ABA CPT Codes: The 2026 Billing Guide and Every Confirmed 2027 Change

ABA CPT codes are the Adaptive Behavior Services codes the American Medical Association maintains for applied behavior analysis. Ten codes are active in 2026: Category I codes 97151 to 97158, plus Category III codes 0362T and 0373T. All ten are timed, billed in 15-minute units, and tied to who rendered the service.

On July 14, 2026, CMS published the proposed 2027 descriptors inside the Medicare Physician Fee Schedule proposed rule. This page carries all of them, including the six new codes, with the caveat that final numbers won't publish until late 2026.

What you'll find here that most guides skip: unit rules that change by contract, the published MUE values, payer-specific caps with real numbers, and the full 2027 restructure.

ABA CPT Codes 2026: Complete Reference Table

The ABA CPT codes 2026 set holds ten codes. Eight Category I, two Category III, all timed in 15-minute units. Every descriptor below matches the AMA-approved wording published by the ABA Coding Coalition billing codes page, abbreviated here for width. Full verbatim descriptors appear in the sections that follow.

Table caption: ABA CPT Codes 2026: Complete Reference

Picking the code is only half the claim. The rendering provider's credential is the other half, and mismatching those two is the most common preventable ABA denial we see. That's where the next section starts.

Who Renders and Who Bills: The Split That Drives Most ABA Denials

Three codes belong to the technician. Codes 97152, 97153, and 97154 are rendered by a behavior technician, usually an RBT, working under the direction of the QHP. Five belong to the QHP: 97151, 97155, 97156, 97157, and 97158.

Submit a technician code with a QHP as the rendering provider, or the reverse, and the claim denies before anyone reads the clinical note. Catching that mismatch pre-submission is basic outsourced medical billing services work, and it's the single cheapest denial to prevent.

What "Qualified Healthcare Professional" Actually Means

The AMA defines it this way:

"A 'physician or other qualified health care professional' is an individual who is qualified by education, training, licensure/regulation (when applicable) and facility privileging (when applicable) who performs a professional service within his/her scope of practice and independently reports that professional service."

Almost nobody states the operational consequence. The BACB is a certification body, not a licensure board. Whether a certificant counts as a QHP for reporting these codes gets decided by state licensure law and each payer's provider-type list, not by the certification alone. The AMA and CMS definition of QHP is the starting point, not the answer.

BCaBA handling varies more than most people expect. Some payers credential them independently. Others require them to bill under the supervising BCBA, and a few now allow them into codes that used to be RBT-only. Indiana opened 97153 to BCaBAs and BCBAs in April 2026, using U-modifiers to separate the tiers.

Why Credentialing Decides Whether the Code Even Matters

Codes 97155 through 97158 require QHP-level rendering. If that BCBA isn't credentialed and contracted with the payer, the claim dies at the provider-enrollment edit and the code never gets evaluated. Coding the session perfectly doesn't help you.

Run the math on a gap. A BCBA billing roughly $60 to $80 per hour across five to six clients daily generates something like $15,000 to $20,000 a month. A 90-day enrollment delay is $45,000 to $60,000 you can't recover.

Why you can't recover it: claims for dates before the effective enrollment date aren't appealable. Our ABA credentialing requirements breakdown covers the documentation that stalls those applications.

Getting a BCBA enrolled shouldn't take three months. MedSole RCM handles ABA provider credentialing at $99 per payer, with enrollment typically completed in 30 to 45 days.

Table caption: Who renders each ABA CPT code

None of this is payer preference. Every OIG state audit of Medicaid ABA published so far has flagged services rendered by staff without required credentials or supervision among its top findings. In Indiana, 97 of 100 sampled enrollee-months included services delivered by staff who lacked appropriate credentials. That's a federal audit finding, not a contract quirk.

ABA Assessment Codes: 97151, 97152, and 0362T

Three of the ABA CPT codes cover assessment. One carries an error that's circulated for years, and one carries an error that Google's own AI Overview repeats today.

CPT 97151, Behavior Identification Assessment

The verbatim 97151 CPT code description reads:

"Behavior identification assessment, administered by a physician or other qualified health care professional, each 15 minutes of the physician's or other qualified health care professional's time face-to-face with patient and/or guardian(s)/caregiver(s) administering assessments and discussing findings and recommendations, and non-face-to-face analyzing past data, scoring/interpreting the assessment, and preparing the report/treatment plan"

Read that last clause again. 97151 is the only ABA code that permits billing non-face-to-face time. Scoring, interpreting, reviewing records, and writing the treatment plan all count. A session with 45 minutes face-to-face plus 90 minutes of scoring and plan writing totals 135 minutes, which is nine units.

The QHP has to perform both halves. The Coalition is explicit that you can't report 97151 for face-to-face work alone or indirect work alone, and you can't use it for day-to-day treatment planning. Day-to-day planning is bundled into the treatment codes.

Some sources describe 97151 as requiring "30 minutes or more" of face-to-face time. That's wrong. It's a 15-minute timed code, and at least one widely circulated billing guide states the 30-minute figure while contradicting itself in its own table two paragraphs later. Your medical coding audit process should catch that kind of internal inconsistency before it reaches a claim.

MUE reality matters here more than on any other code. The Medicaid MUE for 97151 sits at 32 units per day. The Medicare MUE sits at 8. Section 10 covers why that gap exists and what it costs you.

