UB-04 Billing: Bill Types, Revenue Codes, and Occurrence Codes Explained

The Institutional Claim Form, Decoded

If you work in facility billing, you deal with the UB-04 form (also called the CMS-1450). It is the institutional claim form used by hospitals, skilled nursing facilities, home health agencies, and other facilities to bill Medicare and other payers.

The UB-04 has fields that do not exist on the CMS-1500 (the form used by physician offices). Three of the most confusing are bill type codes, revenue codes, and occurrence codes. Here is what each one does and how to use them correctly.

Bill Type Codes (Form Locator 4)

The bill type is a 3-digit code that tells the payer what type of facility is billing and what type of claim this is.

First digit: Type of facility

• 1 = Hospital
• 2 = Skilled Nursing Facility
• 3 = Home Health
• 4 = Religious Nonmedical Health Care Institution
• 7 = Clinic
• 8 = Special Facility

Second digit: Bill classification

• 1 = Inpatient (including Medicare Part A)
• 2 = Inpatient (Medicare Part B only)
• 3 = Outpatient
• 4 = Other (intermediate care, laboratory)
• 8 = Swing bed

Third digit: Frequency/sequence

• 1 = Admit through Discharge (most common, single claim for entire stay)
• 2 = Interim First Claim (first of multiple claims for a long stay)
• 3 = Interim Continuing Claim
• 4 = Interim Last Claim
• 7 = Replacement of Prior Claim
• 8 = Void/Cancel Prior Claim

Common bill types you will see daily

• 111: Hospital inpatient, admit through discharge. The standard inpatient hospital claim.
• 112: Hospital inpatient, interim first claim. Used when a stay is long enough to require multiple claims (typically over 60 days).
• 121: Hospital inpatient, Medicare Part B only. When the patient is inpatient but the service is covered under Part B.
• 131: Hospital outpatient, admit through discharge. The standard outpatient hospital claim. Used for ER visits, outpatient surgery, observation stays, lab, radiology.
• 211: SNF inpatient, admit through discharge. Standard skilled nursing facility claim.
• 321: Home health, admit through discharge. Standard home health claim.
• 711: Clinic hospital-based. For hospital-based clinic services.
• 771: FQHC claim. Federally Qualified Health Center services.

Revenue Codes (Form Locator 42)

Revenue codes are 4-digit codes that categorize the type of service or department providing the service. Every line item on a UB-04 must have a revenue code.

Major revenue code categories

• 0100-0109: Room and Board (All-Inclusive). Used when the daily rate covers everything.
• 0110-0119: Room and Board (Private). Private room charges.
• 0120-0129: Room and Board (Semi-Private). Two beds per room.
• 0200-0209: Intensive Care. ICU charges.
• 0250-0259: Pharmacy. General pharmacy charges, drugs, and biologicals.
• 0260-0269: IV Therapy. IV solutions, supplies, and administration.
• 0270-0279: Medical/Surgical Supplies. Supplies and devices used in treatment.
• 0300-0309: Laboratory. Pathology and lab tests.
• 0320-0329: Radiology, Diagnostic. X-rays, CT scans, MRIs.
• 0350-0359: Operating Room. Surgical suite charges.
• 0370-0379: Anesthesia. Anesthesia services and supplies.
• 0450-0459: Emergency Room. ER facility charges.
• 0500-0509: Outpatient Services. General outpatient charges.
• 0510-0519: Clinic. Clinic visit charges.
• 0720-0729: Labor Room/Delivery. Obstetric facility charges.
• 0730-0739: EKG/ECG. Cardiac diagnostic services.
• 0800-0809: Behavioral Health Treatment. Inpatient psych services.
• 0940-0949: Other Therapeutic Services. Physical therapy, occupational therapy, speech therapy.

Revenue code 0001 is the total charge line. It appears as the last line on the claim and sums all other revenue code charges.

Occurrence Codes (Form Locator 31-34)

Occurrence codes are 2-digit codes that identify specific events related to the claim. They come with a date that tells the payer when the event happened.

Common occurrence codes

• 01: Accident date. When an injury from an accident occurred.
• 04: Date of planned admission. When a planned admission was originally scheduled.
• 05: Date benefits exhaust. When a specific benefit period ends.
• 11: Onset of symptoms/illness. When the patient first experienced symptoms related to this claim.
• 17: Date of occupational therapy plan. When the OT treatment plan was established.
• 18: Date of retirement of patient/beneficiary. When the patient retired (affects coverage).
• 27: Date of hospice certification. When hospice was certified/recertified.
• 31: Date beneficiary notified of intent to bill. Important for ABN (Advance Beneficiary Notice) situations.

Occurrence Span Codes (Form Locator 35-36)

Similar to occurrence codes but represent a date range (from/through) instead of a single date.

Common occurrence span codes

• 70: Qualifying stay dates. The dates of a prior qualifying hospital stay for SNF admission. Medicare requires a 3-day qualifying inpatient stay before covering SNF services.
• 71: Prior stay dates. Dates of a prior related hospital stay.
• 72: First/last visit dates. The dates of the first and last visits in a billing period.
• 74: Non-covered level of care. Dates when the patient was receiving a level of care not covered by their plan.

Condition Codes (Form Locator 18-28)

Condition codes identify circumstances that affect claim processing.

Common condition codes

• 01: Military service related. The condition is related to military service.
• 02: Condition is employment related. Workers' comp.
• 04: Information only bill. Not a request for payment.
• 07: Treatment of non-terminal condition for hospice patient. When a hospice patient is treated for something unrelated to their terminal diagnosis.
• 20: Beneficiary requested billing. Patient asked the provider to bill Medicare even though the service may not be covered (ABN on file).
• 40: Same-day transfer. Patient was transferred to another facility on the day of admission.

Common UB-04 Mistakes

1. Wrong bill type code. Using 131 (outpatient) when the patient was admitted as inpatient (111). This changes how the entire claim is processed and paid.
2. Missing revenue codes. Every service line needs a revenue code. Missing one causes the line to reject.
3. Wrong occurrence span code 70 dates. If the qualifying stay dates for SNF are wrong, the SNF claim gets denied. Triple-check these.
4. Not including condition code 07 for hospice patients. When a hospice patient is treated for a non-terminal condition at a hospital, condition code 07 must be on the claim or it gets denied.

Have a UB-04 billing question? Ask Pika and get the right bill type, revenue code, or occurrence code with plain English explanations.