90834 vs. 90837: Which Therapy CPT Code Should You Use

The Actual Time Thresholds for 90834 and 90837

CPT 90834 applies to sessions lasting 38–52 minutes of direct clinical contact. This covers the commonly referenced 45-minute session format.

CPT 90837 covers sessions of 53 minutes or longer. You don't need a full 60 minutes; 53 minutes qualifies for this code.

CPT 90832 exists for shorter sessions (16–37 minutes), though outpatient practices rarely use it.

The critical distinction: a 50-minute session falls within the 90834 range, not 90837. Only face-to-face clinical time counts — administrative tasks like copay collection, scheduling follow-ups, and post-session documentation don't factor into session duration.¹ For a broader overview of how behavioral health billing handles time-based codes, the rules apply consistently across the major psychotherapy CPT codes.

What Your Notes Need to Show for Each Code

Documentation must include start and stop times directly in the clinical note.² Format like "Session: 2:05 PM to 2:55 PM (50 minutes)" provides clear, auditable documentation.

For 90834, standard therapy notes suffice: interventions, client response, and progress toward goals.

For 90837, payers expect expanded justification. Documentation should reference: active risk assessment, trauma processing, emotional dysregulation, crisis support, or complex co-occurring diagnoses. Simply noting "session ran long" lacks clinical support.

CPT 90837 receives more audit scrutiny than other psychotherapy codes.³ Claims lacking start/stop times are vulnerable to retroactive downcoding — one of the more common reasons practices see their clean claim rate fall without an obvious explanation.

Why Undercoding Costs You Just as Much as Upcoding

Medicare reimburses approximately $154 for 90837 versus $98 for 90834 — a $56 difference per session.⁴

A therapist with 20 weekly clients consistently undercoding can lose over $900 monthly in legitimate revenue.⁵ Annually, this represents more than $10,000 in unrecovered payments. Tracking this kind of pattern is part of what revenue cycle management oversight catches when billing is reviewed systematically.

Undercoding often stems from fears about attracting audits, but accurate billing with proper documentation is defensible. Trauma-focused work, couples therapy, family sessions, and crisis interventions naturally require extended time and justify 90837 billing.

One group practice discovered three providers running 55-minute sessions but defaulting to 90834. Correcting the coding recovered approximately $2,700 monthly without adding clients. This is the kind of issue that shows up when practices review their billing KPIs and compare reimbursement per session against expected rates.

Not All Insurance Plans Cover 90837 the Same Way

Commercial payers handle 90837 differently than Medicare. Some restrict it to specific diagnoses, require prior authorization, cap annual usage, or silently downcode claims without notification.

Benefits verification before initial sessions reveals plan-specific restrictions and reimbursement rates. When documentation supports 90837 billing but claims return downcoded, appeals with supporting evidence can recover underpayments. Patterns of silent downcoding are also a form of claim denial worth tracking systematically.

One Minnesota practice targeting a UCare pattern of silent downcoding recovered full payment on six months of previously underpaid claims through documented appeals.

Final Thoughts

The guideline is straightforward: 38–52 minutes = 90834; 53+ minutes = 90837. Both require documented start/stop times.

Success requires consistent documentation practices, monitoring for payer downcoding patterns, and verifying individual contract terms. Working with a behavioral health billing partner who monitors code patterns monthly and flags discrepancies prevents revenue leakage before it compounds. If you're ready to address coding gaps in your practice, get started with a free assessment.

Footnotes

1. CPT Code Time Requirements for Psychotherapy Codes 90832, 90834, 90837 — TherapyNotes, 2024

2. CPT 90837 vs. 90834: Billing Psychotherapy Without Losing RVUs — InfoHub Consultancy, 2024

3. Upcoding or Downcoding: Psychotherapy Billing Risk — TheraPlatform, 2024

4. CPT Code 90837: 60 Minute Individual Therapy with Reimbursement Rates — TheraTHINK, 2026

5. CPT 90837 vs. 90834: Billing Psychotherapy Without Losing RVUs — InfoHub Consultancy, 2024