ABA Denial Management: How to Prevent and Resolve Claim Denials

After helping hundreds of ABA practices resolve billing issues, we've identified the 5 denial patterns that cost practices the most. Here's how to prevent them before they reach your revenue cycle.

Top 5 reasons ABA claims are denied and how to prevent them

1. Missing or incomplete documentation

Documentation errors are the #1 reason ABA claims get denied. When therapists are rushed or stretched thin, they’re more likely to write vague clinical notes and treatment plans that don't match billing codes. Insurance companies need the proof in your notes that ABA therapy was medically necessary.

What insurers are looking for:

• Complete intake assessments (VB-MAPP, ABLLS-R, or equivalent)
• Detailed treatment plans with specific, measurable goals
• Progress notes that link directly to those goals
• Data showing progress toward objectives
• Clear documentation of who provided the service and when

How to prevent incomplete documentation: 

1. Start with a documentation checklist. Before submitting any session note, check that it includes: the learner's name, date, time, provider credentials, specific behaviors targeted, data collected, and progress toward goals. 
2. Better yet, integrate a practice management platform that requires clinicians to complete all fields before they can close a session. This removes the guesswork and catches gaps instantly. Plus, it helps your clinical and billing teams work better together.

2. CPT coding errors and ICD-10 mismatches

ABA uses 10 main CPT codes, and each one has strict rules about when to use it. Many practices mix them up. Insurance companies have automated systems that check if your CPT code matches your ICD-10 diagnosis code. If they don't align, the claim is rejected.

Common CPT code mistakes that cause denials:

1. Billing 97151 when only a technician collected data. (97151 requires the BCBA's direct involvement in assessment, not just observation.)
2. Billing 97153 when a BCBA actively modifies the plan. (That's 97155, which reflects the higher-level analysis.)
3. Mismatching ICD-10 codes. (Using F84.1 for autism when the plan requires F84.0. Payers flag mismatches instantly.)

How to prevent it 

Train your entire billing team on ABA-specific coding. Then, create a reference guide that sits next to every billing workstation. ABA codes change, and you need to stay ahead, so check for updates regularly. 

A billing software will help you prevent errors. It flags mismatches, suggests correct codes, and tracks payer requirements. Your team brings judgment and training, while the system brings the speed and consistency. It catches problems in seconds instead of after a denial.

3. Missing proof that therapy was needed

Insurance companies need to be convinced that ABA therapy is medically necessary. Vague notes like "Client had a good session" don't cut it. 

Payers want to see that the learner's diagnosis aligns with their criteria, that ABA is the right treatment, and that progress is being made. Without this, they deny claims or may demand endless appeals.

Medical necessity in ABA means that:

• The learner has a documented autism spectrum disorder diagnosis
• ABA services directly address the behavioral or developmental challenges noted in that diagnosis
• There's measurable progress toward specific, functional goals
• The treatment plan is individualized, not generic
• Progress notes connect each session to the treatment plan

How to prevent missing proof that therapy was needed 

Train your clinicians to write notes that tell a story backed with data, one that tells insurers exactly why this learner needs ABA. When clinical documentation is specific from the start, your billing team doesn't have to guess what's medically necessary. And if a denial occurs, your appeal team uses your clinical notes as evidence to defend your case. 

4. Missing pre-authorization

You can deliver weeks of therapy before discovering that your claim isn't covered because you never got pre-authorization from the client’s insurance company. Or when authorization exists, it's expired or doesn't cover the hours you billed. By the time you realize it, the claim is already denied.

What pre-authorization covers: 

• Number of weekly therapy hours permitted
• Approved duration of treatment 
• Specific provider credentials allowed
• Service location (in-home, clinic, telehealth)

How to prevent pre-authorization denials 

Before the first session, verify eligibility and authorization. Call the insurer, get a letter, and file it. Check the authorization start and end dates, as many insurance plans require reauthorization every 90 days. Build this into your ABA intake workflow as a non-negotiable step one. 

If authorization isn't approved before you start therapy, you're taking a financial risk. Thankfully, an integrated ABA software helps your intake and billing staff get authorizations right. It ensures your intake team asks the right questions, and it tracks approvals automatically.

