CPT Code 90837: How to Document Medical Necessity

Billing for a 90837 session can bring up uncertainty. You want to be compensated fairly for your time, especially when a session requires more intensive work, but you may also worry about attracting unwanted scrutiny from payers. Because 90837 reimburses at a higher rate than 90834, payers often flag this code for review.

The following documentation best practices are designed to give you confidence, helping you create clear, defensible documentation that justifies the medical necessity of the longer session and protects your practice.

The Medicare Rule

Historically, CPT has labelled 90837 as “60 minutes of psychotherapy.” But when it comes to insurance billing and reimbursement, Medicare sets the standard for session length.

Session lengths, according to CMS/Medicare:

• 90834 = 38-52 minutes of psychotherapy
• 90837 = 53 minutes or more of psychotherapy

CMS states: “Report the code closest to the actual time: 38-52 minutes for 90834… and 53 or more minutes for 90837.”

This is why 90837 is referred to as “extended.” It is not a judgment on clinical care — it’s simply the billing language Medicare and commercial insurers use.

When to Bill 90837

Use 90837 when face-to-face psychotherapy lasts 53 minutes or longer and shorter time would not have met the clinical need.

Situations include:

• Elevated state of distress or emotional dysregulation
• Trauma or grief work requiring deep processing
• Severe or comorbid clinical presentations
• Time-intensive interventions (such as EMDR, CPT or ERP)
• Cognitive or communication deficits requiring repetition or clarification
• Intensive work on emotional regulation or behavioral change
• Crisis stabilization or risk management such as safety planning

90837 Documentation Requirements

• Client Information: Include patient name, date of service, and clinician signature on each page.
• Time: Record the exact start and stop times and total psychotherapy time (53+ minutes). The recorded time should reflect only the face-to-face psychotherapy time and must exclude administrative tasks such as scheduling, billing or note-writing.
• Medical Necessity: State why a 45-minute session would not have been sufficient.
• Diagnosis: The ICD-10 diagnosis should be clearly connected to the clinical need for extended psychotherapy time. The note must explicitly explain why the client required a 90837 session on that date (e.g., complexity of symptoms, intensity of interventions delivered, or clinical factors requiring prolonged therapeutic engagement).
• Treatment Plan: Show how the sessions advanced goals or stabilized risk.
• Functional Impairment: Briefly describe how the client’s symptoms are impacting daily functioning (e.g., work, home, school) in a way that supports the clinical need for extended psychotherapy time.

Common pitfalls to avoid

• Billing 90837 by default for every session
• Vague or non-clinical notes such as “supportive therapy”
• Documenting logistics instead of clinical reasons such as “client arrived early”
• Failing to link the session to treatment goals

Bottom line

45-60 minutes long sessions remain standard and clinically appropriate. Medicare defines 90837 as 53 minutes or more, and payers follow this rule. Insurers are auditing this code more often. You do not need to change your care — but you do need to document clearly so your reimbursement is secure.