2027 ABA CPT Codes: 6 New Codes, the 97155 Split and Deleted T-Codes

By DocMBS Billing Team · Last updated: October 2026

The 2027 ABA CPT codes take effect on January 1, 2027, and they change more than any ABA code update since 2019. Six new codes arrive, 97155 is split in two, and the Category III codes 0362T and 0373T are deleted. If your authorizations, fee schedules or practice software still use the 2026 codes in January, expect denials on day one.

This guide gives you the full 2027 ABA code list, a 2026-to-2027 crosswalk, a simple way to choose between 97155, 97173 and 97180, and a quarter-by-quarter plan for moving your authorizations over before December 31.

What Changed in the 2027 ABA CPT Codes

The AMA released the CPT 2027 code set on September 9, 2026. It includes 299 new codes, 74 revisions and 80 deletions, all effective January 1, 2027. Six of the new codes are for adaptive behavior services, the code family ABA providers use.

Here is the short version:

The ABA Coding Coalition, the group that worked with the AMA on these codes, published an official crosswalk on September 11, 2026. We use it throughout this guide.

Full List of 2027 ABA CPT Codes

All 14 codes below are reported in 15-minute units. The descriptions are short summaries in our own words. For the official descriptors, see the AMA CPT 2027 Professional Edition.

Source: ABA Coding Coalition, 2027 CPT Code Crosswalk (September 11, 2026). “+” marks an add-on code.

2026 to 2027 ABA Code Crosswalk

Use this table to update your authorizations, fee schedules and charge masters. It follows the ABA Coding Coalition crosswalk.

97155 vs 97173 vs 97180: Which Code Do You Use?

This is the change that will cause the most coding errors in 2027. In 2026, 97155 covered two different things: a BCBA directing a technician, and a BCBA treating the client directly. In 2027, those are separate codes, and a third code covers the BCBA’s work away from the client.

A simple test: ask “Who has hands-on contact with the client right now?” If it’s the technician and the BCBA is guiding them, use 97155. If it’s the BCBA, use 97173. If nobody is with the client, look at 97180.

How 97180 is reported

• It covers QHP work without the client: reviewing data and session notes, deciding on treatment changes, developing assessment protocols, discharge planning and technician training on protocols.
• You add up the non-face-to-face time over the preceding seven days (for example, Sunday to Saturday) and report it once per week.
• Keep a time log for each activity. A single weekly total without detail will not hold up in an audit.

Harmful Behavior Codes: 97148, 97149, 97159, 97160

These four codes replace 0362T and 0373T for clients with severe, destructive behavior who need a specially set-up environment and more than one technician.

• 97148 (assessment) and 97159 (treatment) are the base codes. Each requires two technicians working face-to-face with the client in a customized environment.
• 97149 and 97160 are add-on codes for each additional technician. The coalition crosswalk limits each code family to five technicians in total.
• The QHP must be on site. That means immediately available to help and direct throughout the session, but not necessarily in the room. The coalition notes that telehealth may meet this requirement where clinically appropriate, if the payer and state rules allow it.
• Add-on codes can never be billed alone. They must be on the same claim as their base code.

Worked Example: One Client, One Week in 2027

Example only. This is a fictional client, and unit rules vary by payer.

A BCBA and a technician serve one child in the week of January 10–16, 2027. Here is how the week is coded, using the CPT midpoint rule (a unit counts once you pass 7.5 minutes of a 15-minute unit). Check your payer’s own unit rule before billing.

How the 97180 units work: 70 minutes ÷ 15 = 4 full units with 10 minutes left over. Ten minutes is more than 7.5, so it counts as a fifth unit. Total: 5 units, reported once for the week.

What changes for this client:

• 4 units move from 97155 to 97173. If the authorization only lists 97155, those 4 units can deny as unauthorized.
• 5 units of 97180 are new. They are only payable if the payer covers the code and it is on the authorization.
• Over a 26-week authorization, that is about 104 units of 97173 and 130 units of 97180 you need to request.

Step-by-Step Authorization Transition Plan

Authorizations are where the 2027 ABA CPT codes will hurt most. Many current authorizations run past December 31, 2026 and list codes that stop existing or change meaning on January 1.

1. Pull every active authorization (October). List each client, payer, codes, units and end date. Flag any authorization that ends after December 31, 2026.
2. Flag the risky codes. Mark every authorization with 0362T, 0373T or 97155. These are the ones that need action.
3. Ask each payer how it will handle the switch (October–November). Get written answers to three questions: Will you convert existing authorizations automatically? Do we need a new request for 97173 and 97180? Will you cover 97180, and with what unit limit?
4. Estimate the 97155 split for each client. Review BCBA session notes from the last 1–2 months and estimate how much 97155 time was direct treatment. That share becomes your 97173 request.
5. Submit new or updated requests (November–December). For January start dates, request 97173, 97180 and the harmful behavior codes as needed. Keep 97155 for direction time only.
6. Split authorizations that cross December 31. Bill December dates of service with 2026 codes and January dates with 2027 codes, even if the authorization covers both. Never put 0362T or 0373T on a January 2027 date of service.
7. Update fee schedules and software (December). Add the six new codes, end-date 0362T and 0373T on December 31, 2026, and set rates for each payer.
8. Train BCBAs and technicians. Make sure session notes clearly show who delivered treatment and whether the client was present. That is what decides 97155 vs 97173 vs 97180.
9. Audit the first two weeks of January claims. Check the first remits for every payer before you bill the rest of the month.

