Group therapy is an essential service for many behavioral health practices across Washington, providing crucial support to patients while also maximizing clinician efficiency. But when it comes to billing for these sessions, even experienced providers can run into complications. Missteps with session structure, CPT codes, and modifiers can lead to denials or worse—audits. That’s why understanding the rules around group therapy billing is critical for compliance and financial health.

As a group therapy billing specialist in Washington, Instapay Healthcare Services helps providers navigate these complex billing requirements to avoid costly errors and ensure timely reimbursements.

What Counts as Group Therapy?

In Washington, group therapy is typically billed using CPT code 90853, which refers to group psychotherapy (other than of a multiple-family group). This code applies to sessions that involve multiple patients interacting together under the supervision of a licensed clinician.

To qualify for reimbursement, group therapy must:

• Have a clear therapeutic purpose (e.g., DBT, CBT groups).
• Be facilitated by an eligible provider (e.g., LMHC, LICSW, psychologist).
• Maintain proper documentation for each participant, including start/end time and individualized notes.

If your documentation doesn’t clearly answer these questions, the payer may assume the worst: that the claim is vague, excessive, or non-reimbursable.

The Confusion Around Concurrent Sessions

One of the most misunderstood areas in behavioral health billing in Washington is concurrent group sessions. Providers sometimes attempt to run multiple groups at once or bill overlapping time slots. This is a compliance risk.

According to payer guidelines and state policies:

• A clinician cannot be physically or virtually present in more than one billable group session at the same time.
• Overlapping groups must be staffed by separate qualified providers.
• Time must be accounted for and exclusive to one group per billing entry.

Failing to follow this can trigger audits and clawbacks. If you’re unsure how to handle concurrent scheduling, consult a group therapy billing specialist in Washington to review your workflow.

Modifier Misuse: A Costly Mistake

Modifiers are essential when documenting unique billing scenarios, but improper usage is a red flag. In group therapy, one common modifier is modifier 59—used to indicate that a service is distinct or separate from others performed on the same day.

However, modifier 59 should not be used simply to bypass edits or duplicate claim denials. Misuse can raise fraud concerns.

Here’s what you can do:

Use modifier GT or 95 for telehealth group therapy, if applicable and supported by the payer.

Follow Medicaid and private payer guidelines closely—some may require modifier HQ (group setting).

As Washington’s behavioral health billing provider, Instapay ensures that modifier use aligns with payer policies and state regulations, preventing costly denials or recoupment demands.

Common Group Therapy Billing Missteps

Some of the most frequent billing errors include:

• Using individual therapy codes (e.g., 90834) for group sessions.
• Copy-pasting progress notes across all group members.
• Failing to note each patient’s specific participation and progress.
• Billing group therapy without documentation of medical necessity.

Each of these mistakes can result in payment delays, denials, or compliance investigations.

Final Thoughts

Group therapy is a valuable clinical offering, but only when billed correctly. If your practice is growing or offering more group-based services, it’s time to partner with a group therapy billing specialist in Washington who understands the nuances of payer policies and documentation standards.

At Instapay Healthcare Services, we specialize in behavioral health billing in Washington and serve as Washington’s behavioral health billing provider of choice for practices seeking accuracy, efficiency, and peace of mind. Contact us today to ensure your group therapy billing practices are audit-proof and revenue-ready.