5. Late claim submission and timely filing

Payers have strict deadlines for claim submission, often 90 to 120 days from service delivery. A couple of missed deadlines, a few delayed authorizations, and you're outside the filing window. 

The claim is denied automatically, and resubmission is nearly impossible. There's usually no exception process. Once the deadline passes, the claim is gone.

How to prevent late claims submission

Create a claims submission schedule tied to your payer contracts. Know every deadline. Use your practice management software to flag claims before they get to the cutoff. 

Try not to batch claims; submit them in real-time as sessions are completed and documented. The sooner you bill, the sooner you get paid. 

How to resolve claim denials: A step-by-step process

Nobody likes to get a denied claim. But denials are fixable if you have a clear process. Here's how to resolve them systematically and get paid.

Step 1: Read the provided denial reason carefully 

Before anything else, read the provided denial reasoning word-for-word. Identify the exact reason for the denial. Is it a coding error? Missing documentation? Coverage issue? Authorization problem? Write it down. This specific reason determines everything that follows.

Call the payer if the letter is vague. Get clarity. Document who you spoke with, the date, and what they said. This creates a paper trail if you need to escalate later.

Step 2: Determine if it's a quick fix or an appeal 

Technical errors (wrong CPT code, typo in learner ID, missing authorization) can be resubmitted quickly, usually within days. However, medical necessity denials require building a case with clinical evidence and take weeks or months to resolve.

Ask yourself: Is this something we can correct and resubmit? Or do we need to appeal with supporting documentation? That answer determines your next steps.

Step 3: Gather all your documentation 

Collect the original claim submission, the denial letter, treatment plans, progress notes, diagnostic assessments, prior authorization letters, and any previous payer correspondence. Organize it chronologically so you can tell a clear story about why this learner needed ABA.

Create a denial file (folder or spreadsheet) that includes the date denied, reason, action taken, and outcome. This becomes your knowledge base and protects you if things escalate.

Step 4: Resubmit technical errors or build an appeal

For technical errors (coding, missing info): Correct the error immediately. Create a cover letter that says: "This claim was previously denied due to [specific error]. We have corrected [the error] and are resubmitting for processing." Attach the corrected claim and submit within 5 business days.

For medical necessity denials: Prepare a formal appeal package that includes:

• A cover letter explaining why the denial was wrong and referencing the specific policy that should have approved the claim
• The learner's diagnostic assessment, showing autism spectrum disorder
• The treatment plan with specific, measurable goals
• Progress notes from the past 30-60 days showing measurable improvement
• A letter from the BCBA explaining why ABA is medically necessary for this specific learner
• Any prior approvals or medical necessity letters from other payers

Your appeal tells a story: This learner has autism. ABA directly addresses their needs. They're making progress. And here's why ABA is medically necessary.

Step 5: Submit and track everything 

Submit your resubmission or appeal within the payer's timeline (usually 30-60 days from the denial date). Get written confirmation of receipt. Log the submission date, time, and who received it. Then follow up every 2-3 weeks. 

Step 6: Document the outcome and improve your process 

When the outcome comes through (approved or denied again), document it. Track the denial reason, action taken, timeline, and result.

If you see the same denial reason repeatedly, it's a system problem. Ten coding denials mean your billing team needs more training on ABA-specific codes. Repeated "missing medical necessity" denials mean your clinical staff needs guidance on what payers are looking for.

Use denials as teaching moments. Bring your top three from the month to a team meeting. Break down what went wrong. Then, discuss how to prevent it. 

When to request an external review 

If the payer denies your internal appeal and the reason was medical necessity, you have the right to request an external review. 

This means that an independent reviewer (not employed by the insurance company) will evaluate your case. External reviews often take 30-60 days but have a much higher approval rate for medical necessity denials, especially with strong clinical documentation.

If a denial seems unjust and internal appeals have failed, external review is often worth pursuing.

How Passage Health prevents denials before they happen

ABA practices with the lowest denial rates use software that flags errors before claims go out.

