Pediatric Therapy CPT Code Reference
These are the CPT codes that drive revenue at pediatric therapy clinics running ABA, SLP, OT, and PT. Tracked by hand across locations, they leak. A modifier gets dropped, a unit cap is hit mid-month with nobody watching, or a prior auth lapses by a single session. Relay's AI employees watch code-level billing in real time so a human staff member catches the issue before it turns into a CO-197 or a write-off, working on top of the EHR stack you already run. CPT codes are owned and maintained by the American Medical Association, so the plain-English summaries here are Relay's own. You can source the official descriptors at ama-assn.org or the CMS fee schedule lookup.
Applied Behavior Analysis (ABA)
ABA billing is dense with modifier-sensitive codes and daily unit caps. One mismatched provider type or missed protocol modification note wipes out a full session's reimbursement.
A BCBA-conducted assessment that identifies the function of a patient's behavior and establishes the baseline for the treatment plan. Typically completed before any direct treatment begins.
Watch out: Requires prior auth at most payers before the first session. Submit the assessment report promptly; delays push back auth approval and stall the entire case. Units cap varies by payer, so confirm before scheduling follow-up assessments.
Direct skill-building or behavior-reduction work delivered by a behavior technician under BCBA supervision. Billed in 15-minute increments.
Watch out: Units per day limits are common. Supervision ratio requirements must be met and documented or payers will retract. Concurrent billing with 97155 on the same day requires careful time accounting.
The BCBA reviews data and adjusts the treatment protocol, either with or without the patient present. Billed in 15-minute increments.
Watch out: Often the first code cut in an audit. Document time and clinical rationale explicitly for each unit billed. Cannot be billed by a technician; it must be the supervising BCBA.
Training delivered to a parent or caregiver on how to carry out ABA strategies at home. The patient does not need to be present.
Watch out: Frequency limits apply at many payers. Caregiver identity and attendance must be documented. Coverage and frequency limits for caregiver guidance vary by payer, so verify the plan's policy before billing.
Group ABA treatment with protocol modification, delivered face-to-face to two or more patients by the physician or qualified health professional (the BCBA), not a behavior technician.
Watch out: Group size limits and supervision ratios differ by payer contract. Billing this when documentation does not clearly reflect a true group session is a common audit trigger.
Speech-Language Pathology
Speech codes live or die on documented medical necessity and accurate evaluation linkage. Without tight tracking, evaluations and treatment sessions frequently bill under the wrong code and get denied.
Individual speech, language, voice, communication, or fluency treatment. The most common billing code for routine SLP sessions.
Watch out: Requires GN modifier to indicate speech-language pathology services under a speech plan. Skipping GN is a top reason for CO-16 denials on SLP claims. Auth requirements under Medicare Advantage tightened September 1, 2024 (UnitedHealthcare outpatient SLP).
A comprehensive evaluation of both speech production (articulation, fluency) and language processing (comprehension, expression). Required to establish medical necessity before ongoing treatment.
Watch out: Many payers require this before authorizing 92507. If the initial eval is billed without prior auth in place, the resulting treatment authorizations can be delayed or denied retroactively.
Treatment targeting oral motor function, feeding behavior, or swallowing mechanics. Common in pediatric SLP caseloads where feeding difficulties co-occur with developmental diagnoses.
Watch out: Medical necessity documentation must directly link the feeding or swallowing deficit to a billable diagnosis. Some payers carve this out to a separate benefit or require a separate auth from standard SLP services.
Occupational Therapy
OT evaluation codes require the right complexity level or they downcode on audit. Shared codes like 97530 and 97535 get misattributed across disciplines when logged manually.
An occupational therapy evaluation for a patient with a focused presenting problem, limited review of history, and a brief clinical decision-making process.
Watch out: Complexity level selection must match documentation. Upcoding to 97166 or 97167 without supporting documentation is a common audit finding. GO modifier required for OT under a therapy plan.
An OT evaluation for a patient with an established history, multiple performance deficits, and a moderate level of clinical decision-making.
Watch out: Document the factors that justify moderate over low complexity explicitly. Payers reviewing for over-utilization will compare complexity distribution across your caseload.
Dynamic activities that use functional movement (lifting, reaching, carrying) to restore or build a functional skill. Billed in 15-minute increments.
Watch out: Must be distinct from 97110 (therapeutic exercise); the activity must have a direct functional goal, not just strength or range of motion. GO or GP modifier required depending on discipline. Frequent target for CO-50 (not medically necessary) denials when documentation is generic.
Direct training in activities of daily living such as dressing, grooming, meal prep, and home safety, typically under OT. Billed in 15-minute increments.
Watch out: GO modifier required for OT. Goals must be specific and functional, not vague. Often denied when documentation does not distinguish this from standard OT treatment already captured under another code.
Physical Therapy
PT codes are frequently underbilled because therapists document treatment time but miss billable manual therapy units. Every unbundled 97140 unit left off a claim is revenue that cannot be recovered.
A physical therapy evaluation for a patient with a stable presentation, limited comorbidities, and straightforward clinical decision-making.
Watch out: GP modifier required for PT under a therapy plan. Same complexity-matching risk as OT evals, so documentation must clearly support the level selected. Under-documenting can lead to downcoding on audit.
Hands-on techniques including joint mobilization, soft tissue work, and manual traction. PT and OT can bill this; requires direct therapist contact.
Watch out: Cannot be billed during the same time as other timed codes unless services are provided in separate time blocks. Concurrent billing with 97110 or 97530 is a frequent claim edit trigger. GP modifier for PT, GO for OT.
Common questions.
Do these CPT codes require prior authorization at most pediatric therapy payers?
Most do, especially for ABA (97151-97158) and SLP under Medicare Advantage plans. The authorization requirement varies by payer, plan, and code. A claim submitted without a required auth returns CO-197 regardless of how clean the clinical documentation is. Relay's AI employees track auth status per code and flag cases before the auth lapses or the session count runs out.
What modifiers are required on therapy claims?
Three discipline modifiers matter most here: GN (speech-language pathology under a speech plan), GO (occupational therapy under an OT plan), and GP (physical therapy under a PT plan). Missing or incorrect modifiers are the leading cause of CO-16 denials on outpatient therapy claims. ABA codes do not use these modifiers but have their own provider-type requirements.
What is the 2026 Medicare KX modifier threshold for therapy services?
The 2026 KX modifier threshold is $2,480 for combined PT and SLP services, and $2,480 separately for OT, per CMS and Noridian. Once a patient crosses the threshold, the KX modifier is required on each claim to indicate that services remain medically necessary. Missing KX above the threshold is an automatic denial.
How does Relay help with CPT code tracking across multiple locations?
Relay builds a custom AI employee that monitors billing data across all locations on your existing EHR stack (WebPT, CentralReach, SimplePractice, or others). It flags auth gaps, unit-cap proximity, missing modifiers, and denial patterns before they compound. A human staff member reviews and finalizes each action.
Stop tracking these by hand
Every code here is a place revenue slips when it is tracked by hand across locations. The free 30-minute intro call maps which ones an AI employee would catch before the claim goes out.