Billing and coding
How to use CPT code 90791
Code 90791 is officially deemed a “diagnostic evaluation,” but you might know it better as an initial assessment. It typically happens in your first session with a client.
December 21, 2023
11 min read
CPT code 90791 description
Code 90791 represents your initial assessment of your client. It’s the session where you gather information about the clients symptoms in order to establish a diagnosis and formulate their treatment plan.
This is is how the American Medical Association defines 90791 in the official CPT codebook:
Psychiatric diagnostic evaluation (without medical services)
Psychiatric diagnostic evaluation is an integrated biopsychosocial assessment, including history, mental status, and recommendations.
The evaluation may include communication with family or other sources and review and ordering of diagnostic studies.
Many types of licensed mental health providers can use CPT code 90791.This code is most frequently used by:
- Licensed Clinical Social Workers (LCSW)
- Licensed Professional Counselors (LPC)
- Licensed Marriage Family Therapists (LMFT)
- Clinical Psychologists (CP)
- Licensed Psychologists (LP)
Your documentation for this code should include all the standard elements of an intake note, including:
- Session details: Including patient name and date of birth on every page, start and stop times, date, and place of service
- History of present illness
- Biopsychosocial assessment
- Mental status exam (at least 5 elements)
- Risk assessment
- Initial plan of treatment and plan for next session
- Diagnosis and functional status
- Name, credentials and signature of provider who completed assessment within 72 hours of service
Complete documentation for 90791 should include both the intake note and your bio-psycho-social assessment, as well as any diagnostic-specific assessment like the PHQ-9 for depression, GAD 7 for anxiety, or the Alcohol Use Disorders Identification Test (AUDIT-C) for substance abuse.
It’s important to use the code that most accurately reflects the time you spent with the patient to treat their condition, and ensure that documentation for the session supports the chosen code.
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CPT code 90791 time frame
The code 90791 is not associated with any specific time component, but clinicians often spend 45 minutes or more conducting a full assessment.
CPT code 90791 reimbursement rates
Reimbursement rates for sessions billed with 90791 will vary depending on the plan, your contract, your location, and your license type. The right partnership can boost reimbursement rates, too. Headway has strong relationships with many of the nation’s top insurance carriers, allowing us to negotiate competitive reimbursement rates that make accepting insurance both easy and profitable for our providers.
How often can CPT code 90791 be billed for one client?
Most payers will reimburse 90791 once every 6 months, per client.
Code 90791 cannot be reported on the same day as an evaluation and management service for the same patient, or on the same day as psychotherapy services (including for crisis).
Use code 90785 in conjunction with 90791 when the diagnostic evaluation includes interactive complexity services.
What’s the difference between 90791 and 90792?
Code 90791 is used to represent an intake assessment for care that does not include medical services.
In contrast, code 90792 is used for an intake assessment for care that does include medical services, such as ordering diagnostic work or prescribing medications. For this reason, 90792 can only be billed by a qualified licensed provider like a psychiatrist or nurse practitioner.
This document is intended for educational purposes only. It is designed to facilitate compliance with payer requirements and applicable law, but please note that the applicable laws and requirements vary from payer to payer and state to state. Please check with your legal counsel or state licensing board for specific requirements.
Add-on codes that are often used with CPT code 90791
Several billing codes may be used along with CPT code 90791. These include:
- Code 90785, which is used for appointments with “interactive complexity,” such as working with a non-verbal child or also communicating with a third party, like a family member or probation officer.
- Code 99354, which is used for extended intake sessions that last from 91-150 minutes.
- Code 99355, which is used for each additional 30 minutes that a session lasts beyond 150 minutes.
Remember that code 90791 is used for sessions that do not include medical services. If you’re looking to add on codes for medical services, you’ll likely need to use code 90792 instead.
Common mistakes when billing CPT code 90791
In addition to confusing codes 90791 and 90792, as discussed above, providers may run into difficulty if they try to use code 90791 repeatedly for the same patient. Typically, it can only be used once per patient, per year. It should not be used for follow-up visits or on the same day as psychotherapy services are delivered.
Another common mistake is failing to provide enough documentation along with code 90791. Make sure you’ve included all relevant components listed above. Headway providers can use the platform’s included intake and documentation templates to make sure nothing falls through the cracks.
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There are a lot of nuts and bolts that go into running a private therapy practice, from the complexities of billing to insurance compliance requirements. Headway is here to help with all of those tasks, streamlining and simplifying administrative responsibilities like credentialing, scheduling, documentation, and billing. Plus, our providers enjoy consistent and competitive bi-weekly pay, thanks to our partnerships with leading payers. We take care of all of your behind-the-scenes needs to make being a therapist simpler and more profitable.
This content is for general informational and educational purposes only and does not constitute clinical, legal, financial, or professional advice. All decisions should be made at the discretion of the individual or organization, in consultation with qualified clinical, legal, or other appropriate professionals.
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