CPT 90791: Psychiatric Diagnostic Evaluation

Mukesh MakwanaFounder & CEO · 8+ years hands-on in medical billing & RCM · Reviewed September 29, 2026

CPT 90791 opens most behavioral health episodes, which means an error in how it is coded repeats at the front of every new patient relationship. The code itself is simple. What catches practices out is everything 90791 will not sit next to on a claim, and how rarely a payer will pay it twice.

What CPT 90791 covers

90791 is the psychiatric diagnostic evaluation: an integrated biopsychosocial assessment including history, mental status and recommendations. It is the evaluation without medical services.

Its counterpart is 90792, the same evaluation with medical services. The dividing line is whether medical services were part of the evaluation, typically a physical examination element or the prescribing decisions a physician or other prescriber makes. A non-prescribing clinician bills 90791. A prescriber who performs medical services bills 90792. The two are never billed together: Medicare's edits pair them with a modifier indicator of 0.

90791 is not a time-based code. There is no minute threshold to hit and no add-on for a longer evaluation. What supports it is the completeness of the assessment, not its length.

The rule that drives most 90791 denials

The NCCI policy manual states it plainly: because psychotherapy includes continuing psychiatric evaluation, 90791 and 90792 are not separately reportable with individual, group, family, crisis or other psychotherapy codes for the same date of service.

The manual is equally direct about evaluation and management services: E/M codes such as 99202 to 99215 shall not be reported with either diagnostic psychiatric code. A prescriber who wants to bill an E/M for the initial visit should be billing 90792 or an E/M, not 90791 plus an E/M.

The practical consequence is a scheduling decision, not a coding decision. Practices that routinely run an intake and a first therapy session back to back on day one are choosing to give one of them away. Splitting them across two dates makes both billable.

How often 90791 will pay

Medicare's medically unlikely edit for 90791 is one unit per patient per day, and the rationale CMS records for it is the code descriptor and CPT instruction rather than a clinical judgement. Beyond that daily limit, frequency is payer policy rather than a national rule, and it varies widely:

• Most commercial payers expect one evaluation per patient per clinician per episode of care.
• Many will pay a second evaluation after a defined gap, commonly six or twelve months, or on a documented change in condition.
• A different clinician in the same group frequently does not get a fresh evaluation paid, because the payer treats the group as one provider.
• Medicaid programmes often impose their own annual limit and their own modifier requirements.

Because none of this is national policy, the only reliable approach is to record the rule per payer and check it before the intake is scheduled rather than after the claim rejects.

Documentation requirements

• A complete history: presenting problem, psychiatric history, substance use, medical history, developmental and social history, and family history.
• A mental status examination with the elements actually assessed, not a template with everything marked normal.
• Risk assessment, including suicide and violence risk, and what was done about what was found.
• A diagnosis with the reasoning that supports it, not a code dropped at the end.
• Recommendations and an initial treatment plan, including the modality and frequency proposed.
• Any communication with family or other informants, and any records reviewed.
• Where the evaluation was by telehealth, the modality and both locations.
• The clinician's signature and credentials, which is a routine rejection reason on intake claims from group practices.

Common denials and the exact fix

Modifier rules

• 95: synchronous telehealth by real-time audio and video, the standard on Medicare professional claims.
• 93: synchronous telehealth by audio only, which behavioral health may use.
• GT: the legacy audio and video modifier, retired for Medicare professional claims and now largely confined on the Medicare side to Critical Access Hospital Method II institutional claims. Several state Medicaid programmes and older commercial contracts still ask for it on an intake delivered by telehealth. Confirm which one each payer wants before the first remote intake rather than after it denies.
• 59, XE, XP, XS, XU: will not release the psychotherapy or E/M pairs, which carry a modifier indicator of 0. Using them on those pairs is a compliance problem, not a workaround.
• AJ, AH, and the state Medicaid H-series modifiers: identify clinician type or programme where a payer requires it on the line.
• No 26 or TC: CMS gives 90791 a PC/TC indicator of 0, so component modifiers never apply.
• Place of service: 11 for an office intake, 10 where the patient was at home on telehealth, and 02 for telehealth from anywhere else. The non-facility rate applies to the patient's home, which matters because the gap between the two settings on this code is not small.

Interactive complexity with the evaluation

90785 may be added to a diagnostic evaluation where a specific communication factor made the encounter harder: a patient who has not developed the expressive language to describe symptoms, a caregiver whose involvement complicates the assessment, or a mandated report arising during the encounter. Name the factor in the note. Medicare does not accept 90785 billed solely for interpretation or translation.

NCCI bundling edits

From the Medicare practitioner procedure-to-procedure file effective October 1, 2026. Indicator 0 means no modifier will release the pair.