CPT 97152, Behavior Identification Supporting Assessment

The 97152 CPT code description:

"Behavior identification supporting assessment, administered by one technician under the direction of a physician or other qualified health care professional, face-to-face with the patient, each 15 minutes"

Technician-rendered, face-to-face only, no indirect time. Two errors circulate about this code and both cause real problems. One popular guide describes 97152 as covering assessment "and treatment." It doesn't; it's assessment only. Another describes it as involving "destructive behavior." It doesn't; destructive behavior is the 0362T criterion.

Note what the descriptor says about independence. Technicians don't perform assessments on their own under 97152. The QHP determines which supplemental assessments are needed, reviews the procedures with the technician, and has the technician practice recording data. That prep work is bundled into 97152 and isn't separately reportable.

Billing 97152 standalone, with no 97151 assessment on the same or adjacent dates, is a common denial trigger.

CPT 0362T and the Retired Descriptor Still Circulating

The current 0362T descriptor requires four components, and all four must be met:

• Administered by the physician or other QHP who is on site
• With the assistance of two or more technicians
• For a patient who exhibits destructive behavior
• Completed in an environment that is customized to the patient's behavior

"On site" has a specific meaning: the QHP is immediately available and interruptible. They can't be delivering direct services to another client at the same time, because they couldn't leave that session to help. They can be directing a technician under 97155, since that's interruptible.

You'll still see 0362T described as an "exposure behavioral follow-up assessment." That's the retired 2014 Category III language. It was replaced on January 1, 2019 with "behavior identification supporting assessment," and Google's AI Overview currently repeats the old wording. Check the current ABA Coding Coalition billing codes page before trusting any secondary source on this one.

One more constraint people miss: 0362T can't be reported when a second technician steps in on an impromptu basis. These services need preauthorization for cases where all four criteria are met from the start.

The 0373T CPT code description mirrors 0362T word for word, swapping "adaptive behavior treatment with protocol modification" for the assessment language. One quirk decides the units: report only one technician's total time, not each technician's. A three-hour session with three technicians is 12 units of 0373T, not 36.

Both T-codes are deleted effective January 1, 2027. The 2027 overhaul section covers what replaces them.

ABA Treatment Codes: 97153, 97154, and 97158

Direct treatment is where the volume lives. Three of the ten ABA CPT codes handle it. These aba therapy cpt codes account for most claim lines in a typical practice, and 97153 alone usually carries the majority.

CPT 97153, Adaptive Behavior Treatment by Protocol

The 97153 cpt code is the direct one-to-one treatment a technician delivers by following the protocol the BCBA wrote. Verbatim:

"Adaptive behavior treatment by protocol, administered by technician under the direction of a physician or other qualified health care professional, face-to-face with one patient, each 15 minutes"

Document these seven things every session:

• Start and stop times
• Unit count
• Programs and goals addressed
• Data collected
• Client response
• Technician name and credential
• Barriers that affected delivery

Notes and codes have to match before submission, which is the whole point of a clean claim submission process. Auditors read the note, not the claim.

The distinction that generates denials: 97153 is protocol delivery. The moment the QHP modifies the protocol in real time, that portion becomes 97155. When a QHP simply steps in and delivers the existing protocol without modifying it, the Coalition says to report 97153 with a modifier showing the higher credential level.

Caps on the 97153 cpt code vary widely. The Medicare and Medicaid MUE both sit at 32 units per day. Individual payers go lower, and some go a lot lower. Nevada Medicaid limits all ABA services to 15 to 25 hours per week under a focused model and 25 to 40 under a comprehensive model.

CPT 97154, Group Adaptive Behavior Treatment

"Group adaptive behavior treatment by protocol, administered by technician under the direction of a physician or other qualified health care professional, face-to-face with two or more patients, each 15 minutes"

The descriptor says "two or more." Several guides state the ceiling is eight and attribute it to the AMA, which isn't quite right either way.

That eight-patient limit comes from the Coalition's supplemental guidance, which defines a group as at least two patients and no more than eight. Authoritative, but not descriptor language. Some payers set their ceiling lower.

Bill 97154 once per patient attending, not once per session. Documentation has to show individualized goals and discrete data for each patient present. Group claims fail on review when the note describes the group instead of the child.

CPT 97158, Group Treatment with Protocol Modification

"Group adaptive behavior treatment with protocol modification, administered by physician or other qualified health care professional face-to-face with multiple patients, each 15 minutes"

Most guides get this one backwards. They treat "protocol modification" as a requirement, then conclude that 97158 is rarely billable because most group sessions are protocol delivery. The Coalition says the opposite: report 97158 any time a behavior analyst leads a treatment session with two to eight patients. Modification may happen, but it isn't required.

The real line between 97154 and 97158 is who leads the session. Technician-led groups are 97154. QHP-led groups are 97158. You can't report both concurrently for the same session, since 97158 is meant for QHP-led groups only.

In 2027, 97158's descriptor drops "with protocol modification" and becomes "group adaptive behavior treatment with analysis." Section 15 has the full language.

CPT 97153 vs 97155: The Comparison That Changes in 2027

No comparison in ABA billing gets searched more, and every guide covers it. Almost none of them mention that the comparison stops working in about 16 months.

CPT 97155, Adaptive Behavior Treatment with Protocol Modification

The current 97155 cpt code description:

"Adaptive behavior treatment with protocol modification administered by physician or other qualified health care professional, which may include simultaneous direction of technician, face-to-face with one patient, each 15 minutes"

Report it in two situations. The QHP conducts one-to-one treatment to observe behavior change or troubleshoot protocols. Or the QHP joins the technician and patient mid-session to direct implementation of a new or modified protocol.

Downcoding happens when the note describes observation. Show what the QHP considered, what changed, why it changed, and how the client responded.

