CurrentColorado Rocky Mountain Health PlansPolicy N/A

Outpatient therapy billing and modifier requirements (PT/OT/SLP)

Defines requirements for reporting outpatient physical therapy, occupational therapy, and speech-language pathology services (codes, revenue codes, and modifiers) for UB04/UB04-equivalent claims across products and networks.

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyOutpatient therapy billing and modifier requirements (PT/OT/SLP)

Policy CodePolicy N/A

Change TypeMinor revision

Effective DateN/A

Next Review DateOct 1, 2025

Key ActionSubmit the appropriate CPT/HCPCS code, the correct therapy revenue code (042x/043x/044x), and a single discipline modifier (GP/GO/GN) on UB04/equivalent claims.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

042x/043x/044xrequired therapy revenue code families

GN|GO|GPtherapy plan-of-care modifiers referenced

All productsapplies to

UB04claims form

One per linemodifier restriction

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Outpatient Therapy Coverage Criteria

Outpatient therapy billing and modifier criteria

Requirements for submitting therapy services under a plan of care:

All of the following must be met

Therapy services must be submitted with the appropriate CPT or HCPCS code for the services provided.
Therapy services must be submitted with the appropriate therapy revenue code (042x, 043x, or 044x).
Append exactly one discipline modifier (GN, GO, or GP) on the service line to indicate the plan-of-care discipline; only one therapy modifier per line is allowed.
Only one GN, GO, or GP modifier should be reported on the same service line.
Revenue code and modifier combinations must follow the discipline mapping: 042x lines may only contain GP; 043x lines may only contain GO; 044x lines may only contain GN.
Revenue code/modifier pairings are discipline-specific (e.g., 042x only with GP).
Discipline-specific evaluation and re-evaluation service codes must be reported with the modifier for the associated discipline (for example, PT evaluation codes reported with GP).
GN, GO, and GP modifiers refer only to services provided under a plan of care for PT, OT, and SLP and should not be used for other therapy services (e.g., respiratory or nutrition therapy).

Revenue Codes, Modifiers, and Code Lists

Therapy revenue codes and modifiersmixedCovered

042x	Physical therapy revenue code family
043x	Occupational therapy revenue code family
044x	Speech-language pathology revenue code family
GP	Modifier for services under a physical therapy plan of care
GO	Modifier for services under an occupational therapy plan of care
GN	Modifier for services under a speech-language pathology plan of care

Billing and Submission Requirements for Providers

Billing Rule

Billing requirements for outpatient therapy services — Submit appropriate CPT/HCPCS, applicable therapy revenue code (042x/043x/044x), and a single discipline modifier per line.

Submit appropriate CPT/HCPCS and the applicable therapy revenue code (042x/043x/044x). Report a single discipline modifier (GN/GO/GP) per line when services are provided under a certified therapy plan of care for PT/OT/SLP.

Therapy services must be submitted with the appropriate CPT or HCPCS code for the services provided.
Therapy services must be submitted with the appropriate therapy revenue code (042x, 043x, or 044x).
Submit only one discipline modifier (GN, GO, or GP) per service line when billing PT/OT/SLP under a certified plan of care.
Revenue code 042x (physical therapy) lines: only modifier GP is permitted.
Revenue code 043x (occupational therapy) lines: only modifier GO is permitted.
Revenue code 044x (speech-language pathology) lines: only modifier GN is permitted.
Discipline-specific evaluation and re-evaluation service codes must be reported with the modifier for the associated discipline (e.g., PT evaluation reported with GP).

Definitions and Modifier Descriptions

Always Therapy

DefinitionTherapy services performed by a qualified therapist under a certified plan of care.

Applies toOutpatient physical therapy, occupational therapy, and speech-language pathology services billed on UB04 or equivalent.

DocumentationService must be supported by a certified plan of care maintained in the medical record.

Sometimes Therapy

DefinitionTherapy service performed by a physician or non-physician practitioner outside of a certified therapy plan of care.

Provider typesMay be furnished by physicians or non-physician practitioners when not under a certified plan of care.