Occupational Therapy Billing & RCM

Occupational Therapy billing and revenue cycle, 50-state coverage.

Occupational therapy billing services from ASP-RCM Solutions. 23,499 NPPES occupational therapy billing providers across all 50 states + DC. HIPAA + SOC 2 Type II compliant. Senior partners on every account.

Free occupational therapy billing audit → See 50-state coverage

What good occupational therapy billing execution looks like.

The operating discipline we install on every occupational therapy billing engagement.

8-minute rule + timed code billingOT billing under Medicare 8-minute rule converts treatment minutes to billable units for timed codes (97165-97168 evaluation, 97530, 97535, 97537 treatment). Accurate time tracking is foundational.
GO modifier disciplineAll OT services bill with GO modifier identifying occupational therapy discipline. Missing GO triggers denial.
Plan of Care + recertification cycleMedicare requires physician-signed Plan of Care every 90 days for OT. Recertification timing must be tracked.
KX modifier above therapy thresholdOT has its own separate therapy threshold ($2,480 in 2026). KX modifier and supporting documentation required above threshold.
Pediatric OT + school-based billingPediatric OT may bill state Medicaid EPSDT, school-based services, or commercial. Each requires distinct workflow.
Hand therapy + specialty OT codingHand therapy and other specialty OT carry distinct procedure codes with documentation requirements. Specialty coding depth matters.

The OT unit and threshold map

Three clocks run at once on one occupational therapy patient.

An occupational therapy visit is priced by arithmetic that happens in three separate places, and none of them is the claim. Minutes become units in one place. Allowed charges accrue against an annual threshold in a second. A certification calendar runs in a third. A visit can be clinically perfect and still deny because one of the three was not watched. The exhibit below is built from the CMS rules and the CPT structure that govern them, not from sample data and not from a client.

Sources for the exhibit: the 8-minute ladder, CMS Medicare Claims Processing Manual, chapter 5, time-based code billing; the CY 2026 threshold amounts, CMS therapy services threshold amounts for CY 2026 and the APTA summary of Medicare payment thresholds for outpatient therapy; the targeted medical review threshold and its 2018 through 2028 term, the same APTA summary citing the statutory provision; certification within 30 days of the first treatment day, recertification at least every 90 days, the 14-day verbal order signature and the maximum 90-day certification duration, CMS Medicare Benefit Policy Manual, chapter 15, section 220.1.3; the untimed status of 97165 through 97168, AMA Current Procedural Terminology.

The rules you are billing against

Six numbers an occupational therapy owner should know cold.

Each figure below carries its source. We do not publish benchmarks we cannot point at, and every therapy figure on this page matches the ones on the physical therapy billing and revenue cycle hub and in the outpatient therapy revenue integrity manual for PT, OT and SLP billing.

$2,480

CY 2026 KX threshold, OT only

Occupational therapy accrues against its own annual threshold. Physical therapy and speech-language pathology accrue against a separate combined threshold of the same amount. Occupational therapy does not share with speech-language pathology, and a practice that treats it as one pooled balance will apply the KX modifier at the wrong point in the episode.

CMS therapy services threshold amounts, CY 2026; APTA Medicare payment thresholds for outpatient therapy

$3,000

Targeted medical review threshold

The targeted medical review threshold sits above the KX line and applies for 2018 through 2028, after which it is indexed to the Medicare Economic Index. Crossing it exposes a claim to review by the Supplemental Medical Review Contractor. It is not an automatic audit and it is not a payment cap.

APTA Medicare payment thresholds for outpatient therapy, citing the statutory targeted medical review provision

88 cents

What a CO unit realizes per dollar

When the CO modifier applies, Medicare pays the line at 85 percent of the 80 percent of allowed charges. The 20 percent beneficiary copayment does not move. CMS states the volume discount factor as 0.20 + (0.80 * 0.85), which equals 88 percent. The exposure is 12 percent of allowed charges on the flagged units, not 15 percent of the visit.

