Physical therapy medical billing: the fine print that quietly denies your claims

Physical therapy has some of the most particular billing in outpatient care, and most of it turns on time and paperwork rather than the treatment itself. Take the way units are counted. Medicare adds up your total timed minutes and divides them into blocks; a lot of commercial plans count each service separately instead. The same visit legitimately bills as a different number of units depending on the payer, so a practice that uses one habit for everyone gets downcoded on half its claims.

Then there is the certification. Outpatient therapy needs a signed plan of care from the physician within a set window, and re-signed as care continues. When that signature is late or missing, the claim denies on audit even though the therapy was appropriate and the patient got better. And once a patient's therapy for the year passes a set dollar amount, every claim after it has to carry an attestation that the care is still necessary, a running total no busy clinic tracks by hand.

For an independent practice with no biller, that is a lot of small requirements, each of which quietly costs money.

Altair is the done-for-you billing service, run by AI, backed by our expert in-house billers. We count the units the way each payer wants, keep the plan-of-care signatures current, and catch the claims that would deny before they go out.

Talk to us, and we will show you which of your therapy claims are denying, and why.

Common questions

Sources: CMS outpatient therapy billing, unit-counting, and plan-of-care certification requirements; CMS annual therapy threshold (2026); AMA timed-code guidance.