If you work in mental health, you have likely seen the code 90791 on your billing sheets. But do you really know what it covers? Many people mix it up with other codes. Others lose money because they do not use it correctly.
This guide will change that. We will look at the 90791 CPT code description in plain English. You will learn when to use it, when to avoid it, and how to document it properly. Let us get started.
What Is the 90791 CPT Code?
The 90791 CPT code stands for “Psychiatric diagnostic evaluation.” This is an initial assessment. It happens when a patient meets a professional for the first time to talk about their mental health.
The key point? There is no medical service attached to this code. That means no medication management. No physical exam. No prescription writing. This is purely a conversation to understand what is going on in the patient’s mind.
Who Can Use Code 90791?
Many professionals can bill for this service. Here is a quick list:
- Licensed clinical social workers (LCSW)
- Licensed professional counselors (LPC)
- Clinical psychologists (PhD or PsyD)
- Marriage and family therapists (LMFT)
- Psychiatrists (only when no medical service is done)
- Nurse practitioners (only in non-medical evaluations)
If you provide therapy or counseling, you likely qualify. The real question is not about your license. It is about what you do during the session.
The Complete 90791 CPT Code Description
Let us break this down piece by piece. The official description from the American Medical Association (AMA) says:
“Psychiatric diagnostic evaluation includes a psychiatric history, mental status examination, and the development of an initial treatment plan.”
That sounds simple. But in practice, it includes many small but important tasks.
What the 90791 Session Includes
A proper 90791 session covers these five areas:
- Psychiatric history – You ask about past mental health issues. Past hospital stays. Past therapy. Past medications. Family history of mental illness. Trauma history.
- Current symptoms – You explore what brings the patient in today. How long have the symptoms been there? How severe are they? Do they come and go?
- Mental status exam (MSE) – You observe the patient. Their appearance. Their mood. Their speech. Their thought process. Their memory. Their insight.
- Risk assessment – You ask about self-harm. Harm to others. Suicidal thoughts. Access to weapons. Past attempts.
- Initial treatment plan – You write down a plan. This could include therapy goals. A referral to a psychiatrist. A recommendation for a higher level of care.
How Long Does a 90791 Session Take?
The CPT code does not have a required time length. But in practice, most sessions last between 45 and 90 minutes.
Here is a helpful breakdown:
| Session Length | Typical Use Case |
|---|---|
| 30–45 minutes | Follow-up or focused re-assessment (not appropriate for initial 90791) |
| 45–60 minutes | Simple cases. One main issue. Good support system. |
| 60–75 minutes | Moderate complexity. Multiple issues. Some risk factors. |
| 75–90 minutes | High complexity. Trauma history. Complex family dynamics. Significant risk. |
Important note: Do not rush this session. A short 90791 may get denied by insurance. They expect a thorough evaluation.
When to Use Code 90791 (And When Not To)
This is where many professionals make mistakes. Using the wrong code leads to denied claims. It also leads to audits.
✅ Correct Uses of 90791
- A new patient comes to your private practice. You have never seen them before. You spend 60 minutes learning about their depression symptoms.
- A patient transfers from another therapist. You still need to do your own full evaluation. You cannot just accept the old therapist’s notes.
- A patient returns after two years away. Their life has changed completely. You need a new baseline.
❌ Incorrect Uses of 90791
- You already saw this patient last month for an initial evaluation. Now they are back. You cannot bill 90791 again. Use a therapy code like 90834 or 90837.
- You prescribed medication during the same session. That makes it a medical evaluation. You need to use 90792 instead (psychiatric diagnostic evaluation with medical services).
- You only spent 20 minutes on the phone with the patient. That is not an evaluation. That is a brief check-in. Use a telephone code like 98966 or none at all.
90791 vs. Other Common Codes
Many people confuse 90791 with other codes. Let us clear that up right now.
90791 vs. 90792
This is the most common confusion. Here is the difference:
| Code | Includes Medical Service? | Who Uses It? | Typical Setting |
|---|---|---|---|
| 90791 | No | Therapists, counselors, social workers | Outpatient therapy |
| 90792 | Yes (medication management, prescription, physical exam) | Psychiatrists, psychiatric nurse practitioners | Psychiatric clinics |
Example: A psychiatrist talks to a patient for 60 minutes. They only do talk therapy. They do not prescribe or adjust medication. Can they use 90791? No. Their license implies medical services are available. They must use 90792.
