CPT 97155 Audits: What Reviewers Pull and the 2027 Red Flags

A CPT code 97155 audit checks whether each billed unit is backed by a session note showing a BCBA or other QHP face to face with the client, directing a technician, and analyzing the client’s data. From January 1, 2027, expect them to also check that a technician code ran during the same time (ABA Coding Coalition supplemental guidance, p. 16).

This page is about preparing for a 97155 review. For what the code covers in 2026 and 2027, see the CPT 97155 guide; for a field-by-field note, see the 97155 note template; for audits across all ABA codes, see ABA insurance audit documentation.

What is the 97155 CPT code description an auditor checks against?

The auditor checks the note against the descriptor in force on the date of service. Through December 31, 2026 that is the 2019 wording: “Adaptive behavior treatment with protocol modification, administered by physician or other qualified healthcare professional, which may include simultaneous direction of technician, face-to-face with one patient, each 15 minutes” (Coalition crosswalk, p. 3).

From January 1, 2027, 97155 is no longer dual-use. It covers a BCBA or other QHP directing a technician, with analysis, while the technician works face to face with the patient, so it is normally billed alongside a technician code (97148, 97149, 97153, 97154, 97159 or 97160). The ABA Coding Coalition notes one uncommon exception: a QHP directing another QHP who leads a 97158 group. A BCBA treating the patient with no technician bills new code 97173, and 97155 and 97173 are not billed concurrently.

As of October 29, 2026. Sources: ABA Coding Coalition 2027 guidance and the CMS CY 2027 proposed rule. CPT is a registered trademark of the AMA.

An audit of 2027 claims will therefore test something a 2026 audit could not: whether there was a technician to direct. A 2026 note that shows a BCBA treating alone was valid 97155; the same note dated February 2027 describes 97173.

What do reviewers pull in a 97155 audit?

Requests differ by payer, so treat this as a typical list, not a rule. For a sample of 97155 claim lines, expect to be asked for:

• The session notes for every sampled date, for both the BCBA’s 97155 time and the technician’s session it overlapped.
• The treatment plan and assessment in force on those dates, so the reviewer can link the session to a goal.
• The authorization showing 97155 units, dates and rendering provider.
• Credentials of the BCBA and the technician on the date of service (certification, license where the state requires one, payer enrollment).
• Time records that match the units billed, such as EHR timestamps, schedules or electronic visit verification where the program uses it.
• Signatures on each note that meet the payer’s or state’s signature rules.
• Raw data: the data sheets or graphs the note cites.

Medicaid audits look at the same things. The HHS Office of Inspector General’s audit of Indiana’s ABA payments found that all 100 sampled enrollee-months included improper or potentially improper claim lines, and recommended guidance on “the detail in session notes needed to support ABA provided”, “State signature requirements” and “what the State agency considers billable ABA time”, including the services needed to support 97155 and 97156 (OIG report A-09-22-02002, December 2024).

How long to keep these records is set by your payer contracts and state law, not by HIPAA, which does not set a medical record retention period (HHS HIPAA FAQ).

Which 97155 documentation gaps get flagged?

Common gaps, drawn from the Coalition’s analysis rule and the OIG findings above (not a payer list):

Every 2027 code that includes analysis (97155, 97173, 97156, 97157, 97158 and 97180) has the same documentation rule: “Analysis activities by the QHP must be documented clearly in the corresponding session note(s)” (supplemental guidance, p. 2).

What are the new 97155 red flags in 2027?

From January 1, 2027, these pairings and patterns are errors under the Coalition’s reading of the new code set:

1. 97155 with no technician code for the same time. 97155 “will ALWAYS be reported with another technician-delivered CPT code” (p. 16); the only exception is a QHP directing another QHP’s 97158 group (p. 28). If the BCBA treated alone, the code is 97173.
2. 97155 and 97173 for the same time. “Reporting 97155 concurrently would be duplicative” (p. 31).
3. 97155 during a 97152 supporting assessment. Not reported together; a BCBA who attends 97152 cannot bill that time (p. 32).
4. One QHP billing 97153 and 97155 at once. “A single QHP may not report 97153 and 97155 concurrently” (p. 16).
5. 97155 for every child in a technician-led group. 97155 is reported only for the patients the BCBA directed (p. 17).
6. Protocol rewrites inside 97155 units. “The act of adjusting a written treatment protocol, goal, or target in the treatment plan is reported separately using 97180” (p. 22).
7. Unconverted 2026 authorizations. Billing 2027 dates against an authorization that still lists only 97155 units, when part of that time is now 97173 or 97180. Ask each payer whether authorizations convert automatically (Coalition provider guide, p. 2).

For the concurrency rules in full, see billing 97153 and 97155 together.

How do you run a 97155 self-audit before a payer does?

Pick ten recent 97155 notes across your BCBAs and score each one yes or no:

• Start and stop times present, and the units match the minutes (8-22 minutes is one unit; under 8 is not reportable, supplemental guidance p. 31)?
• BCBA name, credential and signature present?
• Technician named, with their code and times for the same period (2027)?
• Data reviewed during the session named, with numbers?
• A decision written for each target reviewed, including “no change”?
• Direction to the technician described in specific terms?
• Client response recorded?
• A treatment plan goal named?
• No overlap with the same BCBA’s 97173, 97153 or 97152 time?
• Units within the authorization for that date and code?

Any note under 8 of 10 (our suggested cutoff) is worth a correction plan: retrain on the missing fields, and check whether the claim needs to be corrected with the payer. For the 2027 changes across every code, see the 2027 crosswalk and ABA CPT codes.

What should you do when a 97155 audit request arrives?

1. Log the request. Note the deadline, the claim lines sampled and how records must be sent.
2. Pull the full record for each line, using the list above, before anyone edits anything.
3. Do not alter notes. If a note needs a late entry, add it as a dated, signed addendum that says when and why it was added; your payer’s rules decide whether it counts.
4. Check each line against the descriptor for its date of service, 2019 wording for 2026 dates and 2027 wording after.
5. Write a short cover letter that maps each claim line to its note, plan goal and authorization.
6. Track the outcome and fix the pattern behind any finding in your templates and training.

This page is billing information, not legal advice. For an active audit, talk to your compliance lead or a health care attorney. CPT is a registered trademark of the American Medical Association.

Reviewed by the Praxis Notes team on October 29, 2026.