If you're running a behavioral health treatment center, IOP, PHP, or MAT program, you already know the billing landscape is more complex than it should be. One missing modifier, one vague progress note, or one mismatched credential can turn a clean claim into a denial. The difference between collecting 80% of your billable revenue and 95% usually comes down to knowing which codes to use, when to use them, and what documentation keeps you safe in an audit.
This reference guide covers the top CPT codes behavioral health addiction billing teams use every day across all levels of care. It's organized by program type, includes compliance notes for each code category, and highlights the audit triggers that catch most programs off guard. Bookmark this page. You'll need it.
Assessment and Intake Codes: Building the Foundation
Every treatment episode starts with an assessment. The codes you use here set the tone for medical necessity documentation throughout the entire episode of care. According to the CMS annual update for 2026, these codes remain the standard for intake across all behavioral health settings.
90791 is your primary psychiatric diagnostic evaluation code. It covers the initial assessment without medical services. Most commercial payers and Medicaid plans reimburse this at $150 to $250 depending on region and credential. You need a licensed clinician (LCSW, LMFT, LPC, psychologist, or physician) to bill it. The documentation must include presenting problem, history of present illness, psychiatric history, substance use history, mental status exam, diagnosis, and initial treatment plan. Auditors look for specificity here. Vague statements like "patient reports depression" won't hold up. You need onset, duration, frequency, severity, and functional impairment.
96130 and 96132 are psychological testing evaluation codes used when you need standardized assessment instruments beyond clinical interview. 96130 is the first hour, 96132 is each additional hour. These require a psychologist or other qualified healthcare professional. Use these when you're administering and interpreting tools like the Beck Depression Inventory, Minnesota Multiphasic Personality Inventory, or Addiction Severity Index as part of a formal psychological evaluation. Document the specific tests used, raw scores, interpretation, and how results inform the treatment plan.
H0001 covers alcohol and drug assessment. This is a Medicaid HCPCS code that many state plans prefer over 90791 for substance use disorder-specific intake. Reimbursement ranges from $80 to $180. Credential requirements vary by state, but most allow licensed clinicians and certified addiction counselors (CADCs, CASACs) to bill it. The key audit protection here is demonstrating that the assessment uses ASAM criteria and documents placement justification for the level of care you're recommending.
H0002 is the behavioral health screening code, typically used for brief assessments (15 to 30 minutes) to determine if a full evaluation is needed. This is common in crisis settings, emergency departments, or community screening programs. Reimbursement is lower, usually $25 to $60, but it's appropriate when you're doing triage rather than comprehensive assessment.
Outpatient Individual Therapy: The Revenue Backbone
Individual therapy codes are the most frequently billed services in outpatient behavioral health. Getting these right matters because even small errors multiply across hundreds of claims per month. The most used CPT codes addiction treatment 2026 billing teams rely on are 90832, 90834, and 90837, all with the HF modifier for substance use disorder treatment.
90832 is psychotherapy, 30 minutes with patient. The actual time must be 16 to 37 minutes. Anything less gets downcoded or denied. Reimbursement typically ranges from $60 to $100. You need a licensed clinician. The progress note must include subjective report, objective observations, interventions used, patient response, and plan for next session. The progress note structure you use determines whether this claim survives an audit.
90834 is psychotherapy, 45 minutes with patient. The time threshold is 38 to 52 minutes. This is the workhorse code for most outpatient sessions. Reimbursement runs $90 to $150. Use the same documentation standards as 90832, but auditors expect more detail in the intervention section when you're billing for more time. Describe specific therapeutic techniques, patient engagement level, and measurable progress toward treatment plan goals.
90837 is psychotherapy, 60 minutes with patient. Time threshold is 53 minutes or more. Reimbursement is $120 to $200. This code often gets audited because it's easy to bill 90837 when the actual face-to-face time was only 45 minutes. Document start and end times in your EHR. If you're doing telehealth, add modifier 95 or GT depending on payer preference. The AMA CPT 2026 code set maintains telehealth guidance in Appendix P and T.
