How to Dispute a Physical Therapy Bill

PT billing runs on 15-minute units

Physical therapy is billed in units, each representing roughly 15 minutes of a specific service — therapeutic exercise, manual therapy, electrical stimulation, ultrasound. Two or more services in a session means multiple unit lines. The billing rule is strict: you can't bill a unit unless at least half the time unit was actually provided. Sessions billed for more time than occurred are a common error.

Each service also has its own CPT code and its own unit count, which is where errors cluster. A single hour-long session can produce six or eight line items across three or four codes. That's normal — but each line must match a service you actually received, and the combined units must fit the session clock. When they don't, you're usually looking at padding, not coincidence.

Verify units against your session time

Ask for the itemized bill and add up the billed units. A 45-minute session should generally produce three units of one or two services. If the bill shows four or five units for a 45-minute appointment, or codes you for services you didn't receive (like electrical stimulation you never had), dispute those lines in writing.

• More 15-minute units than the session length supports.
• Codes for modalities (electrical stim, ultrasound) you didn't receive.
• Duplicate charges across consecutive visits.
• The same visit billed by both a clinic and a facility.
• Denied visits after your plan's session cap.

Denied visits and coverage caps

Many plans limit PT visits per year or require approval after a set number of sessions. When a visit is denied, the provider can bill you directly for it. Dispute denials by appealing with your therapist's notes and progress documentation — continued functional improvement is the standard most plans use. Request a medical-necessity review if a cap is triggered.

The appeal clock matters: most plans give you 180 days from the denial. Ask your therapist for a letter of medical necessity and the objective measures (range of motion, strength scores, pain scales) showing improvement since the last approved visit. Plans deny caps reflexively at first — the appeal is where the coverage decision actually gets made.

Out-of-network PT and cash practices

If your therapist was out-of-network, you may be balance-billed. Verify the out-of-network rate your plan allows and negotiate the difference. Many cash-based PT practices publish per-visit rates — ask whether the billed charge exceeds the practice's standard self-pay rate.

Before you start a new PT program, confirm the clinic's network status with your insurer — not with the front desk, whose job is filling the schedule. Out-of-network PT is a growing category, and a plan that covers 20 in-network visits may cover none out-of-network.

1. 1Request the itemized bill with per-visit unit counts.
2. 2Compare total units to your actual session times.
3. 3Match each modality code to what you received.
4. 4Appeal denied visits with therapist progress notes.
5. 5Negotiate out-of-network balances or cash rates.

What if I wasn't told about a cost?

If your clinic didn't disclose that a service wasn't covered before providing it, you can dispute on disclosure grounds: ask the clinic to write off the charge or rebill correctly, and note in your letter that you were not informed a balance would be due.

Getting PT bills right going forward

Confirm coverage and visit limits before starting a PT program, ask each session's billed units at the front desk, and get your therapist to document progress notes you can use in an appeal. A few minutes of verification per visit prevents most PT billing disputes.