Incident-To Billing: Medicare Rules and Requirements (2026)

Incident-to billing lets a service performed by a nurse practitioner, physician assistant or other auxiliary staff in an office be billed under the supervising physician's NPI, so Medicare pays 100% of the fee schedule amount instead of the 85% an NPP gets when billing under their own number. It applies only when the physician started the course of treatment, stays actively involved, and directly supervises the visit, either from the office suite or, from 2026, by real-time audio-video.

What incident-to billing means

Medicare Part B pays for services "furnished incident to a physician's or other practitioner's services" when they're part of the physician's own professional service, commonly furnished in an office, and included in the physician's bill (Benefit Policy Manual, ch. 15, §60). The person doing the work can be a nurse, medical assistant, therapist or an NPP such as an NP, PA or clinical nurse specialist.

The payment difference is the reason practices care. NPs, PAs and CNSs billing under their own NPI are paid 85% of what a physician would get under the Physician Fee Schedule (Claims Processing Manual, ch. 12, §§110 and 120). The same visit billed incident-to a physician pays the full amount.

Incident-to requirements

Every requirement must be met on every date of service. Miss one and the service belongs under the performing NPP's own NPI.

1. A noninstitutional setting

Incident-to services must be furnished in a noninstitutional setting to noninstitutional patients (42 CFR 410.26(b)(1)). That means a physician office, a clinic or the patient's home. For hospital patients and SNF patients in a covered stay, there's no Part B incident-to coverage (Benefit Policy Manual, ch. 15, §60.1B).

2. The physician started the course of treatment

CMS requires "a direct, personal, professional service furnished by the physician to initiate the course of treatment," followed by "subsequent services by the physician of a frequency that reflects the physician's continuing active participation in and management of the course of treatment" (§60.2). In practice:

• New patients are seen first by the physician.
• A new problem in an established patient starts a new course of treatment, which the physician has to initiate.
• Follow-ups within an existing plan can be done by the NPP and billed incident-to, as long as the physician keeps seeing the patient often enough to show ongoing management.

3. Direct supervision, in person or virtual

Direct supervision in the office means the supervising practitioner is "present in the office suite and immediately available to furnish assistance and direction throughout the performance of the service." It doesn't mean being in the same room (42 CFR 410.32(b)(3)(ii)).

For services from January 1, 2026, CMS made virtual direct supervision permanent: presence "may include virtual presence through audio/video real-time communications technology (excluding audio-only) for services without a 010 or 090 global surgery indicator" (42 CFR 410.26(a)(2); MLN Matters MM14315). The supervisor has to be available on live video for the whole service; a phone line isn't enough.

Two categories need only general supervision, where the supervising practitioner doesn't have to be present or immediately available (42 CFR 410.26(b)(5)):

• Behavioral health services furnished by auxiliary personnel incident-to. How that works for therapists, and why LCSWs, LMFTs and LPCs can't have services billed incident to themselves, is covered in incident-to in behavioral health.
• Designated care management services.

4. The right billing NPI

The supervising practitioner doesn't have to be the physician who treats the patient more broadly, but "only the supervising physician (or other practitioner) may bill Medicare for incident to services" (42 CFR 410.26(b)(5)). If Dr. A wrote the plan and Dr. B supervised today, the claim goes under Dr. B.

5. The staff and the expense belong to the billing practice

Auxiliary personnel can be employees, leased employees or independent contractors of the physician or the billing entity. They must meet state licensure rules and not be excluded from federal programs (42 CFR 410.26(a)(1)). The service must be an expense to the billing practice (§60.1B).

Is this visit incident-to?

Walk a visit through the flow:

Incident-to vs split/shared visits

Split (or shared) billing is the facility-setting counterpart. In a hospital or SNF, where incident-to is prohibited, a physician and an NPP in the same group can split an E/M visit, and the one who performed the substantive portion bills it with modifier FS. From 2024 the substantive portion is more than half the total time, or a substantive part of the medical decision making (Claims Processing Manual, ch. 12, §30.6.18). Office visits can't be billed split/shared.

Staff visits: 99211

When a nurse or medical assistant (not an NPP) provides an E/M service incident-to, the physician bills 99211 (Claims Processing Manual, ch. 12, §30.6.4). The same supervision and course-of-treatment rules apply. When an NPP furnishes the visit incident-to, the physician bills the E/M level the NPP's work supports.

How to set up incident-to correctly

1. Schedule new patients and new problems with the physician. Build it into intake so NPPs don't start courses of treatment that later get billed incident-to.
2. Record who supervised. Note the supervising practitioner, and for virtual supervision, that real-time audio-video was available, on every incident-to date of service.
3. Bill under the supervisor's NPI and name the NPP or staff member who performed the service in the note.
4. Keep the physician involved. Schedule periodic physician visits that show active management.
5. Check commercial payers separately. Incident-to is a Medicare rule; many commercial plans don't recognize it or set their own terms.

Pricing NPP visits across your code list? Compare full and 85% rates for every code at your locality.

FAQ

What is an example of incident-to billing?

A physician sees a new patient with hypertension and sets a treatment plan. Six weeks later the practice's NP sees the patient for a scheduled follow-up while the physician is in the office suite, and the visit is billed as 99213 under the physician's NPI at 100% of the fee schedule.

What documentation is required for incident-to billing?

The note should show the physician's initial service that started the course of treatment, the NPP or staff member who performed today's service, the supervising practitioner on site or on live video, and evidence of the physician's ongoing involvement. The claim goes under the supervising practitioner's NPI.

What are the CMS incident-to billing guidelines for 2026?

The core rules haven't changed: noninstitutional setting, physician-initiated course of treatment, direct supervision and billing under the supervisor. The 2026 change is that direct supervision through real-time audio-video is now permanent, except for services with a 010 or 090 global period.

Is incident-to billing only for Medicare?

Incident-to is a Medicare Part B rule. Commercial and Medicaid payers set their own policies, and many don't allow it. Check each contract.

Can a nurse practitioner bill incident-to a physician for a new patient?

No. The physician has to personally furnish the service that starts the course of treatment. The NP can see a new patient and bill under their own NPI at 85%.

Does incident-to apply to physical therapy?

Therapy in a physician's office can be incident-to, but the service and the person furnishing it must meet the standards that apply to physical therapists (42 CFR 410.60(a)(3)(iii)). See the physical therapy CPT codes guide.

Keep reading

• Mental health billing: behavioral health codes, provider-type payment and incident-to under general supervision.
• Psychotherapy CPT codes: the session, evaluation and crisis codes therapists bill.
• Physical therapy CPT codes: therapy in physician offices and PTA rules.
• Modifier 25 vs 59: separately identifiable visits on procedure days.
• What is an RVU?: how the 100% and 85% amounts are calculated.
• RVU calculator: any code's rate at your locality.
• Codes in this guide: 99211 99212 99213 99214 99215

Sources: Medicare Benefit Policy Manual, Pub. 100-02, ch. 15, §§60–60.3 (Rev. 13889, July 30, 2026); 42 CFR 410.26 and 410.32(b)(3)(ii) (eCFR, current Oct 1, 2026); MLN Matters MM14315, CY 2026 PFS final rule summary; CMS CY 2026 PFS final rule fact sheet (Oct 31, 2025); Medicare Claims Processing Manual, Pub. 100-04, ch. 12, §§30.6.4, 30.6.18, 110 and 120. Verified October 6, 2026.