The Coalition addresses the case that trips people up. If the QHP observes and decides the protocol doesn't need modification, that still supports the code, as long as the note lists the components considered and the reasoning for leaving them alone. Writing "observed technician implementing protocol" doesn't support 97155.

Can 97153 and 97155 Be Billed Concurrently

Three separate layers govern this, and conflating them is why the answer looks contradictory across the internet.

1. CPT intent permits it. The Coalition concurrent billing guidance states that 97153 and 97155 may be reported concurrently as long as the criteria in both descriptors are met. One hard limit applies: a single QHP can't report both codes concurrently. Two different people have to render the two services.

1. Payer policy varies. Plenty of payers restrict or deny concurrent billing regardless of CPT intent. Some pay the higher-rate code and deny the other outright. Verify by contract, not by coding guide.

1. TRICARE prohibits it. The Autism Care Demonstration excludes concurrent billing across the Category I adaptive behavior codes, with a narrow exception where the family and beneficiary receive separate services and the beneficiary isn't present.

Bing Copilot currently answers this by asserting that "many payers do not allow 97155 and 97153 at the same time" as though it were a coding rule. It's a payer policy pattern, and the difference decides whether your appeal has a basis.

Table caption: CPT 97153 vs 97155, what changes and when

Mark your calendar for January 1, 2027. On that date 97155 drops "protocol modification" and becomes "adaptive behavior direction of technician and analysis." A new code, currently placeholdered as 97X6X, takes over QHP direct treatment. Every 97153-versus-97155 article on the internet becomes obsolete, including the accurate ones. These aba cpt codes are about to mean different things.

ABA Caregiver Training Codes: 97156 and 97157

No pair in the code set gets misdescribed more often. Multiple published guides call both codes "family adaptive behavior treatment with protocol modification." The descriptors say guidance.

It gets worse from there. One guide describes 97157 as group treatment for multiple patients, when the patient is never present. Another has 97156 as one-to-one individual therapy. These aba therapy cpt codes are worth getting right, because caregiver training now carries authorization minimums in a growing number of states.

CPT 97156, Family Adaptive Behavior Treatment Guidance

The 97156 cpt code description:

"Family adaptive behavior treatment guidance, administered by physician or other qualified health care professional (with or without the patient present), face-to-face with guardian(s)/caregiver(s), each 15 minutes"

Training, not updating. That single distinction decides payment on more 97156 claims than anything else. A session where the BCBA reviews progress or walks a parent through data generally doesn't support the code. A session where the caregiver gets taught, coached, or shown a strategy does.

Document the training objectives, the techniques taught, the strategies demonstrated, caregiver participation, any role-play or modeling performed, competency observed, and next training goals.

Who counts as a caregiver depends on payer policy. Immediate family is almost always covered. Some payers extend it to babysitters, teachers, or daycare providers, and some don't.

The 2027 revision fixes the ambiguity directly. The proposed descriptor adds explicit language covering "discussing protocols and treatment targets and/or training the caregiver(s) to implement assessment or treatment protocols with the patient." The work that's been getting denied becomes descriptor language.

CPT 97157, Multiple-Family Group Guidance

"Multiple-family group adaptive behavior treatment guidance, administered by a physician or other qualified healthcare professional (without the patient present), face-to-face with multiple sets of guardians/caregivers, every 15 minutes"

Two things separate 97157 from 97156. Multiple families instead of one, and the patient is never present. That absence is a descriptor requirement, not a scheduling preference.

Report it once per set of caregivers for a given patient. Five sets of parents in the room means five reports, one per patient, not one report for the session.

97157 isn't group treatment. Patients aren't in the room. Any source describing it as multi-patient group intervention is describing 97154 or 97158.

Why Every Source Groups ABA Codes Differently

Read more than one guide and you've seen the ten ABA CPT codes grouped at least three different ways. Some sources call them aba codes, some call them adaptive behavior services, and the buckets shift with the label. That isn't sloppiness. Different sources group by different logic, and the grouping your payer uses is the one that governs your claim.

Table caption: How different sources group the ABA CPT code set

Only one of those is authoritative. The AMA's two-group structure is the structure in the code book: Adaptive Behavior Assessment and Adaptive Behavior Treatment, each split into Category I and Category III. Everything else is a teaching aid or a payer's internal filing system.

The grouping that decides whether you get paid is a third thing. Payers don't adjudicate on the word "ABA," and they don't care which bucket a guide assigned. They adjudicate on five variables: the code itself, the rendering provider's type and credential, the place of service and telehealth status, prior authorization, and correct-coding overlap rules.

When a payer's provider manual groups the aba billing codes differently from the AMA, follow the payer's grouping for that payer's claims and the AMA's descriptors for what each code means. Those are two separate questions, and mixing them up is how practices end up arguing the wrong point on appeal.

How ABA Units Actually Work: Two Rules That Agree and the Contracts That Override Them

Ask three billers how many units a 23-minute session generates and you may get two answers. Working coders argue about this on public forums. The disagreement survives because most guides describe the rules incorrectly, and because a handful of payers have tried to impose minimums that contradict both of the real rules.

The part that resolves it: the AMA rule and the Medicare rule produce the same answer for every ABA code. They agree. Which unit rule applies is a contract question, not a coding question.

The AMA Midpoint Rule

CPT reports a unit of a time-based code once the midpoint of the time increment has passed. All ten adaptive behavior codes are 15-minute codes, so the midpoint is 7.5 minutes and the practical threshold is 8.

The Coalition states it plainly: work lasting 8 to 22 minutes is reportable as one unit, and work lasting less than 8 minutes isn't reportable at all.