CMS CY 2026 Physician Fee Schedule final rule, Federal Register document 2025-19787

8 minutes

The exception that saves the final unit

Since January 1, 2022 the occupational therapist may bill the final 15-minute unit of a multi-unit day without the CO modifier when the therapist independently furnishes at least 8 minutes of that unit, which is more than the 7.5 minute midpoint, regardless of any assistant minutes left over in the same unit.

CMS CY 2022 Physician Fee Schedule final rule, Federal Register document 2021-23972

30 / 90

Certification and recertification days

CMS Medicare Benefit Policy Manual, chapter 15, section 220.1.3

3 levels

OT evaluation complexity

97165 is the low complexity evaluation, 97166 moderate, 97167 high, and 97168 is the re-evaluation of an established plan of care. The level is not a judgment call. It is set by the history component, the number of performance deficits the assessment identifies, and the complexity of the clinical decision making, all of which have to appear in the note.

AOTA, Occupational Therapy Evaluations as Described in the CPT Code Manual; AMA Current Procedural Terminology

The KX threshold is not a cap. Care above the line remains payable when the KX modifier attests that it is medically necessary and the documentation supports it. Note also that CMS counts a beneficiary's incurred expenses toward both thresholds using the fee schedule rate less any applicable multiple procedure payment reduction, so a practice tracking gross charges will believe it has crossed the line before it actually has.

Evaluation coding

97165, 97166, 97167: the level is documented, not chosen.

The occupational therapy evaluation codes replaced a single evaluation code with three complexity levels, and every one of the components in the descriptor has to be documented in order to report the level selected. Practices lose money in both directions here. Defaulting every new patient to 97165 gives away the difference on genuinely complex patients. Defaulting to 97167 without the deficit count and the history component in the note is an unsupported claim that pays now and fails a review later. The determinant that does most of the work is the count of performance deficits, which are inabilities to complete activities because of missing physical, cognitive or psychosocial skills.

Code and level	Occupational profile and history component	Performance deficits identified	Clinical decision making and typical time
97165Evaluation, low complexity	A brief history, including review of medical or therapy records relating to the presenting problem.	1 to 3	Low complexity. Analysis of the occupational profile and of data from problem-focused assessments, with a limited number of treatment options considered. No comorbidities affecting occupational performance. Typically 30 minutes face to face.
97166Evaluation, moderate complexity	An expanded review of medical or therapy records plus additional review of physical, cognitive or psychosocial history related to current functional performance.	3 to 5	Moderate analytic complexity. Analysis of data from detailed assessments with several treatment options considered. The patient may present with comorbidities affecting occupational performance. Typically 45 minutes face to face.
97167Evaluation, high complexity	Review of medical or therapy records plus extensive additional review of physical, cognitive or psychosocial history related to current functional performance.	5 or more	High analytic complexity. Analysis of data from comprehensive assessments with multiple treatment options considered. The patient presents with comorbidities affecting occupational performance. Typically 60 minutes face to face.
97168Re-evaluation of an established plan	An update to the initial occupational profile reflecting changes in condition or environment that affect future interventions or goals.	n/a	An assessment of changes in functional or medical status with a revised plan of care. Performed when there is a documented change in functional status or a significant change to the plan is required. Typically 30 minutes face to face.

Descriptor content from AOTA, Occupational Therapy Evaluations as Described in the CPT Code Manual, reproducing the AMA CPT descriptors for 97165 through 97168. Performance deficits are defined there as the inability to complete activities due to a lack of skills in the physical, cognitive or psychosocial categories, and the plan of treatment is expected to reflect assessment of each identified deficit. All four codes are untimed service-based codes: one unit for the date of service regardless of duration, and their minutes stay out of the 8-minute ladder. Run the ladder on your own minutes with the therapy units calculator for the 8-minute rule and the CO modifier de minimis test.

OTA payment and the CO modifier

The CO modifier, and the 8 minutes that decide the last unit.

