This tool helps you calculate how many billing units you can claim for time-based therapy services according to the Medicare 8-minute rule. Enter the time spent on each service separately to determine your correct billing units.
According to Medicare and most private insurers, you must track time per service. Each unit equals 15 minutes of direct contact, but you must spend at least 8 minutes to bill one unit.
Total Units: 0
Important: You must track time per service. You cannot combine minutes from different services to reach the 8-minute threshold. Each service must independently meet the minimum time requirement.
If you're a personal trainer or physical therapist billing for services, you’ve probably heard the term 8-minute rule. But what does it actually mean? And why does it matter so much when you're trying to get paid correctly for your work?
The 8-minute rule isn’t a suggestion. It’s a strict guideline used by Medicare and many private insurers in the U.S. to determine how many units of time-based therapy services you can bill for in a single session. Get it wrong, and you risk underpayment-or worse, an audit. Get it right, and you ensure fair compensation for every minute you spend with your client.
Here’s the plain truth: if you spend 22 minutes on a therapeutic activity with a client, you can’t just bill for two units. You need to know exactly how the 8-minute rule applies. And if you’re a personal trainer working with clients recovering from injury, or a physical therapist handling insurance claims, this rule directly impacts your income.
The 8-minute rule is based on time units called “units” in CPT (Current Procedural Terminology) coding. Each unit equals 15 minutes of direct, one-on-one patient contact. But here’s the twist-you don’t bill one unit for every 15 minutes. You bill based on how much time you spent over the 8-minute threshold.
Let’s break it down:
So if you spent 21 minutes on therapeutic exercise, you bill for one unit. Even though you’re 4 minutes short of 25, you still get credit because you passed the 8-minute minimum. But if you only did 7 minutes? No unit. No payment.
This isn’t about rounding up. It’s about meeting a minimum threshold. You can’t add up small chunks of time from different services to make one unit. Each service must stand on its own.
Why 8 minutes? Because it’s half of 15. Medicare’s system was designed to prevent overbilling while still giving providers credit for meaningful time spent. If you spend less than half a unit (8 minutes), it’s considered too minimal to bill. If you hit 8 minutes or more, it’s considered substantial enough to count as a full unit.
This rule applies only to time-based codes-not procedure-based ones. For example:
For non-time-based codes, you bill one unit per service, no matter how long it took. But for the time-based ones? You need to track minutes like a stopwatch.
Imagine a client comes in for a 45-minute session. Here’s what you did:
Now, apply the 8-minute rule to each:
Total = 4 units. You billed 4 units, and you’re paid for 4 units. Simple.
But what if you did 14 minutes of exercise and 13 minutes of manual therapy? That’s 27 minutes total-but you can’t combine them. You have to treat them separately. So:
Still only 2 units. Even though you spent 27 minutes total, you didn’t hit the 23-minute threshold for a second unit in either service.
People mess this up all the time. Here are the top three errors:
One trainer I know billed for 3 units after a 40-minute session because he thought 40 divided by 15 was 2.66, so he rounded up. He got audited. Medicare said he billed for 3 units but only had 2 full units (23-37 minutes). He had to pay back the overpayment.
Medicare started the 8-minute rule, but most private insurers follow it too. Blue Cross, Aetna, UnitedHealthcare-they all use the same system. Some may have slight variations, but 95% of them stick to this standard.
Don’t assume your insurance payer is different. Always check their provider manual. But if you’re billing Medicare-compliant codes, you’re already following the rule most insurers expect.
And if you’re a personal trainer working with clients who have insurance coverage for rehab? You’re still bound by this rule. Even if you’re not a licensed physical therapist, if you’re submitting claims under CPT codes, the 8-minute rule applies.
Manual timers don’t cut it. You need to track time per service, not just total session time.
Use a simple system:
Many clinics use electronic health record (EHR) systems that auto-calculate units based on time input. If you’re using one, make sure it’s set up correctly. If you’re using paper notes, create a checklist:
Don’t rely on memory. Don’t guess. If you’re not tracking time per service, you’re gambling with your revenue.
Underbilling means you’re leaving money on the table. Overbilling? That’s fraud.
Medicare audits happen. They look at your documentation, your time logs, and your billing patterns. If you’re consistently billing 3 units for 35-minute sessions, but your notes say you only spent 12 minutes on each service? That’s a red flag.
Penalties can include:
It’s not worth the risk. Even one mistake can cost you thousands.
The 8-minute rule isn’t complicated. It’s just precise. And in billing, precision pays.
Many personal trainers work with clients recovering from surgery or injury. If you’re using CPT codes like 97110 or 97140 to bill insurance, you’re subject to the same rules as a PT.
But if you’re working with clients who pay out-of-pocket? Then the 8-minute rule doesn’t apply. You can charge by the hour, by the session, or by any structure you want.
The rule only matters when you’re submitting claims to insurance. So if you’re not billing Medicare or private insurers, you can ignore it. But if you’re even thinking about billing, learn it now.
Only if you’re billing insurance using CPT codes. If you’re a personal trainer working with clients who pay out-of-pocket, the rule doesn’t apply. But if you’re submitting claims for services like therapeutic exercise or manual therapy under Medicare or private insurance, you must follow the 8-minute rule-regardless of your license. Insurance companies don’t care if you’re a PT or a trainer; they care about the code you use.
No. Each CPT code must be tracked separately. You can’t add 7 minutes of gait training and 8 minutes of therapeutic exercise to make a single unit. Each service must independently meet the 8-minute minimum to be billed. This is a common mistake that leads to audits.
You can bill one unit. The rule is not “more than 8 minutes”-it’s “8 minutes or more.” So 8 minutes, 8 minutes and 1 second, or 22 minutes-all count as one unit. But 7 minutes and 59 seconds? That’s not billable.
Almost all major insurers in the U.S. follow Medicare’s 8-minute rule for time-based CPT codes. This includes Blue Cross, Aetna, UnitedHealthcare, and Humana. Some smaller or specialty plans may vary, but it’s rare. If you’re billing Medicare-compliant codes, you’re already aligned with what most payers expect.
Yes. Many EHR systems used by physical therapists and clinics have built-in unit calculators. There are also free apps like TherapyNotes, SimplePractice, and WebPT that let you input time per service and auto-calculate units. Even a simple spreadsheet with formulas can work-just make sure you’re tracking time per code, not total session time.
The 8-minute rule is simple, but it’s not obvious. It’s not about how long your session is-it’s about how you break it down. If you’re billing insurance, this rule controls your pay. Get it right, and you’re paid fairly. Get it wrong, and you’re either underpaid or at risk of penalties.
Track your time per service. Know your codes. Don’t guess. And never assume you can combine minutes from different services. This isn’t just paperwork-it’s how you get paid for the work you do.
