CPT Code 90791: Psychiatric diagnostic evaluation

When to Use CPT 90791

Use CPT code 90791 when billing for psychiatric diagnostic evaluation. This code is used by licensed therapists (LCSW, LPC, MFT, Psychologist) for outpatient sessions.

Adding CPT 90791 to a Superbill

When generating a superbill with CPT 90791, include the ICD-10 diagnosis code, date of service, fee charged, amount paid, and your NPI number. Superbilled pre-fills common therapy CPT codes automatically.

Common ICD-10 Pairings

These diagnosis codes are frequently used alongside CPT 90791:

Documentation Requirements

Include comprehensive history, mental status exam, differential diagnoses, and initial treatment plan. Document medical necessity for evaluation.

Common Denial Reasons

• ✗ Billed more than once per patient without justification for re-evaluation
• ✗ Missing documentation of medical necessity or clinical rationale
• ✗ Insufficient detail in history or mental status exam

Got one of these on a remittance? Decode the denial code.

Reimbursement Expectations

OON reimbursement typically 50-70% of UCR. Expect $100-$280 from commercial insurers for initial evaluations.