Beginning in CY 2022, section 1834(v)(1) of the Social Security Act requires a 15 percent payment reduction for outpatient occupational therapy services furnished in whole or in part by an occupational therapy assistant. CMS created the CO modifier for OTA services in the CY 2019 Physician Fee Schedule final rule and required it on claims for dates of service beginning January 1, 2020. The reduction bites on the Medicare payment and not on the beneficiary copayment, which is why the number a practice should plan against is 88 cents on the dollar rather than 85. The modifier is not triggered by the assistant walking into the room. It is triggered by a threshold, and there is an exception on the final unit that a well-run practice bills to and a badly run one gives away.

The 88 percent factor is CMS arithmetic, not ours. Sources: CY 2026 PFS final rule, Federal Register document 2025-19787, which states payment for services carrying CQ or CO is made at 85 percent of the 80 percent of allowed charges; CY 2022 PFS final rule, Federal Register document 2021-23972, for the de minimis standard and the final-unit exception and the worked example.

The documentation that defends the split

Every assistant-involved unit is a two-sided assertion: who delivered which minutes, and whether the occupational therapist independently met the billing threshold on the final unit. If the note cannot answer both, the modifier decision cannot be defended on review, and the practice is exposed in both directions at once, an unclaimed unit or an unsupported one. Minute capture keyed to the individual delivering the care, rather than to the visit, is what makes the denominator of the de minimis calculation exist at all. A pre-bill prompt on multi-unit days that asks whether the therapist independently furnished 8 minutes of the final unit, and records the answer, is what makes the exception billable rather than theoretical. Supervision level is set by the practice act where the visit happens and by the setting, so it belongs in a rule per licensed location checked at scheduling. And an assistant cannot carry a plan of care that is not certified, which means a CO question on an uncertified episode is the wrong argument to be having.

Two disciplines, one patient

What is shared and what is not when a patient gets both PT and OT.

This is the single most common source of avoidable error in a multi-discipline therapy practice, because the instinct is wrong in both directions. Some things that feel separate aggregate. Some things that feel shared do not. Getting the list backwards produces a KX modifier applied at the wrong point in one episode and a payment reduction nobody modelled in another.

Mechanic	Shared across PT and OT	What that means in practice
The annual threshold accrualKX modifier and targeted medical review	No	Occupational therapy accrues against its own $2,480 for CY 2026. Physical therapy accrues with speech-language pathology against a separate combined $2,480. A patient in both disciplines has two running balances that cross at different moments, so the KX decision has to be made per discipline rather than per patient.
The timed-minute poolThe 8-minute ladder	No	The ladder runs on total timed minutes for the discipline for the date of service. Physical therapy minutes and occupational therapy minutes are counted in separate pools, and merging them inflates the unit count on a day when the patient genuinely saw both.
The discipline modifierGP against GO	No	Every occupational therapy line carries GO and every physical therapy line carries GP. In a practice running both, the modifier has to be driven from the rendering therapist record rather than typed per claim, because a hand-keyed modifier on a mixed day is a denial waiting for the next busy week.
The plan of care and certificationThe 30 and 90 day clock	No	Each discipline runs its own plan of care with its own certification within 30 days of that discipline's first treatment day and its own recertification at least every 90 days. Two calendars, not one, and the second one is the one that slips.
The multiple procedure payment reductionPractice expense on the second and later services	Yes	This one does aggregate. The reduction applies when multiple always-therapy services are billed on the same date of service for one beneficiary by the same practitioner or facility under the same national provider identifier, whether the services are one discipline or several. A physical therapy and occupational therapy session on the same day under one identifier aggregates, the practice expense component of everything other than the highest line is reduced by 50 percent, and reordering codes on the claim recovers nothing.

Sources: CY 2026 threshold amounts from CMS therapy services threshold amounts for CY 2026 and the APTA summary; discipline modifiers and the therapy plan of care from CMS Medicare Benefit Policy Manual chapter 15; the therapy multiple procedure payment reduction, including its cross-discipline reach, its 50 percent practice expense reduction and its exclusion of add-on and contractor-priced codes, from the CY 2014 PFS final rule that sets out the history and the exclusions. The full treatment of both mechanics sits on the physical therapy billing and revenue cycle hub.

