ABA Therapy Billing Guidelines: Prevent Authorization and Unit Denials

ABA therapy billing guidelines come down to four checks on every claim. First, pick the adaptive behavior CPT code that matches who delivered the service. Then count units with the CPT time rule, confirm an active prior authorization for that code, and list a rendering provider the payer accepts. Also, plan now for January 1, 2027, when the code set changes and codes 0362T and 0373T stop being valid.

ABA Therapy Billing Guidelines at a Glance

These rules come from the ABA Coding Coalition, the Behavior Analyst Certification Board (BACB) and published payer manuals. Even so, your payer contract and state Medicaid manual decide the final answer.

ABA CPT Codes for 2026 Dates of Service

The AMA lists ABA services as adaptive behavior services. Through December 31, 2026, payers that follow CPT use the ten codes below. The descriptions are short summaries, not the official CPT wording.

Code	Service (summary)	Who delivers it
97151	Assessment and treatment planning, including face-to-face testing plus scoring, analysis and report writing	QHP
97152	Supporting assessment that follows a QHP protocol	Technician
97153	One-to-one treatment by protocol	Technician
97154	Group treatment by protocol for two or more patients	Technician
97155	Treatment with protocol modification, including direction of a technician	QHP
97156	Family treatment guidance for one patient, with or without the patient	QHP
97157	Multiple-family group guidance without patients present	QHP
97158	Group treatment with protocol modification	QHP
0362T	Supporting assessment of destructive behavior by two or more technicians, with the QHP on site	Technicians
0373T	Treatment of destructive behavior by two or more technicians, with the QHP on site	Technicians

Who counts as a QHP? The AMA ties the term to education, training, licensure and scope of practice. The Coalition lists licensed behavior analysts, BCBAs, BCBA-Ds and other licensed professionals with behavior analysis in their scope. Still, state law and payer policy decide who qualifies.

How to Count ABA Billing Units

All of these codes use 15-minute units. Under the CPT time rule, you earn a unit once you pass the midpoint. So 8 to 22 minutes equals one unit, while less than 8 minutes is not reportable, according to the ABA Coding Coalition.

For example, a 97153 session from 2:00 to 4:50 p.m. lasts 170 minutes. That equals 11 full units plus 5 extra minutes. Because 5 minutes is under the midpoint, you bill 11 units.

This rule differs from the Medicare 8-minute rule for therapy, which adds minutes across several timed codes. Payers may also cap daily units. For instance, the Coalition notes a Medicare edit of 8 units per day for 97151.

What Changes for ABA Billing on January 1, 2027

The AMA approved a major ABA code update for 2027. According to the ABA Coding Coalition billing codes page, the new set takes effect January 1, 2027. The Coalition also warns that 0362T and 0373T have no grace period, so they become invalid for dates of service on or after that day.

2027 code	What it covers (summary)	Replaces or changes
97148	Supporting assessment of harmful behavior by two technicians in a customized setting	Replaces 0362T
+97149	Add-on for each extra technician, up to five in total, during 97148	Captures extra technician time
97159	Treatment of harmful behavior by two technicians in a customized setting	Replaces 0373T
+97160	Add-on for each extra technician, up to five in total, during 97159	Captures extra technician time
97173	One-to-one QHP treatment with analysis	Takes over QHP direct treatment from 97155
97180	QHP non-face-to-face work, such as data review, protocol decisions, discharge planning and patient-specific technician training	New; most of this work had no separate code before

Revised Codes You Already Use

• 97155: It now covers only QHP direction of a technician with analysis. Therefore, it always pairs with a technician code.
• 97156, 97157 and 97158: All three now include analysis, which replaces protocol modification in 97158. The analysis does not require a protocol change, but the note must show it.
• Group size: The old limit of eight patients is gone. However, payers may keep their own limits.
• 97151 and 97180: You cannot report both for the same patient on the same day.

How to Report 97180

First, add up all 97180 time for a seven-day period, such as Sunday to Saturday. Then report the total units on one claim line. However, each date of work still needs its own note. Writing session notes, quality assurance and general staff training do not count.

Update authorizations before January 1, 2027. A 2026 approval that lists 0362T, 0373T or 97155 for direct QHP treatment will not match 2027 claims. So ask each payer how it will handle open authorizations and when it will load the new codes.

Who Can Render Each ABA Service

Most ABA claim edits depend on who delivered the minutes. Technicians deliver 97152, 97153 and 97154. Meanwhile, QHPs deliver assessment, direction, family guidance and QHP-led group codes.

RBT Supervision Is a Certification Duty, Not a Code

The BACB treats the Registered Behavior Technician (RBT) as a paraprofessional who works under close, ongoing supervision. Its RBT Handbook requires supervision for at least 5% of service hours each month, with at least two real-time contacts.

However, that supervision does not create a claim. The Coalition states that CPT has no stand-alone code for supervising technicians without the patient. Instead, 97155 covers active direction while the patient is in session. Starting in 2027, 97180 adds patient-specific technician training, but general training still falls outside it.

Rendering Provider and Modifier Rules

Payers also differ on how a claim shows the clinician. TRICARE, for example, requires the rendering provider name and NPI on every claim. It also requires a taxonomy code for each provider type, including technicians and assistant behavior analysts.

