ABA therapy is one of the most effective treatments for autism. It is also one of the most expensive. With annual costs frequently exceeding $100,000 per child, even small billing errors add up fast. And some of those "errors" are not errors at all.
As the founder of ESBAP and someone who has spent 16 years in the ABA industry, I have seen billing practices range from impeccable to genuinely fraudulent. Most families never look closely at their ABA bills because the insurance company is paying. But your insurance company's willingness to pay does not mean the charges are accurate, and billing problems have a real cost to your child's care.
This guide will walk you through how ABA billing works, what the most common problems are, and exactly what you should demand from your provider.
How ABA Billing Works: A Quick Primer
ABA therapy is billed using CPT codes (Current Procedural Terminology), the same coding system used across all healthcare. Each code represents a specific type of service. Here are the codes you are most likely to see on your child's ABA bills:
| CPT Code | Service | Who Delivers It |
|---|---|---|
| 97151 | Behavior assessment (initial and ongoing) | BCBA |
| 97153 | Adaptive behavior treatment (direct therapy) | RBT or behavior technician |
| 97155 | Treatment with protocol modification | BCBA (higher reimbursement rate) |
| 97156 | Family/caregiver training | BCBA |
| 97158 | Group adaptive behavior treatment | RBT or BCBA |
Each code is billed in 15-minute units. So if your child has a two-hour therapy session delivered by an RBT, the provider bills 8 units of CPT code 97153. The reimbursement rate varies by state, insurance plan, and whether the payer is Medicaid or private insurance, but typically ranges from $50 to $125 per hour.
This system is straightforward when used honestly. The problems arise when it is not.
The Three Most Common ABA Billing Problems
1. Upcoding
Upcoding means billing a higher-rate code than the service actually delivered. In ABA, the most common form is billing under code 97155 (BCBA-delivered treatment, which reimburses at a higher rate) when the session was actually delivered by an RBT (which should be billed under 97153 at a lower rate). The difference can be $30 to $60 per hour, and across 30 hours per week over a year, that adds up to tens of thousands of dollars in inflated charges.
This is not a gray area. It is insurance fraud. If your child's daily sessions are delivered by an RBT but your Explanation of Benefits (EOB) shows 97155 charges for those same sessions, something is wrong.
2. Billing for Undelivered Services
Some providers bill insurance for sessions that did not happen. This includes billing for days your child was absent, billing for the full scheduled time when a session ended early, or billing for "indirect" services (like data review or team meetings) at direct-service rates. While providers do have legitimate billable activities that happen outside your child's sessions (such as treatment plan development under 97155), these must be documented and reflect actual work performed.
A 2024 OIG report found that billing for undelivered ABA services was among the most common Medicaid fraud allegations in behavioral health. Families are often the only ones who can catch this, because they know when their child was actually present.
3. Bundled or Unexplained Charges
Some providers send bills that show a single lump sum per month with no breakdown. Others include vague line items like "program materials" or "administrative fees" that are not tied to any CPT code. These charges may or may not be legitimate, but the lack of detail makes it impossible for families to verify. Ethical billing is specific: every charge tied to a date, a code, a provider, and a duration.
Billing Red Flags to Watch For
- Your EOB shows 97155 (BCBA) charges for days when only an RBT was present
- You are billed for a date your child was absent or a session that was canceled
- Monthly statements show lump sums with no line-item detail
- Your provider resists giving you an itemized statement when you ask
- You see charges for "materials" or "administrative fees" not explained in your service agreement
- The number of billed hours consistently exceeds the hours authorized in your child's treatment plan
- Your provider becomes defensive or evasive when you ask billing questions
Why This Problem Is Getting Worse
The ABA industry has grown rapidly. Autism diagnoses have risen to 1 in 36 children, all 50 states now mandate autism insurance coverage, and Medicaid has become a major payer for ABA services. This growth has attracted significant investment, particularly from private equity firms that now back the majority of ABA acquisitions.
When growth is driven by financial targets rather than clinical outcomes, billing practices tend to follow. Providers under pressure to increase revenue may authorize more hours than clinically necessary, upcode sessions, or resist reducing treatment as children progress.
State Crackdowns Are Already Happening
Nebraska reduced ABA Medicaid spending by approximately 80% after an audit found widespread overbilling and services that lacked clinical justification. Indiana implemented session caps for Medicaid-funded ABA services. These are not isolated events. They reflect growing awareness among state agencies that ABA billing practices require closer oversight. When states respond with broad cuts, families who depend on Medicaid funding are the ones who lose access, even when their provider was billing honestly.
This is the core problem: billing fraud by some providers results in tighter restrictions that affect all families. Every overbilled session makes it harder for the next child to get the care they need.
