The arithmetic behind the invoice
How physical therapy is actually billed
Physical therapy is billed in fifteen-minute units of hands-on time, counted by a rule most patients have never heard of. Knowing it is the difference between reading your bill and merely receiving it.
How a visit turns into units on a bill. Physical therapy is billed in fifteen-minute units of hands-on time, and Medicare's eight-minute rule decides how many: add the timed minutes, divide by fifteen, and add one more unit if eight or more minutes are left over. That rule is why the difference between a busy hour and a padded one is visible on the bill if you know where to look. Ask us for the codes on any visit and you will get them, along with what was actually done in each unit.
There are two kinds of billing code in physical therapy. Untimed codes are billed once per visit regardless of how long they took — the evaluation is the obvious one. Timed codes are billed in units of fifteen minutes of direct, one-to-one time, and those are where the arithmetic lives.
Medicare's eight-minute rule decides how many units a visit produces. Add up the timed minutes, divide by fifteen, and add one more unit if eight or more minutes remain. Forty-five minutes of hands-on time is three units. Fifty-three minutes is four. Fifty-two is three. CMS made no change to this for 2026 and it is set out in chapter 5 of the Claims Processing Manual.
Why the rule tells you something about the clinic
The critical words are “direct, one-to-one”. Minutes in which a clinician is not with you do not count. Time on a heat pack, time on a machine that runs itself, time spent doing your exercises while the therapist works with somebody in the next room — none of that is one-to-one time and none of it belongs in a timed unit.
Which means a clinic running three patients an hour on staggered starts has an arithmetic problem. There are only sixty minutes of a clinician in an hour, and they cannot honestly appear in three different patients' timed units at once. The eight-minute rule is one of the very few places where how a practice is actually run becomes visible on a piece of paper.
Our appointments are sixty minutes with one clinician who is in the room. That is a commercial decision with a cost, and it is also what makes the units on our bills straightforwardly true.
What the codes usually are
The evaluation is untimed and comes in three complexity levels — low, moderate and high — chosen by the complexity of your presentation rather than by how long it took. Re-evaluations are a separate untimed code and we do not charge you for the visit-four reassessment.
The common timed codes are therapeutic exercise, therapeutic activities, neuromuscular re-education, manual therapy and gait training. Each is fifteen minutes of one-to-one time. A typical hour with us produces three or four units across two or three of those codes, depending on what your problem needed that day.
Group therapy has its own code and it is not billed as one-to-one time. If you were ever treated in a group of four and billed as though you had been treated alone, that is the specific thing the distinction exists to prevent.
Ask for your codes. You will get them.
Any visit, any time, without a reason: the codes billed, the units, and what was actually done in each one. Not a summary — the line items. If a clinic is reluctant to give you that, the reluctance is the answer.
We are not claiming this makes us unusually virtuous. It makes us legible, which is a lower bar and one the profession clears less often than it should. A bill you cannot check is a bill you are being asked to take on trust, and there is no reason for that to be the arrangement.
In order
How this works in practice
The evaluation is billed once
Untimed, at one of three complexity levels set by your presentation rather than by the clock.
Treatment time is counted in one-to-one minutes
Minutes a clinician is actually with you. Not machine time, not time spent waiting.
Total the timed minutes, divide by fifteen
That is your base number of units.
Add one more unit for eight or more leftover minutes
The eight-minute rule. Fifty-three minutes is four units; fifty-two is three.
Reassessment is not billed here
We are not going to charge you to check whether our own plan is working.
Ask for the line items whenever you want them
Codes, units and what was done in each. No reason needed.
Questions we are actually asked
How physical therapy is actually billed — frequently asked
What is the 8-minute rule?
Medicare's method for turning treatment time into billable units. Add the direct one-to-one minutes, divide by fifteen, and add one more unit if eight or more minutes are left over. It is set out in chapter 5 of the Medicare Claims Processing Manual and CMS made no change to it for 2026. Most commercial insurers follow the same approach, though some use a substantially similar rule of their own.
Why does my bill show four units for a one-hour visit?
Because roughly fifty-three or more of those sixty minutes were direct one-to-one treatment. Three units is forty-five to fifty-two minutes, four is fifty-three to sixty-seven. Ask us for the line items on any visit and you will get the codes, the units and what was done in each.
Does time on a machine count towards my units?
Not towards timed one-to-one units, no. Modalities that run without a clinician present are billed under their own codes, some of which are untimed. This is a large part of why a plan built around passive machines looks the way it does on an invoice.
Can I be billed for an hour if the therapist was with someone else?
Not for one-to-one timed units, which by definition require the clinician to be with you. If you were treated alongside others, group therapy has its own code. This is the single most useful thing to understand about how physical therapy billing can go wrong.
Will you tell me what a visit will cost before I book?
Yes. If you are paying yourself, $190 for the initial evaluation and $140 per treatment visit, published on the pricing page. If you are using insurance we verify your benefit before the first visit and tell you your copay or coinsurance, and what your plan's visit cap is.
Read next
Related reading
Sixty minutes, one to one, with the therapist you chose
Book an appointment
The booking page shows each therapist's own diary rather than a generic grid, so a slot you can see is a slot that is genuinely free. Most people do not need a doctor's referral to start — New York's direct access law runs to ten visits or thirty days — though Workers' Compensation, No-Fault and Medicare each need one from the first visit. If you are not sure which of those you are, telephone and we will work it out before you book.