The HF modifier indicates substance use disorder treatment. Many state Medicaid plans require it for SUD services. Some commercial payers ignore it. Know your payer rules. Billing 90834 without HF when your state Medicaid plan requires it will result in denial, even if everything else is correct.
Group Therapy Codes: Where Programs Leave Money on the Table
Group therapy is cost-effective clinically and financially, but it's also where billing gets messy. The three main codes are 90853, H0005, and S9480. Each has different rules, and using the wrong one costs you money.
90853 is group psychotherapy, CPT code. It's time-based: typically billed per session regardless of length, though some payers expect 45 to 90 minutes. Reimbursement is $25 to $50 per patient. You need a licensed clinician to facilitate. The common audit trigger here is group size. Most payers expect 3 to 12 patients. If you're running groups with 15 or 20 people, expect scrutiny. Document attendance with sign-in sheets, include group topic and therapeutic interventions in your note, and show how the group aligns with each patient's individual treatment plan.
H0005 is alcohol and drug group counseling. This is the Medicaid HCPCS code for SUD-specific group therapy. Reimbursement ranges from $20 to $45 per patient. Many state plans allow certified addiction counselors to bill this, not just licensed clinicians. That's a huge advantage for programs that employ CADCs. The billing structure for H0005 varies by state, so verify your local Medicaid rules on group size limits and time requirements.
S9480 is an unlisted behavioral health service code that some payers use for intensive outpatient group sessions. It's less standardized, so reimbursement varies widely. Some payers bundle multiple S9480 units into a daily IOP rate. Others pay per unit. The key compliance point: never bill 90853 and S9480 for the same session. That's double billing.
Across all group codes, the documentation standard is the same: attendance roster, group topic, therapeutic modality used, patient participation level, and progress toward individual treatment goals. Generic notes like "group discussed relapse prevention" fail audits. You need specifics: which patients participated, what interventions you used, and how the group addressed individual treatment plan objectives.
IOP and PHP Billing: The Daily Claim Structure That Protects Revenue
Intensive outpatient programs and partial hospitalization programs generate significant revenue, but they also have the highest denial rates when billing isn't structured correctly. The core codes are H0015 for IOP and S9480 for PHP, though some states use different codes.
H0015 is alcohol and drug intensive outpatient treatment. It's typically billed as a daily rate covering 9 to 19 hours per week across at least 3 days. Reimbursement ranges from $100 to $250 per day depending on state Medicaid plan and whether you're using the base code or adding modifiers for specific service components. The compliance requirement here is time documentation. You must show that the patient attended the required hours each week. Most IOP programs leave 15 to 20% of billable revenue uncollected because they don't track attendance accurately or they fail to bill for patients who attended partial weeks.
The clean daily claim structure for IOP includes: date of service, H0015 code, appropriate modifiers (HF for SUD, sometimes UA for group or UK for individual components), total hours attended that day, and supporting documentation showing which groups and individual sessions the patient completed. If your state Medicaid plan uses a bundled daily rate, you cannot separately bill 90834 or 90853 on the same day. That's bundling, and it triggers audits.
S9480 is used by some payers for PHP. Partial hospitalization is typically 20+ hours per week, more intensive than IOP but less than residential. Reimbursement is higher, often $200 to $400 per day. The medical necessity documentation must show why outpatient therapy and IOP are insufficient. Auditors look for recent psychiatric decompensation, safety risk, or functional impairment severe enough to require this level of care. If your documentation says "patient requested PHP," that's not medical necessity. You need clinical justification.
For both IOP and PHP, the individual counseling component within the program often requires separate documentation even when bundled into the daily rate. Track it anyway. If you ever need to appeal a denial or respond to an audit, you'll need proof that the patient received the individual therapy sessions your program promises.
MAT and OTP Codes: The Complete Medication-Assisted Treatment Billing Picture
Medication-assisted treatment billing varies dramatically depending on whether you're running an opioid treatment program (OTP) with daily observed dosing or an office-based MAT program with monthly prescribing visits. The codes are completely different.
H0020 is alcohol and drug medication administration and/or substance abuse treatment services. This covers the actual administration of medications like methadone or buprenorphine in an OTP setting. It's typically billed per day or per dose. Reimbursement ranges from $15 to $40 per administration. You need nursing or medical staff credentials to bill it. The documentation must include medication name, dose, route, time administered, patient response, and any side effects or concerns.
