By Brandon Seigel, Chief Problem Solver · September 1, 2026 · 8 min read
Start with the evaluation codes
OT evaluations are billed by complexity: 97165 (low), 97166 (moderate), and 97167 (high), with 97168 for re-evaluations. Complexity is driven by the patient's history, the number of performance deficits, and clinical decision making — not by how long the visit took.
The most common problem we find in audits is under-coding. Therapists pick low complexity to feel safe, even when their documentation supports moderate or high. That is money left on the table on every new patient.
Know your most-used treatment codes
Most OT visits are built from a handful of timed codes:
- 97530 — Therapeutic activities
- 97535 — Self-care and home management training
- 97110 — Therapeutic exercise
- 97112 — Neuromuscular re-education
- 97533 — Sensory integrative techniques
- 97140 — Manual therapy
The 8-minute rule and timed units
Medicare and many commercial payers follow the 8-minute rule: a timed code needs at least 8 minutes to bill one unit. Total timed minutes determine total units, then units are split across codes.
Documentation must show start and stop times or total timed minutes for each code. If your notes don't show it, the payer can deny it — even if the care happened.
Pediatric OT has its own traps
Pediatric OT practices often deal with Medicaid and managed Medicaid plans. That means authorizations, visit limits, and plan-specific rules. A lapsed authorization is one of the most expensive mistakes a pediatric practice can make, because the visits usually can't be recovered.
This is why eligibility and authorization tracking needs a system — not a spreadsheet someone checks when they have time.
What strong OT billing looks like
Claims go out every business day. Payments post every business day. Denials get worked while they are still easy to fix. And someone with real coding expertise reviews patterns before they become write-offs.
Quick answers
What CPT codes do occupational therapists use most?
Evaluations use 97165, 97166, and 97167 by complexity, and 97168 for re-evaluation. Common treatment codes include 97530, 97535, 97110, 97112, 97533, and 97140.
Does the 8-minute rule apply to occupational therapy?
Yes, for Medicare and many commercial payers. A timed code needs at least 8 minutes to bill one unit, and total timed minutes determine total billable units.
See exactly what's included in our medical billing services for therapy practices, how our percentage-of-collections pricing works, or browse common questions from practice owners.
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