CurrentUnitedHealthcarePolicy 2026R0123B

Ambulance transportation reimbursement on CMS-1500

Defines UnitedHealthcare's reimbursement rules for ambulance services billed on the CMS-1500 form (including modifier, bundled services, ALS2, and supplier eligibility) for Commercial and Individual Exchange plans.

Policy Summary

PayerUnitedHealthcare

PolicyAmbulance transportation reimbursement on CMS-1500

Policy CodePolicy 2026R0123B

Change TypeNo material change

Effective Date

Next Review Date

Key ActionReport ambulance transportation codes only when accompanied by a valid two-character origin-destination modifier to avoid denial.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

CMS 1500claim form governed

A0021–A0999HCPCS range used for ambulance services

Two-digitambulance origin/destination modifier required

ALS2 criteriaALS2 definition

Same TINbundled codes rule

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Coverage criteria for ambulance services

UnitedHealthcare reimburses ambulance transportation codes when reported by eligible Ambulance Suppliers with correct two-character origin–destination modifiers and when services meet the applicable clinical and billing criteria (including ALS level requirements).

ALL of the following

Service must be reported by an Ambulance Supplier to be eligible for reimbursement.
A valid two-character origin–destination ambulance modifier must accompany each ambulance transportation code; ambulance transportation services reported without a valid two-digit ambulance modifier will be denied.
When 'X' (intermediate stop at physician's office) appears in the two-digit modifier combination, 'X' must be in the second position and must be preceded by a valid origin digit; if 'X' is the first digit the code will be denied.
Services listed on the Ambulance Bundled Codes list (services included in ambulance transportation such as oxygen, drugs, extra attendants, supplies, EKG, night differential, and customary equipment) are not paid separately when provided by the Same Ambulance Supplier on the same date of service as an Ambulance Transportation Code.
Ambulance transports to/from an originating facility for diagnostics or specialty treatment that overlap an inpatient stay (excluding admission and discharge dates) are not separately reimbursable; payment is the responsibility of the originating facility.
ALL of the following
- Reimbursement is based on the level of service provided (BLS, ALS1, ALS2), not on the vehicle used.
- ALS2 criteria (one of)
  - At least three separate administrations of one or more medications by intravenous push/bolus or by continuous infusion (excluding crystalloid fluids).
  - Provision of at least one of the specified ALS2 procedures: manual defibrillation/cardioversion; endotracheal intubation; central venous line; cardiac pacing; chest decompression; surgical airway; or intraosseous line.

Non‑Ambulance Suppliers reporting HCPCS ambulance codes (A0021 and A0225–A0999) will not be reimbursed.

Ambulance Codes and Coding Rules

Ambulance Transportation CodesHCPCS

A0021-A0999

Ambulance transportation HCPCS codes referenced for reimbursement

Bundled servicesmixedNot Covered

Ambulance Bundled Codes

Services not separately reimbursed when provided by same Ambulance Supplier on same date of service

ALS2 medication administrations — definition & criteria

CriteriaAt least three separate administrations of one or more medications by intravenous push/bolus or by continuous infusion (excluding crystalloid fluids)

Route requirementsMedication administrations must be IV push/bolus or continuous infusion; crystalloid fluids are excluded

Count definitionMust be three separate administrations (can be of one or more medications)

Provider Billing and Payment Rules

Billing Rule

Ambulance Supplier eligibility

Ambulance Supplier eligibility required for reimbursement. UnitedHealthcare considers only an Ambulance Supplier eligible for reimbursement of ambulance services reported with HCPCS codes A0021 and A0225-A0999. Non-Ambulance Supplier providers (for example, emergency room physicians) should report CPT and/or HCPCS codes that accurately describe services outside the A0021 and A0225-A0999 range. UnitedHealthcare will not reimburse non-Ambulance Suppliers for rendering ambulance services.

Denial Risk

Ambulance modifier requirement and denial risk

Valid two-character ambulance modifier is required. In alignment with CMS, UnitedHealthcare will reimburse ambulance transportation codes only when reported with a valid two-digit ambulance modifier from the Ambulance Modifiers list. Ambulance transportation services reported without a valid two-digit ambulance modifier will be denied. When the 'X' indicator (Intermediate stop at physician's office en route to the hospital) is used, 'X' must be the second digit and preceded by a valid origin digit; if 'X' appears as the first digit of the two-character modifier, the claim will be denied.

Denial Risk

Inpatient stay overlap payment rule

Ambulance transports overlapping an inpatient stay are not separately reimbursable. In alignment with CMS, ambulance services to/from an originating facility for diagnostic tests or specialty treatment (reported with modifiers HH, DH, or HD) that overlap the dates of an inpatient stay will not be reimbursed. The date-span exclusion does not include the date of admission or the date of discharge. These ambulance services should be paid by the originating facility and will not be paid separately by UnitedHealthcare.

Definitions and Terms

Same Ambulance Supplier — definition

DefinitionAmbulance Suppliers of the same specialty reporting the same Federal Tax Identification number (TIN).

ImplicationServices listed as bundled are not separately reimbursed when provided by the Same Ambulance Supplier on the same date of service.

ContextUsed to determine when multiple provider entities are treated as one billing entity for reimbursement rules.

Advanced Life Support, Level 2 (ALS2) — definition

Core definitionTransportation by ground ambulance vehicle with medically necessary supplies and services where either (1) at least three separate administrations of one or more medications by IV push/bolus or continuous infusion (excluding crystalloid fluids) OR (2) provision of at least one listed ALS2 procedure is met.

Examples of ALS2 proceduresManual defibrillation/cardioversion; Endotracheal intubation; Central venous line; Cardiac pacing; Chest decompression; Surgical airway; Intraosseous line.

Staffing standardALS vehicles must be staffed by at least two people, at least one certified as an EMT-Intermediate or EMT-Paramedic, per CMS.

Payment basisReimbursement is based on level of service provided, not on the vehicle used.