G2067 through G2080 are the bundled OTP codes effective in 2026. These codes cover the full weekly bundle of services in an opioid treatment program: medication, dispensing, counseling, and care coordination. G2067 is the base weekly bundle, and subsequent codes (G2068, G2069, etc.) cover additional services and take-home doses. Reimbursement varies by bundle level, typically $150 to $400 per week. The compliance requirement is that you must provide all the bundled services you're billing for. If you bill G2067 but the patient didn't receive counseling that week, that's fraud. Track every service component.
99213 and 99214 with HF modifier are used for office-based MAT visits. These are evaluation and management codes for established patients. 99213 is a straightforward visit, typically 20 to 29 minutes, reimbursed at $90 to $130. 99214 is moderate complexity, typically 30 to 39 minutes, reimbursed at $130 to $180. Use these when a physician or nurse practitioner is seeing the patient for medication management, monitoring response to buprenorphine or naltrexone, and adjusting treatment. The documentation must include history, exam, medical decision-making, and prescription details. The HF modifier signals this is SUD treatment, which matters for some payers' utilization management and reporting.
The audit risk in MAT billing is under-documentation of medical necessity for ongoing medication. Initial prescribing is easy to justify. But when you're billing 99213 every month for two years, auditors want to see ongoing assessment of treatment response, documented reasons for dose adjustments, and evidence that the patient still meets criteria for MAT. Generic notes fail here. You need specifics on cravings, substance use, functional improvement, and side effect management.
Residential and Detox Codes: Level of Care Definitions and Documentation Requirements
Residential treatment and detoxification services use HCPCS H-codes that define specific levels of care. These codes have strict medical necessity thresholds, and the documentation requirements are higher than outpatient services because the reimbursement is significantly higher.
H0008 is alcohol and drug detoxification, per diem. This covers medically monitored or medically managed withdrawal services, typically in a residential setting with 24-hour nursing and physician oversight. Reimbursement ranges from $300 to $800 per day depending on whether it's Level 3.2-WM (clinically managed residential withdrawal) or Level 4-WM (medically managed intensive inpatient withdrawal). The documentation must include CIWA or COWS scores, vital signs, medication administration records, physician orders, and daily progress notes showing withdrawal severity and response to treatment. The medical necessity threshold requires documented physiological dependence and withdrawal symptoms severe enough to require 24-hour monitoring.
H0009, H0010, H0011, H0012, H0013, H0014 cover various residential treatment levels. H0009 is typically short-term residential (Level 3.1), H0010 is long-term residential (Level 3.5), and the others cover specific subacute or transitional levels. Reimbursement ranges from $150 to $400 per day. Medicaid rates are usually at the lower end; commercial payers sometimes negotiate higher rates. The compliance requirement across all these codes is demonstrating that the patient meets ASAM criteria for residential level of care. That means documented failure at lower levels of care, severity of addiction, co-occurring disorders, living environment risk, or safety concerns that make outpatient treatment insufficient.
H0017 and H0018 cover behavioral health residential treatment for children and adolescents. H0017 is per diem, H0018 is per month. These are used for youth residential programs treating SUD and co-occurring mental health disorders. The documentation requirements include not just clinical necessity but also educational services coordination, family involvement, and discharge planning to a lower level of care. Auditors scrutinize these codes because residential treatment for minors is expensive and sometimes used inappropriately when intensive outpatient or home-based services would be sufficient.
H0019 is behavioral health residential treatment for adults, per diem. This overlaps with some of the other residential codes, and payer preference varies. Some state Medicaid plans use H0019 as the default residential code; others use the H0009-H0014 series. Know your payer's fee schedule. The documentation standard is the same: ASAM criteria justification, daily progress notes, treatment plan updates at least every 30 days, and discharge planning that shows step-down to outpatient or IOP when the patient is clinically stable.
Across all residential and detox codes, the most common audit trigger is length of stay not matching clinical documentation. If your average detox stay is 7 days but your progress notes show the patient was medically stable on day 3, auditors will question days 4 through 7. Document continued medical necessity every day. If the patient is still there, there must be a clinical reason documented in the chart.
