Optum ABA Guidelines: Billing Policy, NPI Rules and 2027 Codes

Optum’s ABA billing rules for commercial plans are in its Applied Behavior Analysis (ABA) Reimbursement Policy - Commercial (policy 2022RP501A, last revised June 2026). It covers 97151-97158 with a credential modifier, plus 0362T and 0373T, and sets daily unit limits. As of October 29, 2026, Optum has published nothing about the 2027 ABA codes that we could find.

There is no separate Optum ABA provider manual for billing: the rules sit in this policy, listed on Provider Express under reimbursement policies, and in Optum’s Autism/ABA Using CPT Codes FAQ (January 2024), which says “All services require prior approval.” Plan-specific and state manuals can add to them, so check your contract.

This page walks through that policy, Optum’s rendering-provider NPI and taxonomy rule, and what the January 1, 2027 code changes mean for Optum claims. For every 2026 code mapped to its 2027 successor, see ABA CPT code changes for 2027; for all ABA codes and modifiers in one table, see ABA CPT codes.

What do Optum’s ABA guidelines say about billing?

The policy applies to “behavioral health benefits … administered by Optum, including but not limited to UnitedHealthcare members,” on Commercial and Individual Exchange plans. Its core rule: “Optum follows AMA and CMS industry standards and allows the following below reimbursable codes for the commercial ABA program,” and “The appropriate modifier must be billed to reflect the appropriate credentials of the provider delivering the services” (policy, p. 2). Units follow CMS’s counting for timed codes: 8 to 22 minutes is 1 unit, 23 to 37 minutes is 2 units, and so on (p. 2).

Which modifier goes with each credential?

Source: policy pp. 2 and 4. 0362T and 0373T “do not require modifiers” (p. 5) and are deleted from January 1, 2027. Bill one provider-level modifier per line: “Billing multiple provider-level modifiers (HN, HM, HO, HP) on the same service line … may result in claim denial” (Q&A 13).

What are Optum’s daily unit limits?

Source: policy p. 3. Optum adds that “MUE’s apply, per CMS guidelines,” and that 97153 claims over 32 units a day “may be subject to non-reimbursement or recovery” (Q&A 10).

What do the policy’s Q&As allow and deny?

• 97153 or 97154 with 97155: “Yes, as long as the criteria in the descriptors of both codes are met. A single QHP may not report 97153 or 97154 with 97155 concurrently” (Q&A 7).
• 97155 and 97156 on the same day: “Yes. However, the services must be separate, distinct, and clearly documented,” and “Services must occur at different times on the same day” (Q&A 11).
• Treatment planning while the RBT treats: not 97155. “Treatment planning is an indirect service and not eligible for reimbursement” (Q&A 9).
• Indirect time in general: “There is no CPT code for reporting indirect services separately. Indirect services must be bundled with direct services” (p. 2).
• Technician training: “CPT codes 97153 and 97155 may not be billed for technician training,” including training on treatment-plan updates (Q&A 12, added June 2026).
• Group sessions: “sessions that operate as group treatment should be billed as 97154,” not 97153 (Q&A 8).
• Assessment: “97151 and 97152 are the only codes eligible for reimbursement for assessment or reassessment activities,” and 97151 cannot be billed for indirect work alone, such as report writing (Q&A 5-6).

What has Optum said about the 2027 ABA codes?

Nothing yet. On October 29, 2026 we checked Optum’s ABA reimbursement policy (no 2027 text; it still lists 0362T and 0373T), its reimbursement-policy index on Provider Express and its quick reference guide on the 2025 CPT updates (posted February 2026). None mentions 97173, 97180 or the harmful-behavior codes. We found no UnitedHealthcare provider notice on them either.

That matters because the 2027 codes collide with several lines above (our reading of the policy against the Coalition’s 2027 guidance):

The Coalition’s answer to timing: “Payers have their own procedures and timelines for implementing new codes, so providers must obtain that information from each payer with whom they work,” preferably in writing before January 1, 2027 (supplemental guidance, p. 29). Its provider guide lists what to ask: when the codes load in the claims system, the payer’s crosswalk, the rate for each new code, whether current authorizations convert, how claims spanning the transition are handled and the notification date (Preparing for implementation, p. 2). Ask your Optum provider relations advocate those questions, and see the 2027 crosswalk for its dated payer tracker. We update this section when Optum publishes.

