis) and FL 74 (Principal Procedure) — determine which Diagnosis Related Group (DRG) a Medicare inpatient claim groups into. Accurate coding directly determines the reimbursement amount for inpatient hospital stays.