Mental Health Billing Errors: What Patients Should Know

Mental health services are among the fastest-growing segments of healthcare spending, and billing errors in this area are both common and uniquely harmful. Unlike a broken bone or a blood test, mental health treatment involves sensitive personal information, ongoing therapeutic relationships, and billing structures that many patients do not understand. When billing errors occur, patients often pay without questioning because they want to avoid disrupting their care.

The average cost of a therapy session in the United States ranges from $100 to $250 for in-network providers and $150 to $400+ for out-of-network providers. Over a year of weekly therapy, that is $5,200 to $20,000+. Even small per-session billing errors compound quickly at that frequency.

This guide covers the seven most common mental health billing errors, your rights under federal parity law, and how to dispute errors without jeopardizing your care.

How mental health billing works

Mental health billing uses a specific set of CPT codes that differ from regular office visit codes. The two main categories are:

• Psychotherapy codes (90832, 90834, 90837) -- Time-based codes for talk therapy, billed based on the actual face-to-face time with the patient.
• Psychiatric diagnostic evaluation (90791, 90792) -- Used for the initial assessment. 90791 is without medical services; 90792 includes medical evaluation (used by psychiatrists who also do medication management).

Additionally, many psychiatrists and psychiatric nurse practitioners bill E/M codes (99211-99215) for medication management visits, sometimes combined with psychotherapy add-on codes.

The billing provider's credential (psychiatrist, psychologist, LCSW, LPC, LMFT) affects both the billing rate and whether the service is covered by insurance. This is a frequent source of errors.

Psychotherapy time-based codes

Psychotherapy CPT codes are strictly time-based. The code determines a time range, and the actual session time must fall within that range. Using the wrong code is one of the most common mental health billing errors.

The three psychotherapy codes:

• 90832 -- Psychotherapy, 16-37 minutes. Medicare rate: approximately $60-$75.
• 90834 -- Psychotherapy, 38-52 minutes. Medicare rate: approximately $95-$115. This is the standard "therapy hour" code.
• 90837 -- Psychotherapy, 53+ minutes. Medicare rate: approximately $130-$155.

Common time-code errors:

• Upcoding from 90834 to 90837. This is the most common psychotherapy billing error. A standard 45-50 minute session should be billed as 90834 (38-52 minutes). If the bill shows 90837 (53+ minutes), the session must have lasted at least 53 minutes of actual face-to-face psychotherapy time -- not including check-in, scheduling, or paperwork. The difference between the two codes is $35-$50 per session. Over a year of weekly therapy, that is $1,800-$2,600 in overbilling.
• Billing 90834 for a 30-minute session. If your appointments are consistently 30 minutes, the correct code is 90832 (16-37 minutes), not 90834.
• Not counting time accurately. The clock starts when psychotherapy begins -- not when you check in at the front desk, not when you sit down in the waiting room. Travel time and administrative time are excluded.

Track your actual session times. Note when your therapist begins the session (not when you arrive) and when it ends. If your sessions consistently run 45-50 minutes but you are being billed with code 90837 (53+ minutes), you are likely being overcharged $35-$50 per visit.

E/M code add-on billing errors

When a psychiatrist provides both psychotherapy and medication management in the same visit, the billing involves an E/M code plus a psychotherapy add-on code. This is where billing gets complex and errors multiply.

Psychotherapy add-on codes:

• 90833 -- Psychotherapy add-on, 16-37 minutes (billed with an E/M code)
• 90836 -- Psychotherapy add-on, 38-52 minutes (billed with an E/M code)
• 90838 -- Psychotherapy add-on, 53+ minutes (billed with an E/M code)

The correct billing for a combined visit is: one E/M code (e.g., 99214) for the medication management portion, plus one add-on code (e.g., 90833) for the psychotherapy portion. The time for each component should be documented separately.

Common errors:

• Billing a standalone psychotherapy code instead of the add-on. If both medication management and therapy were provided in the same visit, the bill should show an E/M code + an add-on (e.g., 99214 + 90833). If it shows an E/M code + a standalone code (e.g., 99214 + 90834), that is incorrect. Standalone psychotherapy codes cannot be billed with E/M codes on the same date.
• Billing the add-on without an E/M code. Add-on codes (90833, 90836, 90838) cannot be billed alone -- they require a primary E/M code. If you see only an add-on code on a claim, the E/M code is missing.
• Upcoding the E/M level. A brief medication check (5-10 minutes discussing medication effects and adjusting dosage) does not justify a level 4 E/M code (99214). A level 2 or 3 code (99212 or 99213) is more appropriate for routine medication management.

