Coding · July 11, 2026 · 5 min read

CPT Code 90834: The 45-Minute Psychotherapy Code, Explained

CPT 90834 is the workhorse of outpatient mental health billing — the 45-minute individual psychotherapy code that most "therapy hour" sessions actually map to. It's also the code at the center of the most common coding decision in behavioral health: 90834 or 90837? Here's how to bill it correctly.

What CPT 90834 covers

90834 is individual psychotherapy with the patient (and/or a family member) when documented face-to-face time is 38 to 52 minutes. A traditional 45- or 50-minute therapy session lands here. Like the other timed psychotherapy codes, it can be billed by any licensed psychotherapy provider — psychologists, LCSWs, LPCs, LMFTs, psychiatrists, and psychiatric NPs.

Time thresholds at a glance

The classic 50-minute hour is a 90834 — not a 90837. 53 documented minutes is the line.

90834 vs 90837: the decision that matters

The gap between 90834 and 90837 is one of the biggest recurring revenue decisions in a therapy practice: 90837 typically reimburses 20–30% more, but requires 53+ documented minutes and draws more payer scrutiny. Neither code is "safer" in the abstract — the safe code is the one your documented time supports. We break down the full comparison, audit risk, and payer behavior in 90837 vs 90834.

Documentation requirements

• Session time — start/stop or total minutes, every session.
• Interventions and response — modality used and clinical progress.
• Treatment plan linkage — symptoms addressed and plan going forward.

Common denials and how to avoid them

• Undocumented time — the top audit finding on timed codes.
• Same-day service conflicts — psychotherapy plus other same-day behavioral services can trigger edits without the right modifier.
• Telehealth coding errors — 90834 is broadly telehealth-eligible, but payer-specific modifier and POS rules still apply.
• Authorization lapses — most payers don't require auth for 90834, but plans that do will deny every session past the approved count. See prior authorization in behavioral health.

Full code family: behavioral health CPT reference. Bigger picture: the complete mental health billing guide.

This guide is for general reference only. CPT codes, HCPCS codes, and payer rules change, always verify against current coding guidance and your specific payer policies. CPT is a registered trademark of the American Medical Association.