Specialty
Physical Therapy Medical Billing
The eight-minute rule, NCCI edits and a threshold that stops payment mid-year if nobody is watching.
What makes physical therapy billing different
Physical therapy billing turns on unit arithmetic. Timed codes are billed in units derived from total treatment minutes, and the boundary between one unit and two is narrow enough that sloppy time recording costs real money every single visit.
Then there are the code-pair edits. Several of the most common PT combinations are bundled by NCCI unless a distinct-service modifier is justified, and the justification has to exist in the documentation before the modifier is applied.
Eight-minute rule arithmetic
Units come from total timed minutes, not from what was done longest. Miscounting by a few minutes changes the unit count and the payment.
Bundled code pairs
97140 with 97530 is the classic example. It needs a distinct-service modifier and documentation of separate sites or separate time blocks.
Therapy threshold and KX
Once the annual threshold is passed, the KX modifier attests to medical necessity. Missing it stops payment for the rest of the year.
Plan of care certification
Certification is required at intervals. An expired plan of care invalidates everything billed under it, retroactively.
Ask any billing company this
“How do you calculate my units, and what is my current per-visit average?”
A company that bills your specialty properly will answer this in one sentence. A company that treats every specialty the same will answer it with a brochure.A note on accuracy. Coding rules, coverage policies and payer edits change continually, and the specifics above reflect general practice rather than any individual payer contract or local coverage determination. Treat this page as a map of where to look, not as coding advice for a particular claim.