Passage Health links your intake process, billing system, and clinical notes into one platform, eliminating data gaps that cause claim rejections.

Here's how it prevents the five denial types covered in this guide:

• Real-time error detection: Built-in detections catch claim errors before submission, flagging missing diagnosis codes or provider NPIs, unconverted session notes, and mismatches between session duration or location and the scheduled appointment. Incomplete notes are instantly sent back to clinicians for correction.
• Integrated authorization tracking: Every session gets checked against active authorizations automatically. Your system alerts you if a learner's authorization has expired, their hours are maxed out, or new approval is needed.
• Automated compliance checks: Verify that claims include medical necessity language, correct modifiers, and ABA-specific codes before submission.
• Denial tracking and insights: When denials do happen, built-in analytics show you exactly where they occur most often, whether it's coding, documentation, or payer-specific rules. Use these insights to train your team and refine workflows.
• Unified team visibility: Every team member can access the session information and see real-time claim data relevant to their role, so everyone works together to prevent issues, allowing faster claim processing and better performance across your practice. 

From verifying insurance coverage during intake to submitting accurate claims to tracking corrections in real time, Passage Health helps you fix issues before they cost you money.

Ready to reduce denials and get paid faster? Schedule a demo to see how Passage Health works for your practice.

Frequently asked questions

How can ABA practices prevent insurance denials? 

ABA practices can prevent insurance denials by starting with eligibility verification before the first session. Practices should also:

• Ensure every treatment plan is detailed and measurable. 
• Document every session with clear links to goals. 
• Use the correct CPT code for every service. 
• Submit claims before filing deadlines. 
• Use a practice management system that flags errors and tracks authorizations.

Do coding errors affect ABA billing denials? 

Yes, coding errors trigger immediate billing denials. You can prevent most coding denials by training your billing team and using automated code verification.

What are best practices for managing ABA claim denials? 

The best practices for managing ABA claim denials include: 

• When a denial arrives, read it carefully to understand the specific reason. 
• Gather supporting documentation (treatment plans, progress notes, assessments). 
• If the reason is an error, resubmit with corrected information. If it's a coverage issue, check the learner's policy directly. 
• Consider an appeal if the denial seems incorrect. 
• Track denial patterns. If you see the same issue repeatedly, it's a systemic problem worth fixing.

How can software improve the denial management process? 

Practice management software improves denial management by catching errors in real-time, tracking authorizations and expiration dates, and auditing claims for compliance. 

A unified practice management software integrates with eligibility verification and offers a central dashboard that your entire team can access. 

How can training improve ABA denial management efficiency? 

ABA billing training improves denial management efficiency by helping clinical and billing staff understand the specific coding and documentation requirements.

When your team understands what is important, they catch their own errors before billing and collaborate more effectively. 

References

American Medical Association. (n.d.). CPT code guidance for behavioral health services. Retrieved from https://www.ama-assn.org/

Behavior Analyst Certification Board. (2023). BACB professional and ethical compliance code for behavior analysts. https://www.bacb.com/wp-content/uploads/2023/08/2023-bacb-professional-ethical-compliance-code-for-behavior-analysts-pdf.pdf

Center for Medicare & Medicaid Services. (n.d.). ICD-10-CM diagnosis code lookup. Retrieved from https://www.cms.gov/medicare/coding-billing/icd-10-codes

Centers for Medicare & Medicaid Services. (n.d.). Medicaid program information. Retrieved from https://www.medicaid.gov/

Kruschwitz, R., & Falk, H. (2020). Addressing the growing demand for autism services. Harvard Health Policy Review, 18(2), 42---51.

National Institute of Mental Health. (2021). Autism spectrum disorder. U.S. Department of Health and Human Services. https://www.nimh.nih.gov/health/statistics/autism-spectrum-disorder-asd

U.S. Department of Health and Human Services. (2021). HIPAA Privacy Rule and Security Rule guidance documents. Retrieved from https://www.hhs.gov/hipaa/

Passage Health. (n.d.). ABA practice management and EMR/EHR software for autism therapy. Retrieved from https://www.passagehealth.com/