90834 vs 90837: How to Bill Psychotherapy by Time

Both codes report individual psychotherapy, insight oriented, behavior modifying and/or supportive, face-to-face with the patient. They are time-based codes, so the documented session length — not the diagnosis, technique, or complexity — determines which one you bill.

The single rule that drives everything: psychotherapy CPT codes are reported using the midpoint (one-half) rule. Once the face-to-face time passes the lower threshold of a code, that code is the correct one until you reach the next code's threshold. So 37 minutes is a 90832, 38 minutes becomes a 90834, and the moment you document 53 minutes it becomes a 90837. There is no code for sessions under 16 minutes — that time is not separately reportable as psychotherapy.

In our mental-health billing audits we typically see the largest avoidable revenue leak not in denials but in systematic downcoding: clinicians running genuine 53-plus-minute sessions but billing 90834 out of caution, leaving money on the table on every visit. Accurate time documentation fixes both directions of the error.

The most common point of confusion is why a '45-minute' code starts at 38 minutes. The answer is the CPT midpoint rule for time-based services: you select the code whose typical time the actual session is closest to, and the boundary sits at the midpoint between two codes' typical times.

• The midpoint between the 30-minute code (90832) and the 45-minute code (90834) is 37.5 minutes, so 38 minutes is the floor for 90834.
• The midpoint between the 45-minute code (90834) and the 60-minute code (90837) is 52.5 minutes, so 53 minutes is the floor for 90837.

That produces the canonical psychotherapy time grid:

There is no upper cap on 90837. A 75-minute or 90-minute standard outpatient session is still reported with a single 90837 — you do not stack units, and there is no separate prolonged-psychotherapy add-on for routine sessions (the crisis code 90839/90840 is a different service with its own rules). Only the time spent face-to-face delivering psychotherapy counts. Time spent on documentation after the patient leaves, coordinating care, or completing forms does not extend the session for code selection.

Reimbursement for both codes is set, for Medicare, by the CMS Physician Fee Schedule (PFS): each code carries a total RVU value that is multiplied by the annual conversion factor and adjusted by your locality's GPCI. Because the geographic adjustment changes the dollar amount in every locality, there is no single national 90834 or 90837 number that applies to your practice — the exact allowable varies by MAC and locality, so verify your locality on the CMS PFS Look-Up Tool.

What is consistent nationally is the relationship between the codes and the RVU basis behind them:

Two operational takeaways:

1. 90837 pays materially more than 90834 — typically on the order of 25-35% more per session at the CMS allowable, and proportionally more under commercial contracts that benchmark to Medicare. Across a full caseload, the difference between correctly billing 90837 and defensively downcoding to 90834 is one of the largest single levers on a therapist's annual collections.
2. Commercial payer rates are contract-specific. Many commercial plans set behavioral-health rates as a percentage of the Medicare PFS, but the multiplier and any carve-outs are negotiated — check your fee schedule rather than assuming parity. Some plans historically reimbursed 90834 and 90837 at a smaller spread than Medicare does, which changes the downcoding math in your market.

For a deeper look at why these revenue gaps persist in behavioral-health practices, see why mental health practices lose revenue in billing.

Because 90837 is the higher-paying code, it is the one payers downcode or request records on. The defense is documentation that proves the session genuinely met the 53-minute floor and was medically necessary. Every 90837 note should contain:

1. Total time, or start and stop times. The single most important element. "Session 55 minutes" or "3:00 PM-3:58 PM" removes any ambiguity about the time threshold. A note that never states the duration is the easiest 90837 for a payer to downcode to 90834.
2. Medical necessity for the longer session. Tie the length to clinical need — acuity, complexity, trauma processing, a treatment modality (e.g., prolonged exposure, EMDR) that requires a full hour, or risk factors that warranted extended engagement. "Routine" 60-minute sessions for low-acuity presentations are exactly what utilization reviewers look for.
3. A current diagnosis that supports ongoing psychotherapy. The ICD-10 mental-health diagnosis must be active and consistent with the treatment plan.
4. Substantive clinical content matching the time. Interventions delivered, patient response, progress against treatment-plan goals. A one-paragraph note attached to a 60-minute claim invites scrutiny.
5. Consistency across the record. If your schedule shows back-to-back 30-minute slots but your claims show 90837, the calendar contradicts the code. Align scheduling, the EHR timer, and the billed code.

