CurrentUnitedHealthcarePolicy 2025R5018A

Ambulance transportation billing and modifiers (UB04)

Reimbursement rules for ambulance services billed on UB04 or electronic equivalent, including required two-character origin/destination modifiers, applicable to institutional-based and supplier ambulance claims for UnitedHealthcare Commercial and Individual Exchange products.

Policy Summary

PayerUnitedHealthcare

PolicyAmbulance transportation billing and modifiers (UB04)

Policy CodePolicy 2025R5018A

Change TypeNo material change

Effective Date

Next Review Date

Key ActionReport a valid two-character origin/destination ambulance modifier with each ambulance HCPCS code; institutional providers must also report QM or QN when applicable.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

A0425-A0436Ambulance HCPCS codes discussed

two-digitModifier length

0540/0545Required revenue codes

QM or QNInstitutional modifier

Reimbursement Criteria for Ambulance Transports

Reimbursement criteria for ambulance transports

Reimbursement is allowed when ambulance HCPCS codes are reported in accordance with the modifier and billing rules below.

Ambulance HCPCS code must be reported with a valid two-character origin/destination modifier (alpha characters) to be reimbursed.

Institutional-based providers must append modifier QM (arranged) or QN (direct) with the HCPCS code.

When 'X' is used to indicate an intermediate physician office stop en route to the hospital, 'X' must appear in the second (destination) position of the two-character modifier; if 'X' appears in the first position the ambulance transportation code will be denied.

Ambulance service and mileage must be reported on separate claim lines with the same date of service and on the same claim using the appropriate revenue code (0540 or 0545). The ambulance service line should be reported with one unit; mileage units should reflect the loaded number of miles being billed.

Policy Summary

PayerUnitedHealthcare

PolicyAmbulance transportation billing and modifiers (UB04)

Policy CodePolicy 2025R5018A

Change TypeNo material change

Effective Date

Next Review Date

Key ActionReport a valid two-character origin/destination ambulance modifier with each ambulance HCPCS code; institutional providers must also report QM or QN when applicable.

SourceLink

On This Page

Ambulance Codes, Modifiers, and Service Units

Covered HCPCS CodesHCPCSCovered

A0425	Ground mileage, per statute mile
A0426	Ambulance service, basic life support, non-emergency transport, level 1
A0427	Ambulance service, basic life support, emergency transport, level 2
A0428	Ambulance service, basic life support, non-emergency, renal dialysis transports
A0429	Ambulance service, advanced life support, non-emergency, level 1
A0430	Ambulance service, advanced life support, emergency, level 2
A0431	Ambulance service, specialty care transport (SCT), level 1
A0432	Ambulance service, specialty care transport (SCT), level 2
A0433	Advanced life support, non-emergency, level 3
A0434	Advanced life support, non-emergency, level 4

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Covered Modifier CodesModifierCovered

AA	Origin/Destination two-character alpha modifier format — first character = origin, second = destination (CMS-based)
D	Diagnostic or therapeutic site other than P or H when these are used as origin codes (single alpha character for origin/destination position)
E	Residential, domiciliary, custodial facility (other than 1819 facility)
G	Hospital based ESRD facility (used as origin or destination within two-character ambulance modifier)
H	Hospital
I	Site of transfer (e.g., airport or helicopter pad) between modes of ambulance transport
J	Freestanding ESRD facility (used as origin or destination within two-character ambulance modifier)
N	Skilled nursing facility
P	Physician's office
R	Residence

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Ambulance service units

Service reportingReport each ambulance service with the appropriate HCPCS code and a single unit for the ambulance service line. Use revenue code 0540 or 0545 when appropriate.

Mileage reportingReport mileage on a separate service line with HCPCS A0425 (ground mileage) and the number of units equal to the loaded number of miles billed.

Modifier formatUse a two-character alpha modifier where the first character denotes origin and the second denotes destination (example: RH = Residence to Hospital). Each character is a single alpha character from the CMS-designated list (D, E, G, H, I, J, N, P, R, S, X).

Claims Submission and Billing Rules

Billing Rule

Claims submission requirements

Report a valid two-character origin/destination ambulance modifier (two single-character alpha digits) with each ambulance HCPCS code. Institutional-based providers must also append modifier QM (services provided under arrangement) or QN (services provided directly). Report ambulance service and mileage on separate claim lines with the appropriate revenue code (0540 or 0545); report service line with one unit and mileage units equal to loaded miles.

Each ambulance HCPCS code must include a two-character origin/destination modifier (alpha characters).
Institutional providers must report QM or QN with the HCPCS code.
Ambulance service and mileage must be on separate lines with revenue code 0540 or 0545; service = one unit; mileage units = loaded miles.

Denial Risk

Modifier position rule for 'X'

If the 'X' destination code (intermediate stop at a physician's office en route to hospital) is used it must appear in the second position of the two-character modifier and be preceded by a valid origin code; if 'X' is used in the first position the claim will be denied.

'X' is a destination code only and must be in the second digit position.
'X' in the first digit position will result in denial of the ambulance transportation code.

Billing Rule

Bundling of supplies

Supplies are considered included in the ambulance service base rate and must not be billed separately in addition to the ambulance service HCPCS code.

Do not submit separate charges for supplies in addition to the ambulance HCPCS code.

Provider and Supplier Definitions

Provider

Definition'Provider' refers to a hospital‑based ambulance provider (institutional-based).

Modifier responsibilityInstitutional providers must report an origin and destination two-character alpha modifier with each ambulance HCPCS code per CMS guidelines.

Institutional-specific modifiersInstitutional providers may also be required to append QM (arranged) or QN (direct) per billing guidance (see policy).

Supplier

Definition'Supplier' is any ambulance service that is not institutionally based (non–hospital-based).

Modifier responsibilitySuppliers must report an origin and destination two-character alpha modifier with each ambulance HCPCS code per CMS guidelines.

DistinctionTerm differentiates non‑institutional ambulance services from hospital‑based (provider) ambulance services for billing rules.