Ever spend an hour helping a patient move better, and get paid for only part of it? You’re not alone. For physical therapists, therapy billing can often feel like decoding a secret language: modifiers, units, time thresholds, and insurance quirks. It’s complex, sometimes frustrating, and always important. Whether you run a solo practice or manage a busy therapy clinic, getting physical therapy billing right is not just about compliance – it’s about protecting your revenue and your time.
Let’s simplify therapy billing – no jargon, no fluff, just what you really need to know.
Why Therapy Billing is So Confusing in the First Place
When people search online for therapy billing, they often stumble into mental health or psychotherapy articles. That’s because the term “therapy” also includes psychotherapy, which dominates the conversation. But in your world – the world of physical therapy (PT) – therapy billing means something very different. Add to this the fact that billing for PT involves time-based services, Medicare-specific rules, and therapy modifiers, and you’ve got a recipe for confusion. So let’s cut through that noise.
The Core of Therapy Billing: Time, Units, and Codes
At the heart of therapy billing lies a simple question: How do you bill accurately for the time you spend with patients?
Most therapy services are billed using CPT codes (Current Procedural Terminology). Some codes are time-based, like therapeutic exercise (CPT 97110), which is billed in 15-minute increments, while others are service-based, billed once per session regardless of time. But here’s the catch: you can’t just count minutes and divide by 15.
The “8-Minute Rule” – A Rule That Isn’t as Simple as It Sounds
Let’s say you spent 53 minutes doing a combination of manual therapy and neuromuscular re-education. That doesn’t automatically mean 3 units.
According to Medicare’s 8-minute rule:
- A unit of time must be at least 8 minutes
- You total the time spent on timed procedures, then divide accordingly
Here’s a breakdown:
- 8–22 minutes = 1 unit
- 23–37 minutes = 2 units
- 38–52 minutes = 3 units
- 53–67 minutes = 4 units
Sounds fair. But it’s easy to miscalculate when juggling multiple modalities, evals, or untimed procedures. That’s where many therapists lose money, simply by underreporting or rounding incorrectly. Understanding how to accurately calculate time units is central to billing for physical therapy services.
Medicare vs. Commercial Insurance: Know the Difference
Physical therapy Medicare billing requires exact documentation, timely use of modifiers, and awareness of annual caps. Medicare billing comes with its own rulebook, and it’s strict:
- Follow the 8-minute rule to the letter
- Apply the correct modifiers (GP, KX, etc.)
- Track annual therapy thresholds and use appropriate documentation to exceed them
Private insurance plans may not use the 8-minute rule. Some follow CMS guidelines, others have their own unit calculation models, and some reimburse at flat session rates. So, always confirm the billing policy per payer and yes, this often means dealing with inconsistent logic across your claims.
How to Bill Therapy Units (Without Losing Your Mind)
Let’s say your treatment session looks like this:
- 20 minutes of therapeutic exercise (97110)
- 15 minutes of manual therapy (97140)
- 10 minutes of ultrasound (97035)
That’s a total of 45 timed minutes, which equates to 3 units under the 8-minute rule. But now, you need to decide which codes get billed and how many units each. Here’s where billing precision matters:
- 97110 = 1 unit (20 minutes)
- 97140 = 1 unit (15 minutes)
- 97035 = 1 unit (10 minutes)
Always prioritize the code with the highest allowed reimbursement when choosing which services to assign multiple units.
Top 3 Mistakes Physical Therapists Make in Therapy Billing
- Under-coding or over-coding units: Many PTs bill 2 units for a 30-minute session without checking the proper breakdown. That’s either money left on the table or a red flag for an audit.
- Missing required modifiers: Especially with Medicare, missing the GP modifier (services delivered under a therapy plan of care) can trigger rejections or denials.
- Using untimed codes incorrectly: For example, billing an untimed modality like hot/cold packs (CPT 97010) in units when it’s only billable once per visit.
Is Therapy Fully Covered by Insurance? Not Always.
Most patients assume therapy is fully covered, but the truth is:
- Coverage varies widely based on plan type
- Many plans require pre-authorizations, co-pays, or documentation of medical necessity
- Visit caps and therapy thresholds (especially with Medicare) may limit what’s reimbursed
This is why accurate billing, proper documentation, and timely appeals are essential parts of the billing process, not afterthoughts.
Outsourcing Billing Services for Therapists: Is It Worth It?
While in-house billing gives you control, it also adds stress and administrative load. Outsourcing therapy billing to a specialist who knows PT billing codes, payer nuances, and unit calculations can improve cash flow and reduce denials, especially for smaller practices. Outsourcing medical billing for physical therapy to a specialist who understands payer rules, unit calculations, and denial trends can improve your bottom line.
If you’ve ever said, “I just want to focus on patients and not billing headaches,” then yes – it might be time to outsource.
Billing Shouldn’t Undermine Your Care
You entered this profession to help people move, recover, and thrive, not to spend hours decoding modifiers or chasing denied claims. Physical therapy billing isn’t easy, but with the right knowledge and systems in place, it can be manageable, accurate, and even predictable. Whether you manage billing yourself or delegate it, the goal is the same: get paid fairly for the care you provide.
Need Help with Therapy Billing?
At Medisys, we specialize in physical therapy billing that’s accurate, compliant, and payer-specific. Our goal is simple: help you maximize revenue while you focus on your patients. Visit www.medisysdata.com to learn more or contact us if you need tailored billing support for your therapy clinic.
Disclaimer:
The CPT® (Current Procedural Terminology) codes are copyrighted by the American Medical Association (AMA).
*The descriptions and usage guidelines for these codes are subject to change. The coding example provided reflects the guidelines as of the date of publication and is intended for informational purposes only. Healthcare providers and billers should always verify current coding standards and payer-specific requirements before submitting claims.