Revenue leakage taxonomy

The five places occupational therapy revenue actually leaks.

Occupational therapy denials are not random. They cluster into five drivers, and all five are visible before the claim is ever submitted, because the information already sits in the treatment note, the certification calendar, the running threshold accrual and the minute record. This is the taxonomy we work against on every occupational therapy engagement.

Leakage driver	How the dollars go missing	The pre-bill control we install	Fixable pre-bill
Evaluation level defaulted97165 against 97166 against 97167	Every new patient gets the same evaluation code because the level is treated as a habit rather than as a documented finding. Defaulting low gives away the difference on complex patients. Defaulting high produces claims that pay now and fail review later, because the deficit count and the history component are not in the note to support them.	Evaluation level driven from the documented performance deficit count and the history component, checked pre-bill, so the code follows the note instead of the note being asked to follow the code.	Yes
One pooled threshold balanceOT tracked with PT and SLP	The practice runs a single running total across all three disciplines, so the occupational therapy balance is wrong in one direction and the combined physical therapy and speech-language pathology balance is wrong in the other. The KX modifier then goes on too early on one episode and too late on another, and the late one denies.	Two running accruals per patient, one for occupational therapy and one for the combined physical therapy and speech-language pathology line, tracked on the fee schedule rate less any applicable multiple procedure payment reduction rather than on gross charges.	Yes
Timed unit miscount8-minute rule arithmetic	The record system rounds each CPT code on its own instead of summing the day's total timed minutes for the discipline. A visit with 18 minutes of one timed service and 20 of another is 38 total timed minutes, which supports 3 units. Per-code rounding bills 1 plus 1 and the third unit is simply never billed.	A charge scrub that recomputes units from total timed minutes per discipline per day and refuses the claim when the billed count and the documented minutes disagree, with untimed evaluation codes excluded from the pool.	Yes
The CO decision unsupportedAssistant minutes not attributed	The note records visit minutes rather than minutes by person, so the de minimis calculation has no denominator. The practice then either applies CO defensively to units that did not need it and gives away 12 percent of allowed charges, or omits it from units that did and carries an unsupported claim.	Timed-minute capture keyed to the individual delivering the care, plus a pre-bill prompt on multi-unit days asking whether the therapist independently furnished 8 minutes of the final unit, with the answer recorded.	Yes
Certification lapsedPlan of care timing	The plan of care is never certified inside the 30-day window, or the 90-day recertification slips while treatment continues. Every visit delivered after the lapse is exposed, and the denial arrives weeks after the chair time is spent and the therapist has moved on.	A certification calendar per patient and per discipline with the 30-day signature and the 90-day recertification date surfaced to the front desk, plus a hold on billing for visits that fall outside a certified plan.	Yes

The table describes ASP-RCM's operating taxonomy and the controls we install. It does not assert denial frequencies. Denial mix is measured per practice during the free 30-day audit against the practice's own last 90 days of claim data.

Occupational therapy billing FAQ

Questions occupational therapy owners actually ask.

Does occupational therapy share the KX threshold with speech-language pathology?

No, and this is the single most expensive misunderstanding in multi-discipline therapy billing. For calendar year 2026 the threshold is $2,480 for physical therapy and speech-language pathology services combined, and a separate $2,480 for occupational therapy services. A patient receiving occupational therapy and speech-language pathology is running two independent balances, not one shared one, and they will cross at different points in the episode. Once a patient's allowed charges pass the applicable line, later claims for that discipline must carry the KX modifier, which attests that the care is still medically necessary and that the documentation supports it. The threshold is not a cap.

What is the CO modifier and what does it actually cost?

