Billing and coding
How to use CPT code 90785 for interactive complexity
CPT code 90785 is an add-on code used to reflect communication difficulties during a psychiatric procedure, such as a psychotherapy session.
December 21, 2023 • Updated on October 27, 2025
11 min read
As essential as CPT codes are for billing, they can also be confusing. One common source of confusion is CPT code 90785, which reflects “interactive complexity” in a session. Read on to learn more about CPT code 90785, and how you should (and shouldn’t) be using it when filing claims for therapy sessions.
CPT code 90785 description
CPT code 90785 is an add-on code used to reflect communication difficulties during a psychiatric procedure, such as a psychotherapy session. It’s always used in conjunction with another CPT code, and never alone. For example, you may add a 90785 code when you’re billing for psychotherapy if communication barriers were present that required additional clinical effort — making the interaction more complex, not longer, due to those challenges.
According to Nadine Thomas, Headway’s provider operations lead, a psychotherapist with any license type can bill this code. “But it only applies to psychotherapy, not family/couples or crisis psychotherapy,” she says. In addition, psychiatrists and nurse practitioners can only use the interactive complexity code when they’re actually conducting psychotherapy.
Code 90785 is only applicable as an add-on to the following CPT codes:
- 90791 (initial assessment)
- 90792 (initial assessment, with medical services)
- 90832 (psychotherapy, 30 minutes)
- 90834 (psychotherapy, 45 minutes)
- 90837 (psychotherapy, 60 minutes)
- 90833 (psychotherapy add-on code, 30 minutes)
- 90836 (psychotherapy add-on code, 45 minutes)
- 90838 (psychotherapy add-on code, 60 minutes)
- 90853 (group therapy)
Practice in-network with confidence
Simplify insurance and save time on your entire workflow — from compliance and billing to credentialing and admin.
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.
What is “interactive complexity”?
Interactive complexity refers to specific communication challenges that complicate treatment and require you to adjust your clinical approach.
When 90785 does apply
Your documentation must show both what the barrier was and how it impacted the session.
Examples include:
- A parent or guardian interferes with communication (e.g., answering questions for the patient).
- A patient requires alternate methods, such as visual aids for expressive aphasia or an assistive device for nonverbal communication.
- Severe behavioral disruption prevents treatment (e.g., patient sobbing uncontrollably or child throwing objects).
- A mandated report for suspected abuse or neglect is discussed during the session.
How to document interactive complexity
Your documentation for this code should explain which element(s) of interactive complexity were present. The elements can be one or more of the following:
- Maladaptive communication among multiple participants in session (client plus additional persons)
- Caregiver emotions or behavior that interferes with implementation of treatment plan
- Evidence or disclosure of a sentinel event and a mandated report to a third party
- Use of of play equipment, physical devices, or translator to overcome significant communication barrier
A compliant note must include:
- The communication barrier (e.g., “guardian answered all questions for the patient”).
- The impact on the session (e.g., “required redirection and interfered with therapeutic progress”).
Notes that only state “90785 used due to communication barriers” are insufficient.
"It’s important that your documentation clearly details the circumstances that caused any communication barriers or sentinel events, as well as the agency to which these were reported,” says Headway's senior medical coding specialist Jessica Belvin, CPC, CPMA
If documentation does not clearly describe the interactive complexity factors present during the session, the claim may not meet payer requirements and is at risk of being denied or subject to repayment.
Here are some examples of how you might document interactive complexity in your notes, by each present element:
Maladaptive communication:
Patient’s mother was included for a portion of the intake session. The mother was highly agitated and disagreed with the level of treatment services and proposed objectives of the treatment plan.
Caregiver emotions:
During this initial assessment for this school-aged child there were reports by the divorced parents, reporting declining grades, temper outbursts, and bedtime difficulties. Parents were extremely anxious and repeatedly asked questions about the treatment process. Each parent continually challenges the other’s observations of the patient.
Sentinel event:
During the course of the current visit, the daughter of the patient discloses that her father has recently been the victim of elder abuse by a neighbor. The therapist’s obligations under state statutes to report this as elder abuse are explained to the patient, and the report process is initiated.
Use of devices:
During the session, the patient used assistive communication devices due to ALS-related expressive language difficulties, which significantly impacted the therapeutic interaction and required additional time for both explanation and interpretation of non-verbal cues.
When NOT to use 90785
It can be confusing to determine whether you should or shouldn’t use code 90785. Keep in mind a few key scenarios in which interactive complexity isn’t the right code:
- According to Thomas, seeing a client through telehealth — while it may indeed add a layer of complexity to your session — isn’t enough justification to bill code 90785, a qualifying barrier must be present.
- Additionally, it’s not required (or even valid) when the patient brings another person to therapy, but the communication doesn’t present any extra complexity.
- Interpreter use alone (this is a violation of the ADA)
- A patient who is tearful but able to engage
- Play therapy as a standalone approach
The 90785 code cannot be used along with the following codes:
- Psychotherapy for crisis codes (90839, 90840)
- Family psychotherapy codes (90846, 90847, 90849)
- E/M (evaluation and management) service where no psychotherapy service is reported
The American Academy of Child and Adolescent Psychiatry also offers helpful guidance on when reporting interactive complexity isn’t appropriate:
- Multiple participants in the visit with straightforward communication
- Client attends visit individually with no sentinel event or language barriers
- Treatment plan explained during the visit and understood without significant interference by caretaker emotions or behaviors
Practice in-network with confidence
Simplify insurance and save time on your entire workflow — from compliance and billing to credentialing and admin.
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.
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.
© 2025 Therapymatch, Inc. dba Headway. All rights reserved. No part of this publication may be reproduced without permission.
Billing and coding
The 10+ most common CPT codes (and how to use them)
Understand the ins and outs of CPT codes to help make documentation and billing more efficient — and give you more time to focus on other areas of your practice.
How to bill insurance for therapy
Headway strives to simplify billing insurance so you can focus on providing care. Read our comprehensive guide to mental health billing.
The 13 most common psychiatry CPT codes (and how to use them)
Understand the ins and outs of CPT codes to help make documentation and billing more efficient — and give you more time to focus on other areas of your practice.