What Ethical ABA Billing Looks Like
Signs of Ethical Billing
- Itemized statements showing each date of service, CPT code, number of units, treating provider name, and session start/end time
- Plain-language explanations of what each code means, provided proactively (not only when you ask)
- Clear cancellation policy in your service agreement, with a distinction between cancellation fees and insurance billing
- Treatment hours that match the clinical plan, not a revenue target. Hours should decrease as your child progresses
- Willingness to answer questions about any charge without becoming defensive or evasive
- Authorization requests tied to clinical data, not the maximum your insurance will approve
Ethical providers view billing transparency as a sign of quality, not an inconvenience. If your provider treats your billing questions as a nuisance, that tells you something important about their priorities.
What to Ask Your Provider
10 Billing Questions Every Family Should Ask
- "Can I receive an itemized statement for every billing period showing dates, codes, units, and provider names?"
- "What CPT codes do you typically bill for my child's services, and what does each one mean?"
- "Will I ever be billed for a session my child did not attend?"
- "What is your cancellation policy, and is it in writing?"
- "Who determines how many hours of therapy my child receives, a clinician or an administrator?"
- "How do you decide when to request an increase or decrease in authorized hours?"
- "Are there any charges (materials, assessments, administrative fees) that are billed separately from therapy sessions?"
- "Can you explain the difference between 97153 and 97155 charges on my statement?"
- "What percentage of my child's sessions are delivered by an RBT versus a BCBA?"
- "If I disagree with a charge, what is the process for disputing it?"
A provider who answers these questions clearly, without hesitation, is one that values billing transparency. A provider who cannot answer them, or who discourages you from asking, is telling you something you need to hear.
Billing Transparency as an Ethics Indicator
At ESBAP, billing transparency is one of our 7 Key Ethics Indicators (KEI) that we use to evaluate ABA providers. It carries a 10% weight in a provider's overall ethics score, alongside indicators like supervision ratio, staff compensation, training quality, management ethics, work-life balance, and client outcomes.
We include billing as an ethics indicator because it is both a quality signal and a protection for families. Providers who bill transparently tend to operate transparently in other areas too. The reverse is also true. A provider that obscures its billing is more likely to have problems in supervision, staff retention, or clinical outcomes.
You can check any provider's billing transparency rating, along with their full ethics profile, on the ESBAP provider directory. We track over 8,500 ABA organizations and include data on accreditation, ownership, clinical leadership, and ethics ratings submitted by employees and families.
What to Do If You Find a Problem
If you spot a discrepancy between your records and your provider's billing, start by contacting the provider's billing department directly. Many billing errors are genuine mistakes, especially at smaller organizations where billing staff may be stretched thin. Give them a chance to explain and correct.
If the provider cannot explain the charges, or if you see a pattern of overbilling, escalate. File a complaint with your insurance company's fraud department. If your child's services are funded by Medicaid, contact your state's Medicaid Fraud Control Unit. You can also file an ethics complaint with the BACB Ethics Department, and submit a billing transparency rating on the provider's ESBAP profile.
You should not feel guilty about questioning your provider's billing. You are not being difficult. You are doing exactly what responsible oversight looks like.
Check Your Provider's Ethics Rating
ESBAP's free directory includes billing transparency ratings, accreditation status, ownership data, and clinical leadership information for over 8,500 ABA organizations.
Search the Directory Parent ResourcesFrequently Asked Questions
What CPT codes are used for ABA therapy billing?
The most common codes are 97151 (assessment), 97153 (direct treatment by an RBT), 97155 (treatment with protocol modification by a BCBA), 97156 (family/caregiver training), and 97158 (group treatment). Code 97153 is the most frequently billed because it covers one-on-one therapy sessions.
How can I tell if my ABA provider is billing correctly?
Request an itemized statement for every billing period. Each line should show a date, CPT code, units billed, provider name, and session times. Compare this against your own records of when your child attended sessions and who delivered them.
What is upcoding in ABA therapy?
Upcoding is billing a higher-rate code than the service that was delivered. The most common example is billing 97155 (BCBA rate) for a session that was actually delivered by an RBT (which should be billed under 97153). This is insurance fraud.
Can my provider bill me for missed sessions?
A provider may charge a cancellation fee per your service agreement, but cannot bill insurance for services that were not delivered. If your EOB shows a charge for a date your child did not receive therapy, that is a billing error or fraud.
Why is ABA therapy so expensive?
ABA therapy is intensive (often 20 to 40 hours per week of one-on-one treatment), which drives the high annual cost. Most families have coverage through insurance mandates or Medicaid, but the high dollar amounts also make ABA billing a target for fraud.
What should I do if I suspect billing fraud?
Start by requesting itemized records and asking your provider to explain. If the issue persists, file a complaint with your insurance company, your state's Medicaid Fraud Control Unit (for Medicaid-funded services), or the BACB Ethics Department. You can also report billing concerns through ESBAP's provider profiles.
How does ESBAP evaluate billing transparency?
Billing transparency is one of ESBAP's 7 Key Ethics Indicators, carrying 10% weight in a provider's ethics score. ESBAP evaluates whether providers offer itemized billing, explain CPT codes to families, maintain transparent cancellation policies, and avoid common billing problems.