Why payers target 90837: several major commercial payers have, in past cycles, sent letters to clinicians whose 90837 utilization sat well above peer norms, and some have applied prepayment review to high-90837 providers. The code is fully billable when earned — the lesson is not to avoid 90837, but to document it so it survives review. A clinician whose notes consistently state total time and tie length to medical necessity has nothing to fear from a records request.

When a psychiatrist, psychiatric NP, or other prescriber performs both an evaluation-and-management (E/M) service and psychotherapy in the same visit, the psychotherapy is reported with a time-based add-on code, not the standalone 90834/90837. The E/M code is selected first (by medical decision-making or total time), then the add-on is layered on for the psychotherapy portion:

Key rules for the add-on combination:

• The add-on (90833/90836/90838) is never billed alone — it must accompany a payable E/M code on the same claim.
• The time used for E/M and the time used for psychotherapy must be separately identifiable. You cannot count the same minutes toward both. The note should distinguish the medical/medication-management portion from the psychotherapy portion.
• This combination is what allows prescribers to capture both the medication-management value and the therapy value of a single visit — a frequent under-coding gap when prescribers default to an E/M code alone.

Non-prescribing therapists (LCSWs, LPCs, LMFTs, psychologists) who do not perform E/M services bill the standalone 90834 or 90837 and do not use the add-on codes.

Individual psychotherapy is one of the most-delivered telehealth services, and both 90834 and 90837 are on Medicare's list of telehealth-eligible behavioral-health codes. The time rules do not change for telehealth — a 53-minute video session is still a 90837. What changes is the administrative layer:

• Place of service (POS). Telehealth claims use a telehealth POS rather than POS 11 (office). The correct telehealth POS affects whether the claim pays at the facility or non-facility rate, so it directly impacts the allowable. Confirm the current payer requirement before the claim goes out; mismatched POS is a common, avoidable behavioral-health denial.
• Telehealth modifier. Payers generally require a telehealth modifier (commonly 95 for synchronous audio-video). The modifier requirement and the accepted POS vary by payer and have shifted across regulatory cycles, so verify each payer's current rule rather than assuming.
• Audio-only. Some plans permit audio-only psychotherapy with a specific modifier; many do not, or pay it differently. Do not assume audio-only is payable at the same rate.
• Documentation. Note that the service was rendered via telehealth, the modality (audio-video vs audio-only), patient location, and — as always for 90837 — the total time.

Getting the POS and modifier combination right is where most telehealth psychotherapy denials originate. For the broader playbook, see our guide to telehealth medical billing.

Psychotherapy claims hit a predictable set of denials. Most trace back to time documentation, payer authorization rules, or POS/modifier setup rather than the code choice itself.

Prevention beats appeals on these. Verifying behavioral-health eligibility and authorization before the first session, embedding a total-time field in the EHR note template, and reconciling POS/modifier on every telehealth claim eliminate the majority of 90834/90837 denials before they happen. When the backlog already exists, structured denial management services can work the authorization and downcode denials and feed the patterns back into prevention.

A practice billing 90834 and 90837 cleanly does five things consistently:

1. Every note states total time or start/stop times. This is the foundation for accurate code selection in both directions — it prevents over-coding that fails audit and under-coding that loses revenue. Build a required time field into the EHR template.
2. Code selection follows the time grid mechanically. 16-37 = 90832, 38-52 = 90834, 53+ = 90837. Train clinicians on the midpoint rule so the code matches the documented minutes instead of habit.
3. 90837 is billed when earned and documented to survive review. The answer to elevated payer scrutiny is documentation quality, not defensive downcoding. Tie session length to medical necessity.
4. Eligibility, behavioral-health authorization, and visit limits are checked before the session. Authorization denials (CARC 197) and carve-out filing problems are almost entirely preventable at the front end. See our prior authorization process breakdown.
5. Telehealth POS and modifier are reconciled on every remote claim. The single most common avoidable telehealth psychotherapy denial is a POS/modifier mismatch.

Practices that operationalize these disciplines recover the revenue lost to systematic downcoding and cut psychotherapy denials substantially. If your team lacks the bandwidth to run eligibility, authorization, and denial follow-up alongside a full clinical schedule, outsourced mental health billing services or behavioral health billing services can own the full revenue cycle end to end.