One of the most common billing mistakes in outpatient physical therapy is misusing group and individual therapy codes. It seems like a small detail, but it has big consequences—denied claims, compliance issues, underpayment, or audits.
At PT Billing, we work with PT clinics across the country, and this is one of the most misunderstood parts of CPT coding. The difference isn’t just about how the session looks—it’s about how it’s documented, how it’s coded, and how it gets paid.
Let’s break it down the right way.
What Is Individual Therapy?
Individual therapy refers to a physical therapist or assistant providing one-on-one care to a single patient. It requires constant, direct interaction. It’s hands-on, skilled therapy—and that’s what payers expect when you bill certain codes.
Most one-on-one therapy codes are time-based. That means you bill in 15-minute increments, and the therapist must be directly working with the patient during that time.
Examples of these services include therapeutic exercise, manual therapy, gait training, neuromuscular re-education, and therapeutic activities. If your therapist steps away from the patient to assist someone else or take a phone call, that time is not billable under individual therapy codes.
Bottom line: if you’re billing individual codes, the session must reflect one-on-one skilled care, and your documentation needs to prove it.
What Is Group Therapy?
Group therapy, in the billing world, means that the therapist is treating multiple patients at the same time. They don’t have to be doing the same activity, but they are being supervised simultaneously.
You bill group therapy using CPT code 97150. This code is not time-based, which means you get paid a flat rate no matter how long the session lasts. The therapist must still be involved and provide skilled oversight, but they are not required to give direct one-on-one attention.
A key misconception is that group therapy is less skilled or less valid. That’s not true. It can be an appropriate billing choice—if it reflects what actually happened in the clinic.
Here’s the kicker: if your clinic is supervising two or more patients at once, even for just part of the session, and you’re billing individual codes, you’re out of compliance. That could trigger an audit or a clawback.
Why This Difference Affects Your Bottom Line
Using the wrong code doesn’t just create compliance issues—it affects your reimbursement. Group therapy generally pays less than individual therapy. So if you’re truly providing one-on-one care and billing it as group, you’re leaving money on the table.
But billing one-on-one therapy when it wasn’t actually delivered opens you up to recoupments and payer audits. Many clinics fall into this trap by accident, especially during busy times or when therapists are splitting their attention between multiple patients.
At PT Billing, we review documentation, flag inconsistencies, and help you make sure your billing reflects the reality of care delivered.
Can You Bill Both Group and Individual on the Same Day?
Yes, but only if your documentation clearly separates the services. For example, if a patient participates in a group-based therapeutic exercise session, and then receives 15 minutes of one-on-one manual therapy, you can bill both—as long as the services didn’t overlap and the documentation supports both codes.
What you can’t do is bill one-on-one therapy codes for time when the therapist was managing multiple patients, even if the care was skilled.
We see this mistake often. It’s usually unintentional, but it’s still risky. If it’s not documented right, it’s not billable.
What Payers Look For
Payers expect consistency between what was billed and what was documented. When reviewing claims, they’re asking:
- Was this service delivered as described?
- Was the therapist truly one-on-one the whole time?
- Were there multiple patients being supervised?
- Does the documentation support the complexity and time?
If there’s any doubt, they’ll deny or request a refund. Medicare in particular is strict about the difference between group and individual care. So are most commercial insurers.
This is why clean documentation matters just as much as correct coding. One supports the other.
The Most Common Mistakes Clinics Make
Here’s where clinics usually get tripped up:
- Billing individual therapy codes when supervising more than one patient
- Documenting only general exercise plans, not skilled interventions
- Failing to track exact time spent with each patient
- Assuming group therapy means less skilled care (it doesn’t)
- Using group therapy codes to bill for convenience, not accuracy
Mistakes like this are easy to make—but they’re also easy to fix once your team knows what to watch for.
How PT Billing Helps You Get It Right
At PT Billing, we specialize in helping outpatient clinics bill correctly and get paid faster—without taking compliance risks. We handle:
- Clean claims submission
- Accurate CPT code selection
- Documentation audits
- Denial prevention and appeals
- Staff training on billing best practices
We don’t just push claims through. We help you understand why your codes matter and how to protect your practice from unnecessary loss.
Final Thoughts
The difference between group and individual therapy in billing isn’t just about what happens in the clinic—it’s about how it’s documented, how it’s coded, and how it’s reimbursed.
If your team isn’t 100% clear on the rules, you’re either leaving money on the table or putting your revenue at risk.
At PT Billing, we help you avoid both.
Let’s Clean Up Your Billing—The Right Way
If you’re unsure whether your group vs. individual therapy billing is compliant, we’ll take a look. We’ve helped clinics across the country fix costly mistakes, improve revenue, and simplify documentation.
Schedule your consultation with PT Billing today. We’ll help you bill smarter, stay compliant, and get paid for the care you provide.