Billing Codes for Physical Therapy: Medicare Guide (2026)

Physical therapy is billed with an untimed evaluation code (97161, 97162 or 97163, or 97164 for a re-evaluation) plus 15-minute timed treatment codes such as 97110, 97112, 97140 and 97530, each with the GP modifier. Medicare turns the day's timed minutes into units with the 8-minute rule, then cuts practice-expense payment on every unit after the first.

Physical therapy evaluation codes: 97161–97164

The initial evaluation is reported once, at one of three complexity levels. The level reflects how much the patient's history, body systems, clinical presentation and decision-making demand of the therapist, not the minutes spent.

A re-evaluation (97164) is separately payable when the therapist's assessment shows a significant improvement, decline or other change in the patient's condition or function that the plan of care didn't anticipate (Benefit Policy Manual, ch. 15, §220). Routine reassessment during treatment isn't a re-evaluation.

Timed physical therapy billing codes

These are the codes billed most often in outpatient PT. Each is reported in 15-minute units of direct, one-on-one time.

97110 vs 97530

The two codes can involve the same equipment and even the same movements. What separates them is the goal the note documents:

• 97110 targets a single impairment: building strength in a muscle group, restoring range of motion at a joint, improving endurance.
• 97530 targets a functional task that combines several movements: getting up from a chair, lifting a box from the floor, reaching into a cabinet.

A squat done to strengthen the quadriceps is 97110. A sit-to-stand practiced so the patient can get off the toilet safely is 97530. If the note says "therapeutic activities" but describes isolated strengthening, the documentation supports 97110.

Can 97110 and 97530 be billed on the same day? Yes, when both were performed and the minutes support the units. If an NCCI edit pairs two timed codes you delivered in separate, unmingled time blocks, CMS allows modifier 59 or XE to show they were distinct (MLN1783722). See modifier 25 vs 59.

Timed vs untimed codes and the 8-minute rule

Untimed codes (evaluations, re-evaluations, unattended modalities) are billed as one unit per day. For timed codes, Medicare adds up all timed minutes for the day and converts the total into units (Claims Processing Manual, ch. 5, §20.2):

Assign the units to the codes with the most minutes. Drag the minutes below to see how a 41-minute visit splits:

Here 41 minutes supports only 3 units for four blocks of time. 97110 earns one unit for its first full 15 minutes, 97140's 10 minutes beat the 8 left over on 97110 and 97530, and the last unit goes to one of those two tied codes; the other's minutes are documented but not billed. Commercial payers that follow the AMA's per-code rule may count differently. Use the 8-minute rule calculator for any combination.

Untimed modalities: 97010, 97014 and G0283

• 97010 (hot or cold packs) has a bundled status on the Medicare fee schedule. It isn't paid separately; payment is included in other services that day.
• 97014 (unattended electrical stimulation) has status I: not valid for Medicare claims.
• G0283 is the HCPCS code Medicare uses instead, for unattended electrical stimulation other than wound care as part of a therapy plan of care. It's untimed: one unit per day.

The modifiers every PT claim needs

GP. CMS requires GN, GO or GP on every "always therapy" service, and only one of them per line. GP marks services under a physical therapy plan of care.

CQ. When a physical therapist assistant furnishes a service "in whole or in part," the line also carries CQ (always paired with GP) and Medicare's payment is reduced by 15% for dates of service from January 1, 2022 (42 CFR 410.60(a)(4)). The allowed amount and the patient's 20% coinsurance are unchanged: on a $100 allowed amount, coinsurance is $20 and Medicare pays $68 instead of $80 (Transmittal R11129CP). "In part" means the assistant's minutes exceed 10% of the service's total. One exception: for the last 15-minute unit of the day, if the therapist personally provided 8 or more minutes, no CQ is needed. The 15% reduction is taken last, after the MPPR (Claims Processing Manual, ch. 5, §20).