What is Optum’s rendering provider NPI and taxonomy rule?

From 2026, “all behavioral health claims for members covered by a Commercial (employer-sponsored) health plan must include the National Provider Identifier (NPI) and taxonomy code(s) for both the billing provider and the rendering provider,” validated against NPPES; “Claims that are missing this information will be rejected or denied” (Optum Top of Mind, September 2025). Optum ran informational edits from October 2025 and said “The effective date will be announced in Q1 2026.” We could not find that announcement on Provider Express on October 29, 2026, so confirm the date with Optum.

Where the data goes, per the same notice:

• Electronic claims: “The NPI and taxonomy are submitted in the 2310 and 2420 loops of either EDI 837P (Professional) or EDI 837I (Institutional).”
• Paper professional claims: boxes 24J and 24I.
• When to list a rendering provider: “Rendering provider information is required when it’s different from the billing provider.”

The behavior analyst taxonomy code is 103K00000X (NUCC taxonomy); check each clinician’s NPPES record (NPI Registry) so the taxonomy on the claim matches it. Whether Optum expects an RBT’s own NPI as the rendering provider on 97153 lines is not stated in the policy, so ask Optum (our reading).

How does Optum’s policy affect ABA documentation and session notes?

The claim has to match the note. Each note should name the person who delivered the service, their credential (so the modifier matches) and, if they are listed as the rendering provider, their NPI. For a BCBA’s 97155 time, the note should show which technician was working and the technician’s code, because Optum allows 97153 or 97154 with 97155 only when both descriptors are met and the two are different people (Q&A 7). For 97155 and 97156 on one day, record separate start and stop times, since Optum denies claims where “documentation does not clearly separate the 2 services” (Q&A 11).

From January 1, 2027, the note also decides the code: a BCBA treating with no technician present is 97173, not 97155, and data review without the client is 97180, if Optum adopts the codes. For note elements, see the 97155 documentation guide and the 97180 log.

Optum ABA claim checklist

Run this before each commercial batch:

• Billing NPI and taxonomy, and rendering NPI and taxonomy when different, in the 2310/2420 loops (or boxes 24I/24J).
• Every NPI and taxonomy matches NPPES.
• One provider-level modifier per line, matching the credential of the person who delivered the service (HM, HN, HO or HP).
• Units counted by the 8-minute rule and within Optum’s daily limits (97153: 32 units).
• 97155 lines have a concurrent technician line by a different person; 97155 and 97156 on the same day have separate times.
• No 97153 or 97155 billed for technician training or treatment planning.
• For dates of service from January 1, 2027: no 0362T or 0373T, and new codes billed only after Optum confirms it has loaded them.

Sources

• Optum. Applied Behavior Analysis (ABA) Reimbursement Policy - Commercial, policy 2022RP501A (history: February 2026 update; Q&A 12 and 13 added June 2026). Checked October 29, 2026.
• Optum Provider Express. Rendering provider NPI & taxonomy will be required on all Commercial claims in 2026 (Top of Mind, September 2025).
• ABA Coding Coalition. Supplemental guidance on the 2027 codes (published October 2026); Preparing for implementation (October 2026).
• National Uniform Claim Committee. Health Care Provider Taxonomy code set; CMS NPI Registry.

This page is billing information, not legal advice, and it is not affiliated with Optum. Check your contract and Provider Express before you bill. CPT is a registered trademark of the American Medical Association.

Updated October 29, 2026: rebuilt around Optum’s commercial ABA reimbursement policy (modifiers, daily limits, Q&As) and its 2027 status. Corrected: Optum’s notice puts NPI and taxonomy in the 2310 and 2420 loops, it had not set an enforcement date in the notice, and 97155 is not the parent training code (that is 97156).

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