Another example: A social worker does a 70-minute evaluation. They never touch medication. They refer the patient to a psychiatrist later. That is a perfect 90791.
90791 vs. 90837
| Code | What It Is | When to Use |
|---|---|---|
| 90791 | Initial evaluation | First or second session |
| 90837 | Psychotherapy, 60 minutes | Follow-up sessions after the evaluation |
Important rule: You cannot bill 90791 and 90837 on the same day for the same patient. The evaluation comes first. Therapy comes later.
90791 vs. 96130
Some professionals confuse evaluation codes with testing codes. Here is the difference:
- 90791 – Conversation-based. No standardized tests. No scoring.
- 96130 – Psychological testing. You use official tools like the MMPI or Beck Depression Inventory. You score them. You interpret the results.
If you do formal testing, you can bill both 90791 and 96130 on the same day. But you must document both services separately.
Documentation Requirements for 90791
Insurance companies love to audit this code. Why? Because it pays well. And they want to make sure you earned it.
Your documentation must prove that you did a complete evaluation. Here is what to include in every 90791 note.
The 10 Essential Elements
- Reason for referral – Who sent the patient? Why now? What is the main problem?
- History of present illness – A narrative. When did symptoms start? How have they changed?
- Past psychiatric history – Previous diagnoses. Previous treatments. Previous hospitalizations. Medications tried in the past.
- Substance use history – Alcohol. Cannabis. Stimulants. Opioids. Nicotine. Caffeine. Include past and present use.
- Family history – Mental illness in parents, siblings, children. Suicide in the family. Substance use in the family.
- Social history – Living situation. Relationship status. Work or school. Legal issues. Support system.
- Medical history – Chronic illnesses. Past surgeries. Current medications (including non-psychiatric).
- Mental status exam (MSE) – At least 8–10 observations. Appearance. Attitude. Behavior. Speech. Mood. Affect. Thought process. Thought content. Cognition. Insight. Judgment.
- Risk assessment – Suicidal ideation. Self-harm. Homicidal ideation. Access to weapons. Protective factors.
- Initial treatment plan – Specific goals. Proposed frequency of sessions. Referrals made. Recommended level of care.
Sample Documentation Snippet
Here is how a good 90791 note might look:
“Patient is a 34-year-old female referred by her primary care physician due to worsening anxiety over the past 6 months. She reports panic attacks 2–3 times per week. No prior psychiatric hospitalizations. No current suicidal ideation. Mental status exam reveals anxious mood, congruent affect, goal-directed thought process, and fair insight. Initial treatment plan includes weekly CBT sessions focusing on panic management. Referral made to psychiatry for medication evaluation.”
Common Documentation Mistakes
Avoid these errors. They cause denials.
- Missing MSE – You cannot forget the mental status exam. It is a core part of the code description.
- Vague treatment plan – “Continue therapy” is not a plan. Write specific goals.
- No risk assessment – Even if the patient has no risk, document that. Write: “Denies suicidal ideation, homicidal ideation, and self-harm behavior.”
- Copy-paste errors – Do not copy from another patient’s note. Auditors catch this easily.
Reimbursement and Billing Tips
Money matters. Let us talk about what you can expect for 90791.
Average Reimbursement Rates
These numbers vary by state and insurance company. But here are rough estimates:
| Payer Type | Average Reimbursement |
|---|---|
| Medicare | 120–150 |
| Medicaid | 80–110 |
| Private insurance (e.g., United, Cigna, Aetna) | 150–220 |
| Self-pay (cash) | 175–300 (your own rate) |
Important note: Medicare does not cover 90791 for most licensed counselors and social workers. Only psychiatrists and clinical psychologists can bill Medicare for this code. Always check your local coverage determination.
How Insurance Companies Review 90791 Claims
Insurers look for three things:
- Medical necessity – Does the patient truly need a full evaluation? A simple adjustment issue may not qualify. A major depressive episode likely does.
- Completeness – Did you cover all required elements? Missing pieces lead to denial.
