Clinical psychologists (PhD, PsyD) are among the few non-physician mental health providers with full independent practice authority under Medicare Part B. Unlike LCSWs, LMHCs, or marriage and family therapists, clinical psychologists can diagnose and treat without physician supervision or referral requirements.
Enrollment basics
Clinical psychologists enroll via CMS-855I or PECOS. Requirements:
- Doctoral degree in psychology (PhD, PsyD, or EdD in psychology)
- Two years of supervised clinical experience (post-doctoral)
- State licensure at the independent practice level
- Authorization to diagnose and treat mental illness under state law
- Type 1 NPI (individual)
Covered services
Medicare Part B covers the following when provided by an enrolled clinical psychologist:
- Individual psychotherapy (90832, 90834, 90837)
- Group psychotherapy (90853)
- Family psychotherapy (90846, 90847)
- Psychiatric diagnostic evaluation (90791)
- Psychological and neuropsychological testing (96130-96139)
- Health and behavior assessment/intervention (96156, 96158, 96159, 96164, 96165, 96167, 96168, 96170, 96171)
- Crisis psychotherapy (90839, 90840)
What clinical psychologists cannot do under Medicare
- Prescribe medications (in most states — some states allow psychologists with additional training to prescribe)
- Bill for medical evaluation and management (E&M) services
- Admit patients to a hospital under their own admitting privileges (though they can provide inpatient psychotherapy)
Independent practice — no physician supervision required
This is the key distinction. A clinical psychologist can:
- Diagnose a new patient without a physician referral
- Establish and carry out their own treatment plan
- Bill Medicare independently without incident-to arrangement
- Practice in any setting (office, hospital, nursing facility, telehealth)
⚠️ Note: While physician supervision is not required for clinical practice, some Medicare Advantage plans require a physician referral or authorization for mental health services. Original Medicare does not — but check each MA plan’s requirements separately.
Psychological and neuropsychological testing
Testing services are among the highest-scrutiny areas in clinical psychology billing. Medicare requires:
- Medical necessity documentation
- Testing performed by or under direct supervision of the psychologist
- Interpretation by the psychologist (not delegated)
- Report in the medical record documenting the clinical question, tests administered, results, and recommendations
Key applications
- CMS-855I — individual enrollment
- CMS-855R — reassignment to group
Ask Mae if you have questions about testing documentation, the difference between health and behavior codes vs. psychotherapy codes, or group practice enrollment.