The CO modifier identifies an outpatient occupational therapy service furnished in whole or in part by an occupational therapy assistant. Beginning in CY 2022, section 1834(v)(1) of the Social Security Act requires a 15 percent payment reduction on those services, and CMS created the modifier in the CY 2019 Physician Fee Schedule final rule with a claims requirement from January 1, 2020. The practical cost is smaller than 15 percent and it is worth modelling correctly. Medicare pays outpatient therapy at 80 percent of the allowed charge, with the remaining 20 percent as beneficiary copayment. When CO applies, payment is made at 85 percent of that 80 percent, so the copayment does not move and CMS states the volume discount factor as 0.20 + (0.80 * 0.85), which equals 88 percent. Exposure is 12 percent of allowed charges on the flagged units, not 15 percent of the visit.

When does the de minimis standard force the CO modifier onto a unit?

The CO modifier applies when the occupational therapy assistant furnishes more than 10 percent of a service or of a 15-minute unit of service. Since January 1, 2022 there is an exception worth billing to: the therapist may bill the final 15-minute unit in a multi-unit scenario without the modifier when the therapist independently furnishes at least 8 minutes of that unit, which is more than the 7.5 minute midpoint, regardless of any assistant minutes left over in the same unit. CMS worked the example in the CY 2022 final rule. The therapist provides 23 minutes and the assistant provides 20 minutes of the same service, the 43 total minutes support 3 units, one bills without the modifier, one bills with it, and the third bills without it because the therapist's remaining 8 minutes meet the billing threshold on their own.

How do I choose between 97165, 97166 and 97167?

The level is determined by three documented components rather than by clinical impression. The first is the occupational profile and medical and therapy history: a brief history for 97165, an expanded review with additional physical, cognitive or psychosocial history for 97166, and an extensive additional review for 97167. The second is the count of performance deficits the assessment identifies, meaning inabilities to complete activities because of missing physical, cognitive or psychosocial skills: 1 to 3 for low complexity, 3 to 5 for moderate, 5 or more for high. The third is the complexity of the clinical decision making, which rises from a limited number of treatment options with no comorbidities affecting occupational performance, through several options with possible comorbidities, to multiple options with comorbidities present. Typical face to face time runs 30, 45 and 60 minutes. Each component in the descriptor has to be documented in order to report the level selected, and 97168 covers the re-evaluation of an established plan of care.

How often does an occupational therapy plan of care need to be certified?

The plan of care must be certified by a physician or non-physician practitioner within 30 days of the first day of treatment, and recertified at least every 90 days while care continues. A verbal order has to be followed by a signature within 14 days to be timely, and a practitioner may certify for any duration up to 90 calendar days. Visits delivered outside a certified plan are exposed. In a practice delivering both occupational therapy and physical therapy, each discipline runs its own plan and its own certification calendar, which is why the second calendar is the one that slips.

What changes when one patient receives both physical therapy and occupational therapy?

Four things stay separate and one aggregates, and the instinct is usually backwards on both counts. The threshold accrual stays separate, because occupational therapy has its own line and physical therapy shares a different one with speech-language pathology. The timed-minute pool stays separate, because the 8-minute ladder runs per discipline per date of service. The discipline modifier stays separate, GO on occupational therapy lines and GP on physical therapy lines. The plan of care and its certification calendar stay separate, one per discipline. What aggregates is the multiple procedure payment reduction: it applies when multiple always-therapy services are billed on the same date for one beneficiary by the same practitioner or facility under the same national provider identifier, whether the services are one discipline or several, so a physical therapy and occupational therapy session on the same day under one identifier is treated as one high-unit day.

Top occupational therapy billing markets by NPPES org count.

State-level RCM guides for the largest occupational therapy billing markets in the U.S.

Florida2,353 orgs → Texas1,564 orgs → New York1,430 orgs → California1,230 orgs → New Jersey993 orgs → Maryland939 orgs → Illinois931 orgs → North Carolina912 orgs →

View all 50 state guides →

Free 30-day audit for occupational therapy billing providers.

Send us your last 90 days of claim data. We assess realization, denial patterns, and operational discipline. Written 4-page report yours to keep.

Request audit →Talk to a senior partner

Occupational Therapy billing by state.

Dedicated Occupational Therapy billing and credentialing field guides for 51 states. Each state guide opens into its city-level guides with local payer, Medicaid, and credentialing detail.