HCPCS Codes Behavioral Health Complete List: Beyond the Core Codes
The codes covered above represent the most frequently used services, but behavioral health billing includes dozens of additional HCPCS codes for specialized services. The complete HCPCS behavioral health reference includes codes for crisis intervention (H0031, H2011), peer support services (H0038), case management (H0006), and family counseling (H0040).
H0040 is particularly underutilized. It covers family counseling for substance use disorder treatment, typically reimbursed at $50 to $100 per session. Most programs offer family sessions but forget to bill them, or they incorrectly bill 90847 (family psychotherapy with patient present) when H0040 is the appropriate code for SUD-focused family work. The family counseling billing structure varies by payer, but the revenue opportunity is real if you track these sessions and bill them correctly.
Crisis codes like H2011 (crisis intervention, per 15 minutes) are essential for programs that provide mobile crisis response or 24-hour crisis support. Reimbursement is typically $25 to $50 per 15-minute unit. The documentation must show the nature of the crisis, interventions provided, outcome, and safety plan. Generic crisis notes fail audits. You need specifics on what the crisis was, what you did, and why it required crisis-level intervention rather than routine clinical contact.
The guidance from SAMHSA on Certified Community Behavioral Health Clinics for 2026 emphasizes comprehensive service delivery and appropriate use of the full range of behavioral health codes. Programs participating in CCBHC demonstrations must track and bill all qualifying services, not just the high-volume therapy codes.
Compliance Notes: What Keeps You Safe in an Audit
Knowing the codes is half the battle. The other half is documentation and compliance. Every code category has specific audit triggers, and knowing them helps you build documentation practices that protect revenue.
The most common audit triggers across all behavioral health billing are: missing or vague progress notes, time documentation that doesn't match billed codes, credential mismatches (billing a code that requires a licensed clinician when the service was provided by an unlicensed counselor), lack of medical necessity documentation for higher levels of care, and bundling errors (billing separately for services that should be included in a daily or weekly rate).
The documentation that protects you includes: specific, measurable descriptions of patient presentation and progress; start and end times for time-based codes; credentials and signatures of rendering providers; treatment plans that justify the level of care and frequency of services; and regular updates showing ongoing medical necessity for continued treatment.
Credential requirements vary by state and payer. Some states allow licensed professional counselors to bill all psychotherapy codes; others restrict certain codes to physicians, psychologists, or clinical social workers. Some Medicaid plans allow certified addiction counselors to bill H-codes but not CPT codes. Know your state's scope of practice laws and your payers' credentialing requirements. Billing a code you're not credentialed for is fraud, even if the service was appropriate and well-documented.
The 2026 updates to behavioral health billing emphasize telehealth documentation, especially for audio-only services. If you're billing telehealth codes, document the modality (video or audio), the reason if audio-only was used instead of video, and confirmation that the patient consented to telehealth. These details matter in audits.
Why Most Programs Don't Collect What They've Earned
Even programs with good clinical documentation often leave 15 to 20% of billable revenue uncollected. The reasons are usually operational, not clinical. Common issues include: not tracking all billable services (especially groups, family sessions, and case management), billing the wrong code for the service provided, missing modifiers that trigger automatic denials, failing to follow up on denied claims, and under-documenting time for time-based codes.
The fix isn't hiring more billers. It's building systems that capture services at the point of delivery, match the right code to each service, ensure documentation meets payer requirements before the claim goes out, and track denials to identify patterns. That requires billing expertise specific to behavioral health, not just general medical billing knowledge.
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If your treatment center is losing revenue to billing errors, claim denials, or under-documented services, you don't have to fix it alone. ForwardCare provides MSO billing and revenue cycle management specifically for addiction and behavioral health treatment programs. We know every code, every modifier, every payer quirk, and every audit risk because this is all we do.
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If you're ready to stop leaving money on the table and start collecting what you've earned, reach out to ForwardCare. Let's talk about your program, your billing challenges, and how we can help you build a revenue cycle that actually works. Contact us today for a free billing assessment.
