CPT Code 90837: The Complete Billing Guide for 60-Minute Psychotherapy Sessions

Documentation requirements, Medicare reimbursement, and audit triggers — what independent therapists need to know about the most scrutinized psychotherapy code.

CPT code 90837 is used to bill for psychotherapy sessions lasting 53 minutes or longer. It is the highest-reimbursing of the three individual psychotherapy time-based codes, and it is also the one most likely to trigger a Medicare audit or a commercial payer utilization review.

If you are a Licensed Clinical Social Worker (LCSW), Licensed Professional Counselor (LPC), or Licensed Marriage and Family Therapist (LMFT) billing Medicare, understanding when and how to use 90837 correctly is one of the most important parts of protecting your practice from denials and audit risk.

What 90837 actually means

The CPT description for 90837 is “Psychotherapy, 60 minutes with patient.” In practice, that means the session must include at least 53 minutes of psychotherapy with the patient present. The 53-minute floor exists because CPT time-based codes round to the nearest reportable unit — 90837 is reportable once the 53-minute threshold is met.

Sessions lasting 38 to 52 minutes are billed under 90834. Sessions of 16 to 37 minutes are billed under 90832. Sessions under 16 minutes of psychotherapy are generally not reportable as psychotherapy at all.

Time thresholds you have to know

Your documentation must support the time you billed. CMS guidance indicates that time-based codes require explicit documentation of the start and stop time of the therapy component, or the total face-to-face time spent in psychotherapy. Session notes that say only “60-minute session” without supporting time detail are a common audit finding.

Why 90837 triggers audits

Multiple Medicare contractors and commercial payers use billing frequency of 90837 as an audit flag. Therapists who bill 90837 for a high percentage of their sessions — for example, over 80 percent of encounters — are more likely to be selected for documentation review than therapists whose code distribution reflects a mix of 90832, 90834, and 90837.

The OIG has noted that the shift toward 90837 as a default has been significant since it was introduced as a separate code in 2013, and that high-utilization therapists have been a focus of post-payment review. This does not mean you should avoid billing 90837 when the session warrants it. It means your documentation must consistently support the time billed, and your overall billing pattern should reflect the actual mix of session lengths in your practice.

Documentation that holds up

A defensible 90837 note generally includes:

• Date of service and the explicit start and stop time of the therapy component (e.g., “therapy 10:04a–11:04a, total 60 minutes”)
• Active diagnosis supporting medical necessity for psychotherapy at the billed length
• Specific therapeutic interventions used during the session (CBT techniques, EMDR protocol phases, DBT skills, psychodynamic interpretations, etc.) — not just general descriptors like “supportive therapy”
• Patient response to the interventions, including measurable or observable changes in affect, insight, symptom expression, or behavior
• Connection to the treatment plan — how the session moved the patient toward documented goals
• Plan for the next session, including any homework or between-session tasks

Medicare reimbursement for 90837

Medicare reimbursement for 90837 varies by locality and by the provider type rendering the service. LCSWs historically received 75 percent of the physician fee schedule rate for behavioral health services until that parity gap was addressed in recent rulemaking. LMFTs and LPCs became eligible Medicare providers on January 1, 2024, at the same reimbursement parity as LCSWs.

Because rates change with each annual Medicare Physician Fee Schedule, and because locality adjustments vary, the practical answer is to check the current year’s published fee schedule for your MAC jurisdiction. Most MACs publish an annual locality-specific fee lookup tool.

Common 90837 denials and how to avoid them

Medical necessity not documented

The most common 90837 denial is for medical necessity. Medicare requires that the longer session length be clinically justified, not a default. If your documentation does not connect the 60-minute length to the patient’s clinical complexity, diagnosis severity, or treatment protocol requirements, the claim is at risk.

Time not adequately documented

Notes that say “session ran 60 minutes” without a start/stop time or total face-to-face therapy time are frequently flagged. The fix is consistent time documentation on every note.

Billing 90837 for a session that included E/M

If you are a psychiatrist or other prescriber billing an evaluation and management (E/M) code alongside psychotherapy, the psychotherapy component must be documented separately, with its own start/stop time distinct from the E/M portion. The two components cannot overlap.

Frequency patterns

Billing 90837 as a near-universal default is a pattern risk. Your documentation must support the length, and your population must support the mix. Consistent appropriate use of 90832 and 90834 where clinically warranted strengthens your overall billing profile.