90837 vs. 90834: Which Therapy CPT Code Should You Bill?

If you run a therapy practice, the choice between 90837 vs. 90834 probably shows up on nearly every claim you submit — and it’s one of the easiest places to lose revenue without realizing it. Bill 90834 for a 60-minute session and you leave roughly a third of the reimbursement on the table. Bill 90837 for every session regardless of length and you invite payer audits that claw back thousands. Getting this right is a core part of sound medical billing services for behavioral health, and it starts with the time thresholds.

Here’s the practical, 2026-accurate breakdown: what each code means, exactly what documentation each requires, the denial triggers that cost therapy practices the most, and how telehealth modifiers pair with each code.

What Do 90834 and 90837 Actually Mean?

Both codes describe individual psychotherapy with the patient (and/or family member). The difference is session length:

• CPT 90834 — Psychotherapy, 45 minutes with patient. Reportable when the session lasts 38 to 52 minutes.
• CPT 90837 — Psychotherapy, 60 minutes with patient. Reportable when the session lasts 53 minutes or longer.

The rule is “closest to, past the halfway mark”: a 45-minute session clears the 38-minute threshold for 90834, and a 60-minute session clears the 53-minute threshold for 90837. (For reference, 90832 covers 30-minute sessions of 16–37 minutes.) Note the thresholds, not the face-time labels — a “45-minute session” that runs 55 minutes should be coded 90837, and a “60-minute session” that ends at 50 minutes is 90834.

90837 vs. 90834: The Time Thresholds Side by Side

That ~$50 gap is why the code choice matters financially. A therapist seeing 25 patients a week who routinely downcodes 60-minute sessions to 90834 loses roughly $1,250 per week — over $60,000 a year. But the gap also explains why payers scrutinize 90837 heavily, which brings us to documentation.

What Documentation Does Each Code Require?

The documentation requirements are the same for both codes, but the stakes are higher for 90837 because payers audit it more often. Every therapy note should include:

1. Start and stop times. This is the single most important element for 90837. Many payers (and all Medicare auditors) want to see exact times proving the session reached 53+ minutes. Duration stated as “60-minute session” without timestamps is weaker evidence.
2. Medical necessity. The diagnosis, the severity, and why the session length was clinically appropriate. For 90837, a brief line explaining why the full hour was needed (e.g., complex trauma processing, safety planning) strengthens the record.
3. Intervention and modality. What therapeutic techniques were used (CBT, EMDR, DBT, etc.) and how they relate to the treatment plan.
4. Patient response and progress. How the patient responded and whether progress toward treatment goals was made.
5. Updated treatment plan. Especially for longer or ongoing courses of treatment — the plan should justify continued sessions at the billed length.

Practical tip: build a note template that auto-prompts for start/stop times and a one-line “why this length” field. Practices that standardize this see far fewer 90837 denials on review.

Why Do 90837 and 90834 Claims Get Denied?

Four patterns account for most therapy-code denials — and most are preventable:

1. 90837 overutilization flags. This is the big one. Medicare and several commercial payers flag providers who bill 90837 for an unusually high share of sessions (commonly cited around 50%+). If your clinical reality genuinely supports it, document it — but if most of your sessions are 45 minutes and you’re defaulting to 90837, that’s upcoding exposure.
2. Session length doesn’t support the code. A 90837 billed for a 48-minute session will be denied or downcoded on review. Timers drift; if your scheduling blocks are “45 minutes,” make sure the actual time clears 38 minutes, not 35.
3. Medical necessity challenges. Denials under CO-50 (non-covered service, not deemed medically necessary) hit 90837 more often, especially when notes are thin. The longer the session, the more the note must justify it.
4. Same-day duplicates. You cannot bill 90834 and 90837 for the same patient, same provider, same day. If a patient legitimately has two separate sessions, only one psychotherapy code is payable — plan schedules accordingly.

Denial rates run higher in behavioral health than in most specialties. If denials are a recurring problem, see our guide to behavioral health claim denials and the 7 fixes for therapy practices.

Can You Bill 90837 and 90834 for Telehealth?

Yes — both codes are fully billable via telehealth, and the time thresholds are identical. What changes is the modifier and place-of-service coding:

• Modifier 95 — the standard telehealth modifier for most commercial payers. (Some payers still accept GT; always verify the specific payer’s policy.)
• Place of service: POS 02 (telehealth, patient not at home) or POS 10 (telehealth, patient at home). Using the wrong POS is a common denial trigger — POS 11 (office) with a telehealth modifier will reject.
• Audio-only note: Medicare requires an in-person visit within 6 months before starting mental-health telehealth and annually thereafter, with documented exceptions. Keep this in your intake workflow if you bill Medicare.

Start/stop times matter even more for telehealth, since there’s no office-visit record to corroborate duration. Your EHR or video platform timestamps should match the note.

FAQs

Can I bill 90837 for a 50-minute session?

No. The threshold for 90837 is 53 minutes or longer. A 50-minute session falls in the 38–52 minute range and must be billed as 90834. Billing 90837 below the threshold is upcoding, even if your schedule calls it a “60-minute slot.”

What happens if I bill 90837 for every session?

Payers routinely flag providers whose 90837 share is disproportionate (often cited around 50%+ of sessions). Expect medical-record requests, downcoding, and possible recoupment. Only bill 90837 when sessions genuinely last 53+ minutes and the notes prove it.

Can 90837 be billed with add-on codes?

Yes. The interactive-complexity add-on (+90785) can be appended to 90837 (and 90834) when specific complexity factors complicate delivery of the psychotherapy, such as managing maladaptive communication or caregiver involvement. It requires its own documentation.

Is 90834 or 90837 better for telehealth?

Neither is “better” — the code follows session length, not modality. Use modifier 95 and the correct place of service (02 or 10). The reimbursement difference between the two codes applies the same way on telehealth claims.

Which code pays more, 90834 or 90837?

90837 pays roughly 50% more — around $150 vs. around $100 under 2026 Medicare national averages, varying by locality and payer. The difference reflects the 3.00 vs. 2.00 work RVUs.

Next Steps: Get a Behavioral Health Billing Review

The 90837 vs. 90834 decision looks small, but multiplied across hundreds of sessions it’s one of the highest-leverage coding choices in a therapy practice — and one of the most audited. If your 90837 rate is high, your denials are climbing, or you’re not sure your notes would survive a payer review, get a second set of eyes before an auditor forces the issue.

Request a free behavioral health billing review — we’ll check your code mix, denial patterns, and documentation against what payers actually require.