UB04 Type of Bill Code 0131: Hospital Outpatient - Admit through Discharge Claim

Overview

The UB-04 Type of Bill code 0131 is a four-digit alphanumeric code that indicates a hospital outpatient claim covering the entire episode of care from admission through discharge. According to the Noridian Bill Types guide, the code structure breaks down as follows: the first digit (0) is a leading zero ignored by CMS; the second digit (1) signifies the type of facility is “Hospital”; the third digit (3) denotes the type of care as “Outpatient (except Clinics)”; and the fourth digit (1) represents the frequency/sequence “Admit Through Discharge” ^[1]. This code is used when a single claim is submitted for an entire outpatient stay, from the patient’s arrival (admission) to departure (discharge), without needing interim or late-charge claims. The MassHealth UB-04 Billing Guide confirms that acute outpatient hospitals (including hospital-licensed health centers) use the UB-04 form for such claims ^[2]. Because the frequency digit “1” explicitly means “Admit Through Discharge,” providers must ensure the claim covers the complete outpatient service period and does not require subsequent billings for the same encounter.

When to Use

Use Type of Bill 0131 when a hospital provides outpatient services that begin and end within a single billing cycle, and the entire episode is captured on one claim. This applies to, for example, outpatient surgery, diagnostic testing, observation stays, or emergency department visits that do not result in inpatient admission. The Noridian Bill Types guide specifies that the fourth digit “1” is for “Admit Through Discharge,” meaning the claim is a final and complete bill for the full outpatient encounter ^[1]. Do not use this code if the claim is interim (first, continuing, or last – codes 2, 3, 4), a late charge only (code 5), or a replacement/void (codes 7, 8). The MassHealth UB-04 guide emphasizes that acute outpatient hospitals must use the UB-04 form for paper claims, and code 0131 is appropriate when submitting such a claim for a complete outpatient service ^[2]. Additionally, because the facility digit “1” indicates “Hospital,” this bill type is not valid for skilled nursing facilities, clinics, or home health agencies. Providers should verify that the claim does not need to be split into multiple interim bills; if the outpatient stay crosses multiple billing periods, interim codes (0132, 0133, 0134) would be required instead.

Step-by-Step Claim Example

Consider a patient who visits a hospital outpatient department for a same-day knee arthroscopy. The patient arrives at 8:00 AM, undergoes the procedure, and is discharged at 4:00 PM the same day. The hospital submits a single UB-04 claim for the entire encounter. In Field 4 (Type of Bill), the code entered is 0131 – the leading zero, “1” for hospital, “3” for outpatient, and “1” for admit through discharge ^[1]. The claim includes patient demographic data (Field 3, 5, etc.), dates of service (Field 6 – Statement Covers Period) showing the single day 01/15/2025 through 01/15/2025, and revenue codes (Field 42) such as 0360 (Operating Room Services) and 0250 (Pharmacy). The total charges are entered in Field 47. Since the claim is an admit-through-discharge bill, no interim billing numbers are needed. The patient status code in Field 17 is set to “01” (discharged to home) ^[2] notes that the UB-04 form must be completed according to their instructions, including all required fields. After the claim is submitted, the payer processes it as a single outpatient episode. If the hospital had instead performed the procedure over two days with separate billing periods, interim codes (e.g., 0132 for the first claim) would have been necessary. This example illustrates the correct use of 0131 for a complete, one-time outpatient stay.

Common Mistakes & Audit Red Flags

A frequent error is using 0131 when the outpatient stay requires multiple claims, such as when services span consecutive months or when late charges are added after the original claim. The Noridian Bill Types guide clearly distinguishes frequency “1” (Admit Through Discharge) from “2” (Interim – First Claim), “3” (Interim – Continuing), and “4” (Interim – Last Claim) ^[1]. Submitting 0131 for a partial stay or for a claim that will later be followed by late charges (frequency “5”) will likely cause the payer to reject or adjust the claim. Another red flag is using 0131 for a non-hospital facility; for example, a clinic or skilled nursing facility must use a different second digit (e.g., “7” for clinic or “2” for SNF). The MassHealth guide stresses that only acute inpatient and outpatient hospitals use the UB-04 for paper claims, so misidentifying the facility type on the bill can lead to denials ^[2]. Additionally, auditors look for inconsistent use of revenue codes: if the bill type says “outpatient” (digit 3), but the claim contains revenue codes that are only valid for inpatient stays (e.g., room and board charges), it flags a potential billing error. Providers should also ensure that the statement covers period (Field 6) matches the “admit through discharge” concept – a single date or a short, contiguous range. Using 0131 for a claim that covers multiple separate outpatient visits (without an admission/discharge construct) is another compliance risk, as the frequency “1” implies a single stay.

Related Codes/Fields

The table below lists related Type of Bill codes (for hospital outpatient) and other key UB-04 fields that frequently interact with code 0131. Information is derived from the Noridian Bill Types guide ^[1] and the MassHealth UB-04 guide ^[2].

Form Locator (FL)	Field Name	Code/Value	Meaning
FL 4	Type of Bill	0131	Hospital Outpatient – Admit Through Discharge
FL 4	Type of Bill	0132	Hospital Outpatient – Interim First Claim
FL 4	Type of Bill	0133	Hospital Outpatient – Interim Continuing Claim
FL 4	Type of Bill	0134	Hospital Outpatient – Interim Last Claim
FL 4	Type of Bill	0135	Hospital Outpatient – Late Charge Only
FL 4	Type of Bill	0137	Hospital Outpatient – Replacement of Prior Claim
FL 4	Type of Bill	0138	Hospital Outpatient – Void/Cancel of Prior Claim
FL 4	Type of Bill (facility digit)	1xx	Type of facility = Hospital
FL 4	Type of Bill (care digit)	x3x	Type of care = Outpatient (except Clinics)
FL 4	Type of Bill (frequency digit)	xx1	Frequency = Admit Through Discharge
FL 6	Statement Covers Period	(dates)	Must reflect the single outpatient stay for code 0131
FL 17	Patient Status Code	e.g., 01	Discharge status (e.g., home) – required for admit-through-discharge claims
FL 42	Revenue Codes	e.g., 0450, 0451	Emergency room, etc. - must align with outpatient nature of claim

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References

[1] Noridian Bill Types — https://med.noridianmedicare.com/web/jea/topics/claim-submission/bill-types

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