What is mental health billing?

Mental health billing is the process of submitting insurance claims for behavioral health services using CPT codes where therapy code selection is based on session time, DSM-5-aligned ICD-10 diagnosis codes, and authorization management through session-block approval structures. It differs from medical billing in code set, documentation requirements, claims routing (often to a separate MBHO), authorization mechanics, and federal parity law protections. A practice that applies medical billing logic to mental health services produces a higher denial rate and undercollects on correctly delivered services.

What CPT codes are used in mental health billing?

The primary mental health CPT codes are 90791 (diagnostic evaluation without medical services), 90792 (diagnostic evaluation with medical services), 90832/90834/90837 (individual psychotherapy at 16-37, 38-52, and 53+ minutes), 90853 (group therapy), 90847/90846 (family therapy with/without patient), and 90833/90836/90838 (psychotherapy add-ons for combined E/M and therapy sessions). Therapy code selection is determined by the documented session time, not by clinical complexity. The documented time must match the code billed on every claim.

What is a managed behavioral health organization and why does it matter?

An MBHO is a company contracted by a health plan to manage behavioral health benefits separately from medical benefits. Mental health claims for patients whose plans use an MBHO must go to the MBHO — not the medical payer — or they will be denied automatically. Providers must also be credentialed with the MBHO separately from the health plan. Identifying the MBHO at insurance verification before the first session is a required front-end step in mental health billing that prevents the most common and most avoidable category of behavioral health claim denials.

How does time-based billing work in mental health?

Psychotherapy CPT codes are selected based on the total face-to-face time of the psychotherapy component: 90832 for 16-37 minutes, 90834 for 38-52 minutes, 90837 for 53 or more minutes. The documented time must match the code billed. Habitually billing 90837 for all sessions regardless of actual session duration is a compliance exposure and creates a denial risk when payers review the uniform distribution. Session time must be explicitly documented in every clinical note and the code must reflect the actual documented time, not a default or assumption about typical session length.

What is the Mental Health Parity Act and how does it affect billing?

MHPAEA requires that health plans apply the same treatment limitations, authorization requirements, and coverage criteria to mental health benefits as they apply to comparable medical and surgical benefits. When mental health claims are denied under criteria that are more restrictive than what would apply to a comparable medical service, the denial may be a parity violation. Parity appeals have a legal basis that standard medical necessity appeals don’t — and they can be escalated to state insurance commissioners when internal appeals fail. Practices that passively write off parity-violating denials are leaving recoverable revenue on the table and failing to assert patient rights under federal law.

How does authorization work for ongoing mental health treatment?

Most commercial plans authorize ongoing therapy in session blocks — typically 6 to 12 sessions at a time. When the block is exhausted, clinical renewal documentation must be submitted and approved before additional sessions are covered. Renewal documentation must demonstrate continued medical necessity: active diagnosis with documented severity, treatment progress, goals not yet achieved, and clinical rationale for the authorized frequency. Session-count tracking against the authorized block is the process control that ensures renewal is initiated before the block runs out — preventing the delivery of unauthorized sessions that will deny regardless of clinical appropriateness.

Mental Health Billing : CPT Codes, MBHO & Parity Law