Out-of-network surprise billing

Mental health is one of the most difficult healthcare specialties for finding in-network providers. The American Psychological Association reports that mental health providers participate in insurance networks at significantly lower rates than other medical specialists. This means many patients end up with out-of-network providers, sometimes without realizing it.

Common scenarios:

• Provider leaves the network mid-treatment. Your therapist was in-network when you started, but their contract with your insurer ended. You continue seeing them and suddenly receive out-of-network charges. Many states have "continuity of care" provisions that require insurers to cover ongoing treatment at in-network rates for a transition period (typically 60-90 days).
• Hospital-based mental health services. If you receive mental health treatment at an in-network hospital, the No Surprises Act protects you from balance billing by out-of-network providers at that facility. This includes inpatient psychiatric services and ER psychiatric evaluations.
• Provider directory errors. Your insurer's online directory listed a provider as in-network, but they are actually out-of-network. If you relied on the directory in good faith, you may be able to hold the insurer to in-network rates. Document the directory listing (screenshot it) before your first visit.

Parity law violations

The Mental Health Parity and Addiction Equity Act (MHPAEA) is one of the most important and most frequently violated consumer protection laws in healthcare. It requires that health plans cover mental health and substance use disorder benefits at the same level as medical/surgical benefits. When plans violate parity, patients pay more for mental health care than they would for equivalent medical care.

What parity requires:

• Equal cost-sharing. Your copay, coinsurance, and deductible for mental health visits cannot be higher than for medical visits in the same benefit classification (inpatient, outpatient, emergency). If your plan charges a $40 copay for a specialist medical visit but $60 for a therapist visit, that is a potential parity violation.
• Equal visit limits. If your plan does not limit the number of medical specialist visits per year, it cannot limit the number of therapy sessions per year.
• Equal prior authorization requirements. If your plan does not require prior authorization for medical specialist visits, it cannot require prior authorization for outpatient mental health visits.
• Equal network adequacy. The plan must make reasonable efforts to provide the same level of network access for mental health providers as for medical providers.

How to identify a parity violation:

1. Compare your mental health benefits to your medical/surgical benefits in the same benefit classification.
2. If the cost-sharing, visit limits, prior authorization requirements, or network restrictions are more restrictive for mental health, it may be a parity violation.
3. Request a copy of your plan's MHPAEA compliance analysis. Plans are required to make this available upon request under the 2024 MHPAEA final rule.

Where to file a parity complaint:

• Employer-sponsored plans (ERISA): U.S. Department of Labor, Employee Benefits Security Administration, at 1-866-444-3272.
• Individual and small group plans: Your state insurance commissioner. See our state rights page for your state's contact information.
• Medicare/Medicaid managed care: CMS.

Wrong provider credential billed

Mental health services can be provided by providers with different credentials, and each credential has different billing implications:

• Psychiatrist (MD/DO) -- Can bill both E/M codes and psychotherapy codes. Typically the highest reimbursement rate.
• Psychologist (PhD/PsyD) -- Can bill psychotherapy and evaluation codes. Cannot prescribe medications in most states.
• Licensed Clinical Social Worker (LCSW) -- Can bill psychotherapy codes. Reimbursement rate is typically 75% of the psychiatrist/psychologist rate under Medicare.
• Licensed Professional Counselor (LPC/LMHC) -- Coverage varies by state and insurer. Medicare began covering LPC/LMHC services in 2024 at 75% of the physician rate.
• Licensed Marriage and Family Therapist (LMFT) -- Similar to LPC. Medicare coverage began in 2024.

Common credential billing errors:

• Billing under a psychiatrist's NPI when a lower-level provider treated you. If you see a therapist (LCSW, LPC) in a psychiatrist's practice, the claim should be billed under the treating provider's NPI, not the supervising psychiatrist's NPI. Billing under the psychiatrist's NPI inflates the reimbursement rate -- this is called "incident-to" billing, and the rules for when it is allowed are strict.
• Wrong provider type on the claim. Check the rendering provider on your EOB. Does it show the person who actually treated you? If you saw a social worker but the claim shows a psychologist, the credential is wrong.
• Provider not credentialed with your insurer. If your provider has not completed the insurer's credentialing process, the claim may be denied or processed at out-of-network rates even though the provider intended to be in-network.

Group therapy billed as individual

Group therapy is a legitimate and effective treatment modality. It is also significantly less expensive than individual therapy -- and that creates a billing error incentive.

