Time is a very important factor for coding physical therapy codes. Medicare has a special 8 minute rule for billing the physical therapy procedures. Today, we will actually learn how rehab therapists use the Medicare 8 Minute Rule to determine what to bill Medicare for therapy services provided for a particular date of service.

Medicare’s 8 Minute Rule for time-based codes is invented for proper billing of physical therapy codes. 

What are timed Physical therapy CPT codes?

We all know about CPT codes, but what are timed CPT codes? Some, CPT codes are c based on the time used for the exam, for example in moderate sedation we have separate code for initial 15 minutes of service and we have to use another CPT code for additional 15 minutes. The same way we have bill physical therapy codes based on time. Below are few physical therapy codes used by medical coders.

97001 Physical Therapy Evaluation

97002 Physical Therapy Re-Evaluation

97110 Therapeutic exercises

97140 Manual Therapy (ie. STM, JM)

97530 Therapeutic Activities: Use of dynamic activities to improve functional performance

97535 Self-care/home management training (ie. ADL’s, safety procedures, instructions)

97112 Neuromuscular Re-education

97113 Aquatic therapy

97116 Gait training

97124 Massage

97014 Electrical stimulation

97012 Traction, mechanical

97010 Hot or cold packs

97033 Iontophoresis

97035 Ultrasound

97034 Contrast bath

97036 Hubbard tank

97139 Unlisted procedure

97039 Unlisted modality

There are few codes based on time or Timed CPT codes. Below are few of them.

• 97032 – Electrical Stimulation (Manual)
• 97033 – Iontophoresis
• 97035 – Ultrasound
• 97039 – Unlisted
• 97110 – Therapeutic Exercise
• 97112 – Neuromuscular Reeducation
• 97116 – Gait Training
• 97124 – Massage
• 97139 – Unlisted
• 97140- Manual Therapy
• 97530 – Therapeutic Activity

The 8 minute rule revolves around these procedure codes. So, let us go forward to learn about this rule. Basically 8 minutes equal to 1 unit and multiple of 8 minute should then be calculated and converted into units. Below is example to calculate 8 minute as units.

UnitsNumber of Minutes

0 Units< 8 Minutes

1 Unit>= 8 Minutes and <= 22 minutes

2 Units>= 23 Minutes and <= 37 minutes

3 Units>= 38 Minutes and <= 52 minutes

4 Units>= 53 Minutes and <= 67 minutes

5 Units>= 68 Minutes and <= 82 minutes

6 Units>= 83 Minutes and <= 97 minutes

7 Units>= 98 Minutes and <= 112 minutes

8 Units>= 113 Minutes and <= 127 minutes

Their are also list of untimed CPT code for billing purpose. Below are the list of untimed CPT codes.

• 97010- Hot/Cold Pack
• 97012- Mechanical traction
• 97016- Vasopneumatic devices
• 92506- Evaluation of speech, language, voice, communication, and/or auditory processing disorder; individual
• 92522- Evaluation of speech sound production

So, we have to remember only about either timed or untimed codes for Physical Therapy billing purposes.

• Untimed codes are reported as one unit per day.
• Timed codes are reported using the 8 Minute Rule.

New PT and OT Evaluation and Re-Evaluation Codes

The new CPT codes for evaluation and re-evaluation codes not based on time or untimed procedure codes. These new codes included Physical Therapy (PT) and Occupation Therapy (OT) codes as well. Below is a list of new CPT codes.

• 97161- PT evaluation- low complexity
• 97162- PT evaluation- moderate complexity
• 97163- PT evaluation- high complexity
• 97164- PT re-evaluation
• 97165- OT evaluation- low complexity
• 97166- OT evaluation- moderate complexity
• 97167- OT evaluation- high complexity
• 97168- OT re-evaluation

Difference between AMA and Medicare 8 minute rule

As per AMA guidelines, the code should not be billed additional units based on the cumulative total of your remainders. You cannot bill for any of those remainders unless one of them totals at least eight minutes, if there are leftover minutes. So, in the example above, you could not bill for any additional units, because neither the 3 minutes of manual therapy nor the 5 minutes of therapeutic exercise meets the 8-minute minimum.