The Medicare 8-Minute Rule

The 8-minute rule governs Part B outpatient therapy furnished under a plan of care. It's a Medicare payment policy, not a CPT convention, and Medicare doesn't cover ABA.

So it reaches adaptive behavior services only where a commercial payer or state Medicaid program adopted it by contract. Many have. Our breakdown of the 8-minute rule in therapy billing covers the mechanics.

The Medicare methodology, labeled as such:

Compare that to the midpoint rule and the answer lines up. Under both, 23 minutes is two units. Any guide claiming these two rules disagree for ABA hasn't checked.

Where the Answer Actually Changes

Payer contracts are the variable. Some state Medicaid programs and commercial carve-outs require the full 15 minutes with no rounding, which makes 23 minutes one unit and strands the remaining eight. Others have tried to set their own minimum and lost when challenged.

Optum proposed requiring 10 minutes per unit for 2020 and rescinded it after the Coalition pointed out that the policy contradicted both AMA and CMS guidance. Louisiana Medicaid did the same thing and reversed it. Both agreed to follow the midpoint rule.

One more variable almost nobody publishes: some payers calculate units per code, and others let you aggregate minutes across time-based codes for the date of service. Same session, same minutes, different unit count.

Find the answer in your provider manual, and document actual start and stop times either way, because every approach requires them.

Rounding wrong for six months creates a repayment liability sitting quietly in your AR. Time-calculation errors show up as a named finding in every OIG state audit of Medicaid ABA published so far.

Correct-coding policy updates quarterly through the CMS Medicaid NCCI program. A rule you verified two years ago deserves a second look. Most aba billing guidelines you'll find online don't carry a review date at all.

If nobody at your practice can name which unit rule each payer contract uses, that's the gap. MedSole RCM's denial management services start with a free denial pattern review.

MUE Limits on ABA CPT Codes

An MUE is a unit-of-service limit under the National Correct Coding Initiative, published quarterly by CMS. It states the maximum units of a code CMS considers typical for one patient on one date of service. Claims above it get flagged or denied, usually with CARC CO-151. MUEs aren't always hard caps, and that distinction is where recoverable revenue sits.

The Two-Table Problem

CMS publishes two separate MUE files each quarter, one for Medicare and one for Medicaid, and the values differ by code. Many providers don't know the tables are separate, and some payers adjudicate against the wrong one.

Table caption: MUE values for ABA CPT codes, Medicare vs Medicaid

Values as published by the ABA Coding Coalition. Verify the current quarterly file before relying on any of them.

97151 is the clearest example of the gap. A full-day assessment billing 20 units clears the Medicaid table and auto-denies against the Medicare table. Most ABA patients are Medicaid beneficiaries, which is why the Coalition urges payers to adopt the Medicaid values. Many payers adopt the Medicare values instead, partly because CMS publishes only the Medicare MUEs on its website.

The values are contested, not settled. The Coalition asked CMS to align the Medicare MUE for 97151 with the Medicaid value and to raise the MUEs for 97154 and 97155. CMS declined pending more utilization data. You can follow that thread on the Coalition MUE advocacy record.

When ABA Units Exceed the MUE

A child in intensive services can legitimately exceed these thresholds. Eight hours of technician treatment, BCBA supervision time, and a caregiver training session on one date is a normal clinical picture and an abnormal claim.

MUEs represent an upper limit that requires supporting documentation, not an absolute prohibition. Appeals need the clinical rationale and evidence that the units above the threshold were medically necessary for that specific patient. Our CO-197 prior authorization denials guide covers the documentation pattern that survives review.

Be realistic about the odds. A peer-reviewed MUE analysis published in Behavior Analysis in Practice examined MUE misuse as a driver of improper ABA denials.

Its finding is uncomfortable. In an informal review of one national provider's data covering hundreds of appeals across multiple payers, no claims were paid on appeal. The provider had submitted uncontested evidence that the services were delivered, correctly coded, and medically necessary.

Prevention beats appeal. Pull the current quarterly file for the correct table, learn your payer's own cap, and build the medical-necessity documentation into the authorization request rather than the appeal letter. The CMS Medically Unlikely Edits page publishes the Medicare file each quarter.

ABA Modifiers: What Each One Tells the Payer

Modifiers tell the payer who rendered the service and how it was delivered. In ABA they carry unusual weight, because the same aba cpt codes can be delivered by three different credential levels. Requirements vary by state, by payer, and sometimes by place of service.

Provider-Level Modifiers

Table caption: Common ABA billing modifiers by provider level

U-modifiers have no national meaning. A U3 in one state program means something completely different in another. Indiana, for example, uses U2 for BCaBA-delivered 97153 and U3 for BCBA-delivered 97153. Never carry a U-modifier convention across state lines.

Payers split on whether provider-level modifiers are even wanted. Some infer the credential from the code and reject the modifier as redundant. Others deny the claim without it. Both behaviors are common, which is why the aba modifiers question can't be answered generically.

Unbundling modifiers follow a separate set of rules that rarely apply to routine ABA claims. Our guide to modifier 59 rules covers when they legitimately do.

Telehealth Modifiers and Place of Service

Get these three definitions straight, because at least one widely shared ABA billing brief has them backwards.

GT indicates a service delivered via interactive audio and video. Synchronous. Medicare retired it for most professional claims, but several state Medicaid programs and TRICARE still require it.

95 indicates a synchronous telemedicine service delivered via real-time interactive audio and video. Same modality as GT, different vintage.

GQ indicates an asynchronous, store-and-forward service. Not live.

