The Ultimate Guide to 8-Minute Rule Therapy
Understanding how therapy services are billed is essential for healthcare professionals, especially those working with Medicare and outpatient services. One of the most important — and often confusing — billing standards is the 8-Minute Rule. Used primarily by Medicare, this rule determines how many billable units a therapist can charge based on the length of time they spend providing direct, one-on-one services.
In this comprehensive guide, you’ll learn:
- What the 8-Minute Rule is
- How to use it with CPT codes
- Examples of billing scenarios
- Key differences with similar rules
- Tips for accurate documentation and compliance
📘 What Is the 8-Minute Rule?
The 8-Minute Rule is a billing guideline used by Medicare Part B and some private insurers. It applies to time-based CPT codes, where billing is based on the duration of one-on-one therapy services.
According to the rule:
You must provide at least 8 minutes of a single, time-based service to bill 1 unit for that service.
If multiple services are performed, the total time spent delivering one-on-one services is calculated, and the appropriate number of billable units is determined.
⏱️ Timed vs. Untimed CPT Codes
Understanding whether a CPT (Current Procedural Terminology) code is timed or untimed is critical for applying the 8-Minute Rule correctly.
🟩 Timed Codes
These are based on the time a therapist spends delivering one-on-one services. You can bill multiple units depending on how much time is spent.
Examples include:
- 97110 – Therapeutic Exercise
- 97112 – Neuromuscular Re-education
- 97116 – Gait Training
- 97530 – Therapeutic Activities
- 97140 – Manual Therapy
🟥 Untimed Codes
These codes are billed as one unit per session, regardless of how long the service takes.
Examples include:
- 97010 – Hot/Cold Packs
- 97014 – Electrical Stimulation (unattended)
- 97161–97163 – Physical Therapy Evaluation
- 97165–97167 – Occupational Therapy Evaluation
⚠️ You do not apply the 8-Minute Rule to untimed codes.
🧮 How to Calculate Billable Units
Use this chart to determine how many units you can bill based on total time spent on timed services:
| Total Time (min) | Billable Units |
|---|---|
| 8–22 mins | 1 unit |
| 23–37 mins | 2 units |
| 38–52 mins | 3 units |
| 53–67 mins | 4 units |
| 68–82 mins | 5 units |
| 83–97 mins | 6 units |
🔄 Example Scenario
Let’s say a physical therapist provided the following services in a session:
- 18 minutes of Therapeutic Exercise (97110)
- 10 minutes of Manual Therapy (97140)
Total Timed Minutes = 28 minutes
➡️ According to the chart, 28 minutes equals 2 units.
Billing Options:
- 1 unit of 97110 + 1 unit of 97140
- OR 2 units of 97110 (since it had more time)
You cannot bill both unless each service was performed for at least 8 minutes individually. In this case, both qualify.
🧠 Key Billing Rules
- ✅ Minimum of 8 minutes must be spent on a single timed code to bill it.
- ✅ Combine all timed services to determine total billable units.
- ✅ Always round down, never up.
- ✅ Document each service with start and end times.
- ✅ Bill untimed codes separately and only once per visit.
⚖️ 8-Minute Rule vs. Rule of Eights
These two rules are often confused.
| 8-Minute Rule (Medicare) | Rule of Eights (Private Payers) |
|---|---|
| Based on total time | Based on time per CPT code |
| Allows combination of services | Each code must meet 8-minute mark |
| Used by Medicare Part B | Used by some commercial payers |
📌 Always check with individual insurance providers to confirm which rule applies.
🏥 Who Must Follow the 8-Minute Rule?
Applies To:
- Medicare Part B Outpatient Therapy
- Some Medicaid programs
- Some private insurance companies
- Outpatient rehab and private practice clinics
Does NOT Apply To:
- Medicare Part A (e.g., inpatient, SNF, hospital settings)
- Workers’ Compensation (in many states)
- Certain commercial plans (may use Rule of Eights)
📝 Tips for Accurate Documentation
Proper documentation supports compliance and avoids billing errors.
✅ Best Practices:
- Use start and stop times for each service
- Specify each CPT code used
- Describe what was done and why
- Note any rest or setup time (not billable)
🧾 Why It Matters
Getting the 8-Minute Rule right helps your clinic:
- ✅ Get paid correctly
- ✅ Avoid denials or audits
- ✅ Ensure Medicare compliance
- ✅ Boost revenue with accurate billing
- ✅ Protect patient trust and reduce legal risk
✅ Summary
| Key Point | Explanation |
|---|---|
| Rule Threshold | 8 minutes minimum for 1 unit billing |
| Applies To | Medicare Part B and some private/Medicaid payers |
| Timed Codes | Billable in multiple units if time allows |
| Untimed Codes | Only one unit per session regardless of time |
| Time Calculation | Total up all timed codes to determine units using the 8-minute rule chart |
| Documentation | Include service time, activity, and CPT code per session |
🔚 Final Thoughts
The 8-Minute Rule might seem tricky at first, but once you understand the logic and rules behind it, it becomes a powerful tool to ensure accurate and fair reimbursement for therapy services.
Whether you’re a therapist, biller, or clinic manager, mastering this rule means better billing, fewer rejections, and improved financial health for your practice.
Jane Smith – Medical Billing Specialist
With over 38 years of experience, Jane Smith helps healthcare providers manage billing, recover payments, and reduce claim denials. She specializes in insurance claims, provider credentialing, and revenue management, ensuring smooth financial operations so doctors can focus on patient care.