- No double-billing – Did you also bill for therapy on the same day? That is usually not allowed.
Tips to Reduce Denials
- Verify benefits before the session. Call the insurance company. Ask: “Does this plan cover initial psychiatric diagnostic evaluation code 90791?”
- Get authorization if needed. Some plans require pre-authorization for the first few sessions.
- Use the correct place of service code. 11 for office. 02 for telehealth (in many cases).
- Submit clean claims. Double-check the patient’s ID number. Double-check the date of service.
Telehealth and Code 90791
Can you do a 90791 evaluation over video? Yes. In most cases, insurance companies allow it.
Telehealth Rules by Payer
| Payer | Video 90791 Allowed? | Audio-Only Allowed? |
|---|---|---|
| Medicare (for eligible providers) | Yes, through 2024 (extended often) | No |
| Medicaid | Varies by state | Rarely |
| Private insurance | Mostly yes | Sometimes, with modifier |
Documentation for Telehealth 90791
Add a note in your record. Write something like:
“This 60-minute session was conducted via real-time, HIPAA-compliant video conferencing. Patient was located in their home. Provider was located in private office. Verbal consent for telehealth obtained.”
What About Phone-Only Evaluations?
This is trickier. Most payers do not reimburse 90791 for audio-only sessions. Why? Because you cannot do a proper mental status exam. You cannot see the patient’s appearance, psychomotor activity, or eye contact.
If you must do a phone evaluation, consider a different code. Or document why video was not possible. But be prepared for denials.
Frequently Asked Questions (FAQ)
Can I bill 90791 for a child or adolescent?
Yes. The code has no age limit. But you should include parent or guardian input. Document who was present. Note what information came from the child versus the parent.
How many times can I bill 90791 for the same patient?
Usually once per provider per lifetime. Some exceptions exist:
- After a gap in care of two or more years
- After a major change in functioning (e.g., brain injury, psychosis)
- When transferring from a different type of provider (e.g., from a counselor to a psychiatrist)
Does 90791 require face-to-face time?
Yes. 100% of the time must be face-to-face (or video equivalent). You cannot bill for chart review alone. You cannot bill for speaking to family members without the patient present.
Can I bill 90791 if I also do a family session on the same day?
Usually not. Choose one code. If the primary purpose is the patient’s evaluation, use 90791. If the primary purpose is family therapy without the patient present, use 90846.
What happens if I run out of time during the 90791 session?
Schedule a second session. But do not bill 90791 again. Bill a therapy code for the follow-up. Or bill 90791 for the first session and 90832 (30-minute therapy) for the second session to finish the evaluation.
Does 90791 have a time limit?
No minimum or maximum is stated. But realistically, a 30-minute session is rarely enough for a complete initial evaluation. Most insurers expect 45–60 minutes minimum.
Real-World Examples of 90791 Usage
Let us walk through three scenarios. This will help you see the code in action.
Example 1: Private Practice Therapist
Scenario: Sarah is a licensed professional counselor (LPC). A new patient, John, schedules an appointment. He reports feeling sad for months. He has never been to therapy before.
What Sarah does:
- Spends 55 minutes with John
- Takes a full history
- Completes an MSE
- Finds no suicidal thoughts
- Creates a plan: 12 weeks of CBT for depression
Code billed: 90791
Reimbursement: $180 (private insurance)
Result: Paid in full.
Example 2: Psychiatrist Without Medication
Scenario: Dr. Patel is a psychiatrist. A new patient comes in for an evaluation. They want only talk therapy. No medication. No physical exam. Dr. Patel agrees.
What Dr. Patel does:
- Spends 65 minutes with the patient
- Does a full psychiatric history and MSE
- Does not prescribe anything
- Does not review medical records
Code billed: 90792 (not 90791)
Why? Because Dr. Patel is a physician. The AMA says any psychiatric evaluation by a physician is 90792 if medical services are available, even if not used. Many psychiatrists lose money by using 90791 incorrectly.
Reimbursement: $210
Example 3: Community Mental Health
Scenario: Maria is a clinical social worker at a community clinic. A new patient comes in with complex trauma, substance use, and homelessness.