Place of service is a separate field with its own trap. POS 02 is telehealth provided somewhere other than the patient's home. POS 10 is telehealth provided in the patient's home, added in January 2022.

Most ABA telehealth reaches a child at home, so POS 10 is frequently the correct code. Defaulting to 02 is a preventable denial that also pays less, since Medicare pays POS 10 at the non-facility rate and POS 02 at the facility rate. Our place of service codes reference covers the full set.

Payer requirements layer on top. Some want the modifier, some want the POS code, some want both. TRICARE's ACD permits virtual health only for 97156, and only after the first six-month treatment period has been completed in person, with GT or 95 on the claim.

State the 2026 telehealth position precisely, because most sources state it loosely. Effective January 1, 2026, all ten adaptive behavior codes sit on the permanent CMS telehealth list, after CMS eliminated the provisional designation in the 2026 final rule.

That's a Medicare designation. Commercial payers and state Medicaid programs write their own telehealth rules and aren't bound by it.

Indiana proves the point. It removed telehealth from 97151, 97152, 97153, 97154, and 0373T in April 2026, three months after the aba cpt codes 2026 permanent designation took effect. Our telehealth CPT codes for 2026 guide tracks the broader list, and the Coalition's CMS final 2026 fee schedule summary documents the change.

Payer-Specific ABA Unit Caps and Billing Limits

The AMA descriptor tells you what a code means. It doesn't tell you how many units your payer will pay on a single date. Those limits live in provider manuals, they vary enormously, and the examples below are published numbers rather than estimates.

TRICARE Autism Care Demonstration

TRICARE publishes the most operationally specific ABA rules of any payer, which makes the TRICARE Autism Care Demonstration manual a useful documentation model even for practices that never bill TRICARE.

Published limits include a daily and weekly ceiling on 97153, commonly 32 units per day and 160 units per week before a clinical necessity review triggers. Per-provider daily caps apply across the code set.

Two more restrictions catch people out. Virtual health is limited to 97156 after the initial in-person period, and concurrent billing is excluded across the Category I codes except in that narrow family-and-beneficiary scenario.

The rule that costs practices the most is easy to miss. At least one 97155 service per month has to be rendered by the authorized ABA supervisor.

Miss it and the penalty isn't limited to that month. Regional contractors run a post-payment review and recoup 10% of all ABA claims for that beneficiary across the entire six-month authorization period. Our TRICARE credentialing requirements guide covers the certification steps that come first.

State Medicaid Programs

Every state sets its own caps, and state policy is now changing in response to federal enforcement rather than budget cycles alone.

Nevada limits all ABA services under 97153, 97155, and 0373T to 15 to 25 hours per week under a focused delivery model, and 25 to 40 hours per week under a comprehensive model, exceedable with prior authorization and documented medical necessity. The Nevada Medicaid ABA billing guide also caps assessments at one every 180 days without authorization.

Indiana rewrote its entire ABA benefit after its federal audit. Bulletin BT202627, issued February 26, 2026 and effective April 1, carries six changes at once:

• A 6% rate reduction on individual ABA services, with another 4% scheduled for April 2027
• A 4,000-hour lifetime cap on comprehensive ABA
• Weekly caps of 30, 32, and 38 hours by ASD level
• A supervision floor of one BCBA hour per eight RBT hours
• Caregiver coaching of up to 18 hours per six-month authorization under 97156
• Removal of telehealth from five codes

A separate bulletin requires accreditation. And in June 2026, CMS approved a six-month moratorium on new ABA provider enrollments in the state.

Rules that held last year may not hold this year. Our Medicaid provider enrollment guide covers the state-by-state variation in getting enrolled in the first place.

Commercial Payers

Commercial rules are less uniform and less published. Some payers waive precertification for assessment codes when an autism diagnosis is already on file. Others require separate authorization for assessment and treatment, with different renewal cycles for each.

Pull the actual provider manual for every payer in your mix and build a caps reference your billing team works from. Most practices don't have this document. It's the difference between catching a cap breach before submission and finding it on a remittance advice.

Tracking unit caps across 10 payers in three states is a full-time job most practices don't staff. MedSole RCM manages ABA billing services at 2.99% of collections, caps tracking included.

ICD-10 Codes for ABA Therapy and Medical Necessity

CPT tells the payer what you did. ICD-10 tells them why it was necessary. ABA claims fail on the second half more often than the first, because a valid code paired with an unsupported diagnosis is still a denial. Pairing the right aba cpt codes with the wrong diagnosis wastes the coding work entirely.

The Diagnosis Codes That Support ABA

F84.0, autism spectrum disorder, is the primary diagnosis supporting ABA coverage and the one most payers require. Related developmental diagnoses appear on some claims, and a few states cover ABA for conditions beyond autism. Nevada, for instance, covers ABA for ASD, FASD, or other conditions where it's recognized as medically necessary. Most payers restrict coverage to autism.

Documentation has to include a formal diagnostic evaluation by a qualified professional, updated on the payer's schedule. Several payers require periodic re-evaluation and will deny against a diagnosis that has aged past their window. TRICARE requires a new referral every two years.

One statistic worth getting right, because it's widely misquoted. CDC's ADDM Network estimates that about 1 in 31 children aged eight has been identified with autism spectrum disorder, or 32.2 per 1,000.

That figure comes from 2022 surveillance across 16 sites, published in April 2025. The 1 in 36 number still circulating is the earlier 2020 estimate. See CDC autism data and research for the current data.

When Multiple Behavioral Services Collide on One Date

Nobody in the competitive set cites this rule, and payers lean on it constantly.