Medicare, Medicaid and Commercial Payers

Commercial and Medicaid managed care

Under HIPAA, payers must accept valid CPT codes, but each one decides coverage, rates, unit caps and authorization rules. Expect some payers to be ready on January 1 and others to lag. Watch provider bulletins and fee schedule updates closely in November and December.

State Medicaid

Each state Medicaid program sets its own ABA fee schedule and code list. Some states did not cover 0362T or 0373T at all, and some may take months to add the new codes. Check your state’s provider manual and fee schedule before January.

Medicare

ABA codes are carrier priced under Medicare, so there is no national payment amount. In the CY 2027 Physician Fee Schedule proposed rule (July 2026), CMS kept carrier pricing for adaptive behavior codes through 2027 and proposed keeping 97151–97158 on the Medicare telehealth list. CMS did not address telehealth status for the six new codes in the proposed rule. The final rule is expected in November 2026.

Texas Medicaid ABA Note

Texas Medicaid has covered ABA since February 1, 2022 for members under 21 with an autism diagnosis, and every service needs prior authorization. Texas Medicaid managed care guidance lists these ABA codes: 97151, 97153, 97154, 97155, 97156 and 97158, plus 99366 for team conferences.

What this means for Texas ABA providers in 2027:

• 97155 time will need to be split. If Texas Medicaid adopts 97173, BCBA direct treatment currently billed as 97155 will likely move there. Until TMHP says so, don’t change your Texas Medicaid billing.
• Watch TMHP and your MCOs. At the time of writing, we had not seen a TMHP notice on adopting 97148, 97149, 97159, 97160, 97173 or 97180. Check TMHP banner messages and the Texas Medicaid Provider Procedures Manual (TMPPM) updates before January.
• Keep Texas limits in mind. MCO guidance lists a daily cap on direct treatment and requires re-evaluation every 180 days. New codes will likely come with their own limits.

Common Denials and How to Fix Them

ABA billing already runs on tight authorizations and unit caps, and January 2027 adds a new layer. If you want a team that tracks every payer’s code rollout for you, see our medical billing and RCM services.

FAQs

What are the new ABA CPT codes for 2027?

There are six new codes: 97148 and 97149 for harmful behavior assessment, 97159 and 97160 for harmful behavior treatment, 97173 for direct treatment by a BCBA or other qualified professional, and 97180 for the professional’s non-face-to-face work. All take effect January 1, 2027, and all are reported in 15-minute units.

Are 0362T and 0373T deleted in 2027?

Yes. Both Category III codes are deleted effective January 1, 2027. Harmful behavior assessment moves to 97148 plus add-on 97149, and harmful behavior treatment moves to 97159 plus add-on 97160. Using 0362T or 0373T for a 2027 date of service will usually deny as an invalid code.

What is the difference between 97155 and 97173?

In 2027, 97155 is for a BCBA directing a technician who is treating the client, with analysis. 97173 is for a BCBA treating the client directly, face-to-face, with analysis. In 2026, both activities were billed as 97155. Your session notes should clearly show which one happened.

How do you bill CPT 97180?

97180 covers a qualified professional’s work without the client present, such as data review, treatment decisions and protocol planning. You add up that time over the preceding seven days and report it once per week in 15-minute units. Keep a detailed time log, and confirm the payer covers the code first.

When do the 2027 ABA CPT codes take effect?

They take effect for dates of service on or after January 1, 2027. The AMA released the CPT 2027 code set on September 9, 2026. Services on or before December 31, 2026 must still be billed with the 2026 codes, including 0362T and 0373T where a payer covers them.

Do I need new authorizations for the 2027 ABA codes?

Often, yes. Many payers will require new or updated authorizations for 97173, 97180 and the harmful behavior codes. Some may convert existing authorizations automatically. Ask each payer in writing before January, and split authorizations that run past December 31, 2026 by date of service.

Does Medicare pay for the new ABA codes?

Medicare pays ABA codes through carrier pricing, so there is no national rate. The CY 2027 proposed fee schedule kept carrier pricing through 2027. It did not address telehealth status for the six new codes. The final rule, expected in November 2026, may add more detail.

Who can bill 97173?

97173 is billed for services delivered directly by a physician or other qualified healthcare professional, such as a BCBA or licensed behavior analyst, whose scope of practice includes ABA. Technicians cannot bill it. Payers may also require specific credentials or modifiers, so check each payer’s policy.

Get Ready for the 2027 ABA CPT Codes Now

The 2027 ABA CPT codes reward practices that prepare early. Map every authorization, split your 97155 time, ask payers about 97180 and remove 0362T and 0373T from January claims. Practices that wait until January will spend the first quarter fixing denials.

DocMBS handles ABA billing, authorizations and denial follow-up for behavioral health practices. Book a free ABA billing review and we’ll check your authorizations and fee schedules against the 2027 codes before January 1.

Sources

• American Medical Association: AMA releases CPT 2027 code set, September 9, 2026
• ABA Coding Coalition: 2027 CPT Code Crosswalk, September 11, 2026
• ABA Coding Coalition: CMS Releases Proposed 2027 Medicare Physician Fee Schedule, July 15, 2026
• Federal Register: CY 2027 Physician Fee Schedule Proposed Rule, July 16, 2026
• TMHP: Texas Medicaid Provider Procedures Manual

Last updated: October 2026. CPT® is a registered trademark of the American Medical Association. Code descriptions above are paraphrased summaries, not official CPT descriptors. This article is for education only; confirm coverage, units and authorization rules with each payer before billing.