Many Medicaid and behavioral health plans add education-level modifiers, such as HM for less than a bachelor degree, HN for bachelor level and HO for master level. Some states also define U modifiers. Because each manual sets its own meaning, confirm the modifier before you submit.

In addition, a QHP who simply fills in for an absent technician reports 97153, and some payers want a modifier for that. Enrollment gaps cause similar denials, so keep provider credentialing current for every clinician.

Prior Authorization Rules for ABA Therapy

Payers such as TRICARE and state Medicaid programs often require approval before ABA starts. An approval usually lists codes, units and dates. As a result, any claim outside those limits can deny even when the coding is right.

Step 1: Verify Benefits Before the First Session

• Check eligibility, ABA coverage and diagnosis rules.
• Confirm referral rules, covered codes, settings and telehealth limits.
• Recheck coverage when the patient changes plans, because an approval does not move to a new payer.

For Medicaid patients under 21, CMS has said states must cover medically necessary autism services under the EPSDT benefit. For more front-end steps, see our guide to preventing insurance verification errors.

Step 2: Record Every Authorization Detail

Field	Why it matters
Authorization number	Links each claim to the approval
Start and end dates	Services outside the range deny
Approved codes	A 97153 approval does not cover 97155
Units per code and period	Weekly or monthly caps may also apply
Rendering provider or setting	Some approvals restrict both
Renewal deadline	Sets your reauthorization calendar

Step 3: Start Reauthorization Early

Payer timelines vary, so build your calendar from each manual. TRICARE offers a useful benchmark. Under the TRICARE Operations Manual, autism care authorizations run six months. Providers should request the next one no earlier than 60 days and no later than 30 days before expiration.

TRICARE also needs updated outcome measures before it issues the next approval. Meanwhile, a late request puts services at risk of nonpayment until the new approval arrives. Therefore, confirm approval before treatment continues into a new period.

ABA Hour Utilization Tracking

Utilization tracking compares approved units with used and scheduled units. Without it, clinics deliver care that the authorization no longer covers. The math is simple: remaining units equal approved units minus used units, and remaining hours equal remaining units divided by 4.

Hypothetical 97153 authorization	Units	Hours
Approved for the period	480	120
Used to date	320	80
Remaining	160	40
Still scheduled (12 hours a week for 4 weeks)	192	48
Projected shortfall	32	8

In this example, the schedule exceeds the balance by 32 units. So the team should adjust the schedule or request more units before the fourth week.

Track Five Unit Counts

• Authorized: Approved units for each code.
• Rendered: Delivered and documented units.
• Billed: Units already on claims.
• Scheduled: Future sessions on the calendar.
• Remaining: Approved units not yet used.

Billed units alone can mislead, since finished sessions may not be on a claim yet. Also watch daily and weekly caps. For instance, TRICARE denies 97153 units above 32 per day or 160 per week.

Concurrent Billing Rules for ABA Therapy

Concurrent billing means two services for the same patient overlap in time. CPT guidance allows some overlaps, yet payers can still refuse them. Compare both sources before you bill.

Code pair	ABA Coding Coalition guidance	TRICARE rule
97153 with 97155	Allowed with two different people; one QHP cannot report both	Not allowed; pays the higher rate and denies the other
97154 with 97158	Not allowed, because 97158 is only for QHP-led groups	Not applicable; 97154 is not on the ACD code list
97153 with 97156	Allowed when caregivers meet the QHP apart from the patient session	Allowed when the patient is not in the family session

Starting in 2027, 97155 always pairs with a technician code. As a result, overlap with 97153 becomes the normal pattern, which makes each payer rule more important.

Document overlaps line by line. Record exact start and stop times for each provider, show whether the patient was present, and describe what the QHP directed or analyzed. TRICARE also requires each session on its own claim line.

Documentation That Supports ABA Claims

• 97153: Technician name and credential, exact times, protocols run, and patient data.
• 97155: What the QHP observed or directed, the analysis, and any change. If nothing changed, say why.
• 97151: The assessment work done on each date, both face-to-face and non-face-to-face.
• 97173 and 97180 (2027): The analysis during QHP treatment, and the date, time and task for each piece of 97180 work.
• Every note: Signatures and any identifiers the payer requires.

Templates help, but cloned notes invite audits. So each note should describe what happened in that session.

Common ABA Claim Denials and How to Prevent Them

Problem	What the payer sees	Prevention
Expired authorization	Dates outside the approval	Calendar renewals 60 days ahead
Units over the approval	Overrun on a code or period	Reconcile units weekly
Code not on the approval	For example, 97155 under a 97153-only approval	Match codes to the approval
Wrong rendering provider	Unenrolled clinician or missing modifier	Verify enrollment and modifiers
Unsupported 97155	No direction or analysis in the note	Record the QHP clinical work
Barred overlap	Payer rejects the code pair	Check concurrency policy first
Deleted code in 2027	0362T or 0373T on 2027 dates	Switch to 97148, 97149, 97159 or 97160

When a denial arrives, read the remittance codes first. Then choose a corrected claim, a reconsideration or an appeal. If denials keep repeating, our denial management services can trace the root cause.

Frequently Asked Questions