When a patient requires psychiatric services, adaptive behavior services, and health behavior assessment or intervention services, CPT guidance instructs providers to report the predominant service performed. Medicare contractors apply it directly: the health behavior codes 96156 through 96171 aren't reported on the same day as psychiatric services 90785 through 90899 or adaptive behavior services 97151 through 97158.

That resolves a confusion that costs practices real money, since the 9715x adaptive behavior family and the 96156 to 96171 health behavior family get conflated constantly. They're separate families with separate rules, and our CPT and HCPCS code differences guide covers where HCPCS codes fill the gaps some payers leave.

When two behavioral services overlap on one date, decide which was predominant, document the decision and the reasoning, and expect to defend it. Correct-coding policy is published through the CMS Medicaid NCCI program and updated quarterly.

Why ABA Claims Get Denied, by Denial Code

A denial code tells you what the payer objected to. It rarely tells you why the claim got built that way, and it never tells you which of the ABA CPT codes triggered it. In ABA the same five or six codes recur, and each traces back to a specific upstream decision.

Table caption: Common ABA denial codes and what actually caused them

Two of these deserve a closer look.

CO-197 is the highest-volume ABA denial because ABA runs the most authorization-dense workflow in behavioral health. Assessment and treatment authorize separately, and treatment authorizations typically run three to six months.

Do the arithmetic. A practice with 30 active clients has roughly five authorizations expiring every month, and every date of service after a lapse is a retroactive denial. Our CO-16 denial code guide covers the documentation gaps behind the second-largest category.

CO-97 in ABA usually means concurrent billing got rejected. Before appealing, check which of the three layers from the 97153-versus-97155 section applies.

If your contract permits concurrent billing and two different individuals met the descriptor requirements, the appeal has a basis. If the payer prohibits it by policy, it doesn't. Our CO-97 bundling denials guide covers what to do instead.

Reworking a denial fixes one claim. Finding the pattern behind it prevents the next 10. Categorize by reason code, trace back to the workflow step that created it, and fix it there.

Denials that keep coming back aren't a billing problem, they're a workflow problem. MedSole RCM's root-cause denial review is free, and standalone denial management runs 4.49% of recovered revenue.

The 2027 ABA CPT Code Overhaul: Every New, Revised, and Deleted Code

At its September 2025 meeting, the AMA CPT Editorial Panel approved the largest revision to the adaptive behavior code set since 2019. Six new codes, revised descriptors for all eight Category I codes, revised guidelines, and deletion of both Category III codes, all effective January 1, 2027.

CMS published the proposed descriptors on July 14, 2026, inside the 2027 Medicare Physician Fee Schedule proposed rule. That publication is the only reason anyone can read them yet.

What Is and Is Not Final

The descriptor language is public through the CMS proposed rule. The code numbers are not. They appear as placeholders, 97X1X through 97X6X, and final numbers arrive with the 2027 CPT Professional Edition later this year.

The proposed rule carries a 60-day public comment period and isn't final policy until the 2027 MPFS final rule publishes in November 2026. Both documents can change.

The Coalition has asked providers and payers not to reconfigure EMR systems until the AMA publishes. That's the right call. Read the descriptors, plan around them, and hold off on the build. You can track it through the ABA Coding Coalition 2027 summary and the AMA CPT Editorial Panel actions record.

The Six New Codes

Table caption: Six new ABA CPT codes effective January 1, 2027

Four structural shifts, stated plainly.

Terminology moves from "destructive behavior" to "harmful behavior" across the multi-technician codes.

The on-site QHP requirement disappears from the descriptor text. Current 0362T and 0373T both require the QHP to be on site, immediately available and interruptible.

The proposed 97X1X and 97X4X descriptors specify two technicians, a patient who exhibits harmful behavior, and a customized environment. No on-site element. Watch that one through the final rule, since supervision expectations may move into the section guidelines rather than vanish.

Multi-technician services move from single T-codes to a base-plus-add-on structure. Technician counts have to be documented per session rather than inferred, and the two add-on codes aren't symmetrical: 97X2X covers additional technicians as a group, while 97X5X reports each additional technician.

97X3X is the one that changes practice economics. It recognizes QHP work performed away from the patient, which the current code set doesn't capture at all outside 97151. For practices where BCBAs spend hours weekly on data review, protocol modification, and transition planning, that's new billable time.

What Changes in the Existing Codes

The revisions aren't cosmetic.

97155 changes the most. The current descriptor reads "adaptive behavior treatment with protocol modification." The proposed descriptor reads "adaptive behavior direction of technician and analysis by physician or other qualified health care professional, face-to-face with a patient, each 15 minutes."

Protocol modification leaves the code entirely. 97155 becomes the direction and analysis code, and 97X6X takes over QHP direct treatment.

97156 adds "with analysis" plus the explicit caregiver-training language quoted earlier, which addresses the parent-update-versus-training ambiguity driving current denials.

97157 adds "with analysis" and shifts from "guardian(s)/caregiver(s)" to "multiple sets of caregivers for multiple patients." 97158 adds "with analysis" and drops "with protocol modification."

97152, 97153, and 97154 have the phrase "under the direction of a physician or other qualified health care professional" removed from the descriptor text. Supervision requirements move into the section guidelines rather than disappearing.

97151 sees minor wording changes only: "caregiver(s)" replaces "guardian(s)/caregiver(s)," and the and/or constructions get tightened.

2026 to 2027 Crosswalk

Table caption: ABA CPT codes crosswalk, 2026 to 2027

That aba cpt codes crosswalk answers a question the search results currently can't. The only crosswalk ranking today is an eight-year-old association PDF mapping the 2014 to 2019 transition.