• 90791 with 90832, 90834, 90837, 90833, 90836, 90838, 90839, 90840, 90845, 90846, 90847, 90849, 90853, 90865 or 90880: indicator 0 across the whole psychotherapy family.
• 90791 with 99202 to 99215: indicator 0.
• 90792 with 90791: indicator 0.
• 90791 with 96116: indicator 0.
• 90791 with 90867, 90868, 90869 or 90870: indicator 0.
• 90791 with 96156, 96158, 96159, 96164 or 96167: indicator 0.
• 90791 with 97151, 97153, 97155 or 97156: indicator 0.
• 90791 with 96127: indicator 0.
• 90791 with G0396, G0397, G0442, G0443 or G0444: indicator 1, so a screening or intervention may be separately reportable where its time and work were genuinely distinct from the evaluation.

Local coverage: is there an LCD for this code?

There is no national coverage determination for psychotherapy or psychiatric evaluation, so coverage is set locally and it differs by jurisdiction. Several Medicare Administrative Contractors publish a local coverage determination for psychiatric services together with a billing and coding article that carries the actual code list. Novitas Solutions, for example, maintains LCD L35101 (Psychiatric Codes, effective January 1, 2024) with billing and coding article A57130, which is where the covered CPT and HCPCS codes and the covered diagnoses actually live.

Two practical consequences. First, the diagnosis list that supports CPT 90791 in one jurisdiction may not support it in another, so the article to read is the one from the contractor that processes your claims. Second, LCDs and their articles are revised without much notice, which is why a claim that paid last quarter can deny this quarter with nothing changed on your side. Search the CMS Medicare Coverage Database by code and by your contractor, and re-check it when a denial pattern appears.

What CPT 90791 pays

90791 is paid as a whole service with no component split, and it carries more work value than a 45-minute therapy session, which is why an intake that gets miscoded as psychotherapy is an expensive error rather than a cosmetic one. Medicare publishes relative values rather than a price; run your own locality through the CMS look-up tool linked below to get the figure that applies to you.

2026 Medicare RVUs for CPT 90791

Source: CMS CY 2026 PFS Relative Value File, RVU26D (October release, published 08/26/2026). RVUs are national and unadjusted; commercial and Medicaid payers set their own rates and their own coverage.

In the 2026 CMS relative value file, CPT 90791 carries 3.84 work RVUs, with 5.19 total RVUs in a non-facility setting and 4.11 in a facility. The gap is practice expense: in an office the practice carries it, in a facility the facility does. Its PC/TC indicator is 0: CMS treats it as a physician service, so modifiers 26 and TC do not apply to it in any setting. Its global indicator is XXX: the surgical global period concept does not apply, so there is no postoperative period bundling other services into it. Across the diagnostic evaluation codes, work RVUs run from 3.84 (90791) to 4.16 (90792), so 90791 carries the lowest physician work in its group.

Units per day. Medicare's medically unlikely edit allows 1 unit of CPT 90791 per patient per day (a date of service edit set on clinical grounds, rationale: code descriptor / CPT instruction). A second unit on the same date will not pay. MUE values are published quarterly in the Medicare NCCI practitioner services MUE table; the value above is from the table effective October 1, 2026.

To turn RVUs into payment, each component is multiplied by your locality's geographic practice cost index, the three are added, and the sum is multiplied by the 2026 conversion factor: $33.4009, or $33.5675 for qualifying APM participants (CMS-1832-F; CMS fact sheet). The CMS Physician Fee Schedule Look-Up Tool runs that calculation for your own locality.

Frequently asked questions

Sources

American Medical Association, CPT 2026 Professional Edition.
Centers for Medicare & Medicaid Services, CY 2026 PFS Relative Value File RVU26D (October release, published 08/26/2026): RVUs, PFS status indicator, PC/TC indicator and global indicator for 90791.
Centers for Medicare & Medicaid Services, CY 2026 Physician Fee Schedule final rule, CMS-1832-F: conversion factors.
Centers for Medicare & Medicaid Services, Medicare NCCI Practitioner Services medically unlikely edit table, effective October 1, 2026.
Centers for Medicare & Medicaid Services, Medicare NCCI procedure-to-procedure edits for practitioner services, 2026 Q4 file effective October 1, 2026.
Centers for Medicare & Medicaid Services, Medicare Coverage Database: Novitas Solutions local coverage determination L35101 (Psychiatric Codes, effective 01/01/2024) and billing and coding article A57130.
Centers for Medicare & Medicaid Services, National Correct Coding Initiative Policy Manual for Medicare Services, revision date 1/1/2026, Chapter XI (Medicine), Section C, Psychiatric Services.

CPT® is a registered trademark of the American Medical Association. Payer policy, NCCI edits and MUE values change quarterly, so check your own contractor and your commercial contracts before submission. How we verify this guidance.

Related codes

• CPT 90837. The 60-minute psychotherapy code that most often follows the evaluation, and cannot share its date.
• CPT 99492. Collaborative care, where behavioral health assessment is billed monthly by the treating practice.

Related reading

• Behavioral health & psychiatric billing. How we scrub session-based claims, track prior authorization and bill collaborative care.
• Provider credentialing & payer enrollment. A behavioral health claim only pays in network once the clinician is enrolled and effective.
• Behavioral health prior authorization in 2026. Why authorizations lapse mid-episode and what catching them early is worth.
• 2026 behavioral health code changes. What the CY 2026 fee schedule changed for collaborative care, digital mental health and telehealth.