CQ applies to therapists in private practice and to institutional providers paid at PFS rates. It doesn't apply to therapy billed by or incident to a physician or NPP, and it doesn't apply to critical access hospitals. In private practice, a PTA may work under the PT's general supervision (42 CFR 410.60(c)(2)).

KX. Once a patient's incurred therapy expenses for the year pass the threshold, add KX to attest that continued care is medically necessary and documented. For 2026 the thresholds are $2,480 for PT and speech-language pathology combined and $2,480 for occupational therapy (MLN Matters MM14315). Lines over the threshold without KX are denied.

Multiple procedure payment reduction

Medicare pays the full practice-expense amount only for the unit or procedure with the highest PE payment that day. Every other unit, including second and third units of the same code, gets 50% of its practice-expense payment. Work and malpractice are always paid in full. The reduction applies across PT, OT and SLP on the same day (Claims Processing Manual, ch. 5, §10.7).

Run your own visit through the therapy MPPR calculator.

Plan of care and certification

1. Evaluate and write the plan. The plan of care sets goals, the type, amount, frequency and duration of treatment.
2. Get it certified. A physician or NPP signs and dates the plan within 30 days of the first treatment day, evaluation included. A verbal certification must be signed within 14 days (Benefit Policy Manual, ch. 15, §220.1.3).
3. Use the written-order exception when it applies. If the record has a written order or referral and you can show the plan was sent to the ordering practitioner within 30 days of the evaluation, no signature is needed for the initial certification (42 CFR 424.24(c)(5)).
4. Recertify at least every 90 days if treatment continues, with documentation of the continuing need.

Pricing a whole PT code list for your locality? A fee sheet does it in one pass.

FAQ

What are the billing codes for physical therapy?

Evaluations 97161, 97162 and 97163 (low, moderate and high complexity), re-evaluation 97164, and timed treatment codes such as 97110 (therapeutic exercise), 97112 (neuromuscular re-education), 97116 (gait training), 97140 (manual therapy), 97530 (therapeutic activities) and 97535 (self-care training). Medicare adds GP to each line.

Is billing code 97530 OT or PT?

Both. 97530 and most other 97xxx treatment codes can be billed by physical or occupational therapists. The modifier shows whose plan of care the service falls under: GP for PT, GO for OT.

Is billing code 97110 PT or OT?

Both, like 97530. Use GP when it's furnished under a PT plan of care and GO under an OT plan.

Can 97110 and 97530 be billed together?

Yes, when both services were performed and the day's total timed minutes support the units. Document the purpose of each so the note shows they were different services.

Is billing code 97140 PT or OT?

Either discipline can bill 97140 when it's within their scope under state law. It's a 15-minute timed code like the others.

How many units can I bill for 45 minutes of therapy?

Three. 38 to 52 total timed minutes supports 3 units under Medicare's rule. Assign them to the codes with the most minutes.

Keep reading

• 8-minute rule calculator: minutes to units for any mix of timed codes.
• Therapy MPPR calculator: payment after the practice-expense reduction.
• Incident-to billing: when therapy in a physician's office is billed under the physician.
• Modifier 25 vs 59: when 59 or XE belongs on therapy lines.
• What is an RVU?: why practice expense drives the MPPR.
• Modifiers: GP, KX, CQ, 59.
• Codes in this guide: 97161 97162 97163 97164 97110 97112 97116 97140 97530 97535 97010 97014 G0283

Sources: Medicare Claims Processing Manual, Pub. 100-04, ch. 5, §10.7, §20.1 and §20.2; Medicare Benefit Policy Manual, Pub. 100-02, ch. 15, §220.1.3 and §220.3; 42 CFR 410.60 and 424.24(c) (eCFR, current Oct 1, 2026); MLN Matters MM14315, CY 2026 PFS final rule summary; MLN1783722 (April 2026); status indicators from CMS RVU26D. Verified October 6, 2026.