Two more provisions worth knowing. CMS extended carrier pricing through 2027 for the existing codes and the six new ones, so there's still no national fee schedule and every rate stays negotiated.

On telehealth, CMS proposes keeping 97151 through 97158 on the permanent list for 2027 and said nothing about the six new codes. The Coalition plans to request their addition during the comment period. You can read the proposal in the CMS proposed 2027 fee schedule, pages 146 to 149.

What to do between now and January. Don't rebuild EMR code tables yet.

Do audit whether your session notes already capture technician counts, because the base-plus-add-on structure depends on it. Do check whether your BCBAs log non-face-to-face time separately, since 97X3X only pays if that time is captured. And call payers about authorizations spanning January 1, 2027, because those may need a mid-stream code change.

What Federal Audits Found in Medicaid ABA Claims

The HHS Office of Inspector General has audited Medicaid ABA payments in four states so far, with more announced. None of the findings turn on misreading the ABA CPT codes. The findings repeat closely enough to function as a compliance checklist.

Table caption: HHS OIG audits of state Medicaid ABA payments

Colorado's total, counting payments the OIG flagged as potentially improper, reached $285.2 million.

One finding matters more than the dollar figures. In every one of the four audits, all 100 sampled enrollee-months contained at least one improper or potentially improper claim line. Not most of them. All of them, in all four states.

The named deficiencies, which double as your fix list:

• Session notes lacking a full description of services, goals addressed, or data collected
• Unsupported CPT code billing, including excessive units
• Overlapping service times across providers
• Missing signatures and provider credentials
• Services rendered by staff without required credentials or supervision
• Billing of non-therapeutic or unallowable activities

Findings don't stop at recoupment. Indiana rewrote its ABA benefit after its audit, introducing the rate reductions, lifetime cap, and supervision ratio described earlier, and it's re-auditing the same dates of service the OIG examined. Federal audit findings become state policy, and state policy becomes your fee schedule. You can read the HHS OIG audit findings for each state directly.

Every deficiency on that list is a documentation and workflow problem. Practices don't fail these audits because nobody knew what 97153 means. They fail because the note didn't prove what the claim asserted. Our guide to audit-ready documentation covers the review process that catches this before a request letter arrives.

Audit-ready documentation isn't something you build after the letter shows up. MedSole RCM reviews every claim against payer rules and provider documentation before submission, at 2.99% of collections.

What ABA Billing Services Cost, and What to Ask Before You Hire

What ABA Billing Services Actually Cost

Full-service medical billing typically runs 4% to 7% of collections. Many companies add setup fees, per-claim charges, software fees, or monthly minimums on top of the percentage, so the headline rate and the effective rate often differ.

Credentialing gets priced separately. Market rates for ABA credentialing run roughly $200 to $500 per payer for a group plus one provider, with additional per-provider fees and separate charges for state Medicaid enrollment and CAQH management. Credentialing five payers for two BCBAs and three RBTs commonly lands between $5,000 and $12,000 before maintenance fees.

MedSole RCM charges 2.99% of collections for full-service medical billing, with no setup fees, no software fees, and no long-term contract. Credentialing is $99 per payer, with enrollment typically completed in 30 to 45 days. That's roughly half the industry billing rate and roughly a quarter to a fifth of typical per-payer credentialing pricing.

Denial management is included at no separate charge inside full-service ABA billing support, or available standalone at 4.49% of recovered revenue. Practices pricing ABA credentialing services should evaluate both pieces together, since credentialing delays cost more than credentialing fees.

What to Ask Before You Hire

Finding the best medical billing company for an ABA practice comes down to six questions. Ask them of every vendor you evaluate, including us.

Have you billed ABA specifically, or behavioral health generally? The codes behave differently. Concurrent billing, unit caps, and the credential-to-code mapping have no equivalent in outpatient psychotherapy.

Which unit rule do you apply per payer, and can you name it for my top three payers? If they can't, they're guessing, and guessing wrong for six months creates a repayment liability.

How do you track authorizations? With three to six month cycles and separate assessment and treatment authorizations, a 30-client practice has roughly five expiring every month.

Is credentialing included or billed separately, and what's the per-payer price? These bcba billing codes only pay when the rendering provider is enrolled, so credentialing isn't a side service.

What happens when a denial repeats? Resubmission isn't denial management. Root-cause correction is.

What's your clean claim rate and average days in AR for ABA specifically? Blended numbers across all specialties hide ABA performance.

If you want to see those numbers for your own practice before committing to anything, MedSole RCM runs a free billing analysis. Medical billing at 2.99% of collections, credentialing at $99 per payer.

ABA CPT Codes: Frequently Asked Questions

What are the ABA billing codes?

ABA billing codes are the 10 Adaptive Behavior Services codes the AMA maintains for applied behavior analysis. Eight are Category I permanent codes: 97151 and 97152 for assessment, and 97153 through 97158 for treatment and caregiver guidance. Two are Category III temporary codes, 0362T and 0373T, both covering multi-technician services for destructive behavior. All 10 bill in 15-minute units. Three of them, 97152, 97153, and 97154, are rendered by a behavior technician under QHP direction. The remaining Category I codes are rendered by the physician or other qualified healthcare professional, usually a BCBA. Both T-codes are deleted effective January 1, 2027.

What are the new ABA CPT codes?

Six new codes take effect January 1, 2027. They currently appear as placeholders because the AMA hasn't published final numbers. 97X1X covers behavior identification supporting assessment of harmful behavior with two technicians in a customized environment, and 97X2X is its add-on for additional technicians. 97X4X covers treatment of harmful behavior under the same conditions, with 97X5X as its per-technician add-on. 97X3X is entirely new: QHP non-face-to-face services including data review, protocol modification decisions, and discharge planning. 97X6X covers QHP direct treatment with analysis for one patient. Final numbers publish with the 2027 CPT Professional Edition in late 2026.

