Mental Health Billing Workflow Overview
Mental health billing requires a workflow that accommodates the ongoing nature of treatment, the session-based service model, and the authorization requirements that most payers impose on mental health services. Unlike acute care billing where each visit is independent, mental health billing involves tracking patient progress through treatment episodes that span weeks or months, with authorization milestones that must be met to maintain coverage.
Step 1: Intake and Benefits Verification
The billing process begins at patient intake, before the first clinical session. Verify the patient mental health benefits specifically, not just their general medical coverage. Key items to confirm: Is outpatient mental health covered? What is the copay or coinsurance for mental health visits? Does the plan require prior authorization? Is there an annual session limit? Are telehealth mental health sessions covered at parity?
Mental health parity laws require most group health plans to cover mental health at the same level as medical/surgical benefits. However, parity applies to cost-sharing and treatment limits, not necessarily to authorization requirements. A plan can cover unlimited medical visits without authorization while requiring authorization for mental health after the 8th session, as long as the authorization process is comparable to what they apply to similar medical services.
Step 2: Initial Assessment and Treatment Planning
The first session is typically a diagnostic evaluation (90791 or 90792) that establishes the diagnosis and creates the initial treatment plan. The treatment plan should include specific, measurable goals tied to the diagnosis, recommended session frequency, expected treatment duration, and the type of therapy to be used. This treatment plan becomes the foundation for all subsequent authorization requests.
Billing the initial evaluation correctly is important. Code 90791 (without medical services) is used by non-prescribing providers. Code 90792 (with medical services) is used by psychiatrists or psychiatric nurse practitioners who also perform a medical evaluation. Using the wrong code results in either denial or underpayment.
Step 3: Ongoing Session Documentation and Coding
Each session requires a progress note that documents the time spent in psychotherapy, clinical interventions used, patient response, and progress toward treatment plan goals. The note must support the CPT code billed. Time documentation is the most frequent audit target in mental health billing.
Code selection follows the session duration: 90832 for 16-37 minutes, 90834 for 38-52 minutes, 90837 for 53+ minutes. When the session includes both psychotherapy and medication management (psychiatry), use the E/M code (99213-99215) with the appropriate psychotherapy add-on code (90833, 90836, 90838).
Step 4: Claim Submission and Tracking
Submit claims within 48 hours of the session. Include the correct place of service (11 for office, 10 for telehealth at patient home, 02 for telehealth other), the rendering provider NPI, the appropriate diagnosis code from the treatment plan, and any required modifiers (95 for telehealth). Track claim status through the clearinghouse and follow up on any rejections within 24 hours.
Step 5: Authorization Renewal and Treatment Review
As the initial authorization period approaches its limit, prepare a re-authorization request. This requires an updated treatment plan showing progress made, revised goals, and clinical justification for continued treatment. Include standardized assessment scores (PHQ-9, GAD-7) that demonstrate ongoing clinical need. Submit the re-authorization request at least 2 weeks before the current authorization expires to prevent coverage gaps.
Step 6: Patient Billing and Collections
Collect copays at the time of each session. For patients with deductibles, provide cost estimates at intake and collect estimated patient responsibility before or at the first visit. Issue patient statements within 7 days of insurance payment posting. Follow up on unpaid balances at 30 and 60 days. Balances over 90 days in mental health have extremely low collection rates and should be evaluated for write-off or payment plan arrangements.