What Maria does:
- Spends 90 minutes across two appointments (one for history, one for MSE and planning)
- Completes a risk assessment (patient has passive suicidal thoughts)
- Refers to a psychiatrist and a substance use program
Code billed: 90791 for the first appointment. No code for the second appointment (or 90837 for therapy if they continued).
Result: Paid. But some insurers ask why the evaluation took two days. Maria documents clearly: “Due to patient’s distress and difficulty concentrating, evaluation was completed over two sessions. First session focused on history. Second session focused on MSE and treatment planning.”
How to Avoid Audits for Code 90791
Audits happen. But you can reduce your risk.
Red Flags That Trigger Audits
- Billing 90791 for the same patient more than once in a year
- Billing 90791 and 90837 on the same day
- Very short sessions (under 30 minutes) billed as 90791
- Missing MSE in the note
- Using templates that look identical for all patients
How to Prepare for an Audit
Keep these documents for every 90791 claim:
- The signed informed consent form
- Your full evaluation note (not just a summary)
- The treatment plan
- Any referral letters or records from other providers
If audited, send these within 15 days. Most audits close without issue if your documentation is complete.
Common Myths About 90791
Let us debunk some myths. These false beliefs cost professionals money.
Myth 1: “You can only bill 90791 if you have a doctorate.”
Truth: LPCs, LCSWs, LMFTs, and other master’s level clinicians can bill 90791. Your license level does not matter. What matters is your scope of practice and payer contracts.
Myth 2: “90791 is just an intake form.”
Truth: An intake form is paperwork. 90791 is a clinical service. You need face-to-face time. You need to apply your clinical judgment. A form alone is not enough.
Myth 3: “Medicare covers 90791 for everyone.”
Truth: Medicare only covers 90791 for psychiatrists, clinical psychologists, and some nurse practitioners. Most counselors and social workers cannot bill Medicare for this code.
Myth 4: “You can bill 90791 every year as an annual check-up.”
Truth: Insurance sees 90791 as a one-time code per provider. You cannot bill it yearly like a physical exam. Use 90834 or 90837 for ongoing therapy.
The Future of Code 90791
CPT codes change over time. Here is what to watch for.
Possible Changes in the Next 3–5 Years
- Telehealth permanence – Video evaluations may become permanently covered.
- More modifiers – Insurers may add modifiers for complexity or time.
- Integration with primary care – New codes may appear for behavioral health integration (like 99492, 99493, 99494).
For now, 90791 remains stable. Use it confidently. But stay informed. Join your state counseling or social work association. They send updates when codes change.
Additional Resources
For more help with 90791 and mental health billing, check out these trusted sources:
- American Medical Association (AMA) CPT® Professional Edition – The official code book. Buy the latest version.
- Centers for Medicare & Medicaid Services (CMS) – Search for “Medicare Physician Fee Schedule Look-Up Tool.” Enter 90791 to see your local rate.
- Your professional organization – NASW, APA, ACA, AAMFT all have billing guides for members.
[Link to free 90791 documentation template download] (Placeholder for your actual resource)
Conclusion
The 90791 CPT code is your primary tool for initial mental health evaluations. Use it when you complete a full psychiatric history, mental status exam, and treatment plan without any medical service. Document every required element. Avoid double-billing with therapy codes. And always verify insurance coverage before the session. When used correctly, 90791 ensures you are paid fairly for the important diagnostic work you do.
FAQ (Summary)
Q: What is the 90791 CPT code description?
A: It is a psychiatric diagnostic evaluation that includes history, mental status exam, and initial treatment plan, with no medical service attached.
Q: Who can bill 90791?
A: Licensed clinical social workers, professional counselors, psychologists, marriage and family therapists, and sometimes psychiatrists (if no medical service is performed).
Q: How long is a 90791 session?
A: Typically 45 to 90 minutes. No official time requirement, but shorter sessions risk denial.
Q: Can I bill 90791 for telehealth?
A: Yes, for real-time video sessions. Audio-only is rarely covered.
Q: How many times can I use 90791 for one patient?
A: Usually once per provider per lifetime, unless there is a long gap or major change in the patient’s condition.
Disclaimer: This article is for educational purposes only. Billing rules vary by location, insurance plan, and provider type. Always verify current guidelines with your payer and a certified medical coder or billing specialist before submitting claims.