The codes:

• 90853 -- Group psychotherapy (other than family). Medicare rate: approximately $25-$35. This is a flat per-patient charge regardless of group size.
• 90834 -- Individual psychotherapy, 38-52 minutes. Medicare rate: approximately $95-$115.

The difference is striking: group therapy costs about one-third of individual therapy. If your session involved a therapist leading a group of patients through shared therapeutic work, the correct code is 90853, not an individual psychotherapy code.

When the line blurs:

• Couples therapy. Couples therapy involves two patients and is not group therapy. It is typically billed under 90847 (family psychotherapy with patient present) or 90834/90837 with one patient as the identified client.
• Family therapy. Family therapy is billed under 90846 (without patient present) or 90847 (with patient present). These are separate from both individual and group therapy codes.
• "Group" of two. Some practices run very small groups (2-3 patients). These are still group sessions if the therapeutic work is shared. An individual code should not be used simply because the group was small.

Telehealth billing errors

Telehealth has become a standard delivery method for mental health services. The billing is mostly the same as in-person care, but with specific modifiers and place-of-service codes that create error opportunities.

How telehealth billing should work:

• The same psychotherapy CPT codes are used (90832, 90834, 90837).
• Place of service code 10 (telehealth provided in patient's home) or 02 (telehealth provided other) should be used.
• Modifier -95 or -GT may be added to indicate the service was delivered via telehealth.

Common telehealth billing errors:

• Facility fee charged for telehealth. If you attended a telehealth session from your home, there is no facility fee. If a facility fee appears on your bill for a home-based telehealth session, that is an error.
• Wrong place of service code. Using place of service 11 (office) for a telehealth session may result in a higher reimbursement rate in some payment systems. The code should reflect where the patient is located.
• Telephone vs. video billing. Audio-only (telephone) therapy sessions use different codes (99441-99443) or specific modifiers. If your session was audio-only but billed as a video session, the code may be wrong, and the reimbursement rate may differ.
• Session time inflation. This applies to in-person sessions too, but telehealth makes it easier to verify: if your video call lasted 40 minutes but the bill shows 90837 (53+ minutes), the time does not match.

How to check your mental health bill

1. Track your session times. Note when each session starts and ends. This is the single most useful piece of information for verifying psychotherapy billing.
2. Get your EOB for each session. Your EOB shows the CPT code billed, the rendering provider, the allowed amount, and your patient responsibility.
3. Verify the CPT code matches the session length. 90832 for 16-37 minutes, 90834 for 38-52 minutes, 90837 for 53+ minutes. If the code does not match your actual session time, dispute it.
4. Check the rendering provider. Confirm that the provider listed on the claim is the person who actually treated you.
5. Compare mental health and medical cost-sharing. If your copay for therapy is higher than for a comparable medical specialist visit, request your plan's parity compliance documentation.
6. For telehealth: check for facility fees. If your sessions are conducted from home via video, no facility fee should appear.
7. Use the CPT lookup tool. Verify the code description and Medicare rate for each code on your bill with our CPT/HCPCS lookup tool.

What to do when you find an error

1. Talk to your provider first. Mental health billing errors are often administrative, not intentional. Many therapists bill their own claims without a professional billing staff. A respectful conversation may resolve the issue quickly. Frame it factually: "I noticed my last session was billed as 90837, but our session was about 45 minutes. I believe the correct code is 90834."
2. Request an itemized statement. If you have not received one, ask. It should show the CPT code, date, provider, and charge for every session.
3. Contact your insurer. For claim denials, parity violations, or out-of-network issues, your insurer's member services can guide the appeal process.
4. Send a written dispute. Our dispute letter generator can create a letter with the appropriate regulatory citations.
5. For parity violations: File a complaint with your state insurance commissioner or the U.S. Department of Labor (for employer-sponsored plans).
6. Protect your therapeutic relationship. You can dispute a bill without ending therapy. Most providers want billing to be accurate and will work with you to correct errors. If a provider responds negatively to a legitimate billing question, that itself is a red flag.

For more on the dispute process, see our universal dispute guide and our dispute letter template guide. If your insurer denied a mental health claim, our insurance billing errors guide covers the appeal process, including parity violations. For state-specific billing protections and where to file complaints, see our state rights guide.

Disclaimer: This guide is for educational purposes only and does not constitute legal, financial, medical, or mental health advice. Mental health billing rules vary by provider type, state, and insurance plan. Parity law requirements described here are based on federal MHPAEA provisions as of early 2026. State laws may provide additional protections. Consult a licensed professional for advice specific to your circumstances.