What are the new ABA billing codes in 2027?

Beyond the six additions, 2027 revises all eight Category I descriptors and deletes both Category III codes. 0362T and 0373T disappear, with their work moving to the new base-plus-add-on structure. The biggest revision hits 97155, which drops "protocol modification" and becomes "adaptive behavior direction of technician and analysis." QHP direct treatment moves to 97X6X. Codes 97156, 97157, and 97158 all add "with analysis." Codes 97152, 97153, and 97154 lose the "under the direction of" phrase from the descriptor, with supervision requirements moving into the section guidelines. Everything is proposed until the November 2026 MPFS final rule.

What is the difference between CPT 97153 and 97155?

97153 is protocol delivery by a behavior technician, face-to-face with one patient. 97155 is treatment with protocol modification by the physician or QHP, which may include directing a technician at the same time. The technician follows the plan; the QHP changes it. Documentation for 97155 has to show what changed, why, and how the patient responded, or the claim gets downcoded. On January 1, 2027 this distinction changes: 97155 becomes direction of technician and analysis, and QHP direct treatment moves to a new code currently placeholdered as 97X6X.

How many units of 97153 can be billed per day?

There's no universal number. The Medicare and Medicaid MUE for 97153 both sit at 32 units, or eight hours, per date of service. Your payer's own cap may be lower and often is. TRICARE's Autism Care Demonstration commonly caps 97153 at 32 units per day and 160 per week before triggering a clinical necessity review. Nevada Medicaid limits all ABA services to 15 to 25 hours weekly under a focused model and 25 to 40 under a comprehensive model. Indiana caps weekly hours at 30, 32, or 38 by ASD level. Check the provider manual, not a coding guide.

Can 97153 and 97155 be billed on the same day?

CPT permits it, with two conditions. The descriptor requirements for both codes have to be met, and a single QHP can't report both concurrently, so two different individuals must render the two services. Payer policy is a separate question and many payers restrict or deny concurrent billing regardless of CPT intent, with some paying the higher-rate code and denying the other. TRICARE's Autism Care Demonstration prohibits concurrent billing across the Category I codes, with a narrow exception where the family and beneficiary receive separate services and the beneficiary isn't present.

Is 23 minutes one unit or two?

Two units, under both rules that normally apply. CPT reports a unit once the midpoint of the time increment passes, which for a 15-minute code means work of 8 to 22 minutes is one unit and 23 minutes crosses into the second. The Medicare 8-minute rule produces the same answer: 23 to 37 minutes is two units. The rules agree. What changes the answer is a payer contract requiring full 15-minute increments with no rounding, in which case 23 minutes is one unit and the extra eight minutes aren't billable. That's a contract question rather than a coding question.

What ICD-10 code is used for ABA therapy?

F84.0, autism spectrum disorder, is the primary diagnosis supporting ABA coverage and the one most payers require. A few state Medicaid programs cover ABA for other conditions where it's recognized as medically necessary, but coverage restricted to autism is the norm. Claims need a formal diagnostic evaluation by a qualified professional on file, updated on the payer's schedule. Several payers require periodic re-evaluation and will deny against a diagnosis that has aged past their window, and TRICARE requires a new referral every two years.

Which ABA CPT codes can be billed via telehealth?

Effective January 1, 2026, all 10 adaptive behavior codes sit on the permanent CMS telehealth list, after CMS removed the provisional designation in the 2026 final rule. CMS proposes keeping 97151 through 97158 on that list for 2027. A Medicare designation isn't payer policy. Commercial payers and state Medicaid programs set their own rules and frequently diverge. Indiana removed telehealth from 97151, 97152, 97153, 97154, and 0373T in April 2026. TRICARE's Autism Care Demonstration permits virtual health only for 97156, and only after the first six-month treatment period is completed in person.

What modifiers are used with ABA CPT codes?

Provider-level modifiers carry the credential: HO for master's level, typically a BCBA; HP for doctoral level; HN for bachelor's level, typically a BCaBA; and HM for less than bachelor's level, typically an RBT. U1 through U9 are state-defined and have no national meaning, so never carry a convention across state lines. For telehealth, 95 and GT both indicate synchronous audio and video, while GQ indicates asynchronous store-and-forward. Some payers require the modifier, some require only the place of service code, and some require both.

Are 0362T and 0373T being deleted?

Yes, effective January 1, 2027. Both Category III codes disappear when the 2027 CPT code set takes effect, and the work moves into a new base-plus-add-on structure. 0362T's assessment work moves to 97X1X with 97X2X as the add-on for additional technicians. 0373T's treatment work moves to 97X4X with 97X5X as the per-technician add-on. Terminology shifts from "destructive behavior" to "harmful behavior." Some payers dropped the T-codes years ago, so check your contracts before assuming they're still active in your mix.

How much do ABA billing and credentialing services cost?

Full-service medical billing typically runs 4% to 7% of collections, often with setup fees, per-claim charges, or software fees added on top. ABA credentialing runs roughly $200 to $500 per payer for a group plus one provider, with separate charges for state Medicaid enrollment and CAQH maintenance. MedSole RCM charges 2.99% of collections for full-service billing with no setup fees, no software fees, and no long-term contract, and $99 per payer for credentialing with enrollment typically completed in 30 to 45 days. Standalone denial management runs 4.49% of recovered revenue.