Multispecialty Group Billing Services · 2026 Playbook

Split/Shared, Incident-To, and MVPs: Getting Attribution Right in 2026

In a multispecialty group, the hard question is never whether a visit is billable. It is whose NPI gets the credit. Get that wrong and you overpay on audit, misfire your quality scores, and leave clean money in denials.

The short answer

For a split/shared visit in a facility, bill under the clinician who performed the substantive portion as defined by the CY2026 Medicare Physician Fee Schedule: more than half of the total time, or the practitioner who performed the medically necessary MDM. Append modifier FS. For an incident-to visit in the office, the visit stays under the supervising physician only when the plan of care, direct supervision, and established-patient rules in Benefit Policy Manual Ch. 15 §60 all hold. Everything else routes to the rendering clinician.

§ CY2026 PFS substantive portion § Benefit Policy Manual Ch.15 §60 § Modifier FS § MIPS Value Pathways 2026

Three rules, three owners

Same visit, different NPI, different rulebook

Split/shared and incident-to look alike at the front desk and behave nothing alike in the ledger. The setting decides which one you are even allowed to use.

01 Facility setting

Split / Shared

A physician and a non-physician practitioner (NPP) in the same group each personally furnish part of one E/M visit in a facility (hospital, on-campus/off-campus outpatient). Billed under whoever did the substantive portion.

CY2026 Medicare PFS · Modifier FS required

02 Non-facility / office

Incident-To

An NPP delivers care in the office under a physician's established plan of care and direct supervision. Billed 100% under the physician's NPI, but only for established patients with no new problem.

Benefit Policy Manual Pub.100-02, Ch.15 §60

03 Quality & payment

MVPs (2026)

MIPS Value Pathways attribute quality, cost, and improvement measures to the billing clinician or group. Whoever the claim credits is who the specialty-specific MVP measures follow.

Quality Payment Program · MVP performance year 2026

The 2026 pivot point

What "substantive portion" actually means now

Under the CY2026 Physician Fee Schedule, a group has two defensible ways to decide who owns a split/shared E/M. Pick one per visit, document it, and stay consistent.

OPTION A More than half the time

Physician · >50% of total time NPP

Total time = combined qualifying time of both clinicians on the date of service, counted once (no double-counting overlap).
The clinician with the greater share bills the visit.
Critical care (99291/99292) is time-only under this method.

OPTION B Medically necessary MDM

The clinician who performed the substantive part of the medical decision making bills the visit.
That clinician must personally perform the two of three MDM elements that drive the level, and the note must show it.
Whichever method you choose, append modifier FS to flag the service as split/shared.
Reviewing another clinician's note is not the same as performing the MDM.

The infographic checklist

Attribute every shared visit across the group, in four passes

Run this before the claim leaves the building. If any box cannot be checked honestly, the visit routes to the rendering clinician, not the physician.

Before the visit

Setting & eligibility

Confirm place of service. Facility POS points to split/shared; office POS points to incident-to. They are not interchangeable.

Both clinicians share the same group TIN and are eligible to bill Medicare.

For incident-to only: established patient, no new problem, and a physician's plan of care already on file.

During the visit

Who did what

Direct supervision present for incident-to: the physician is in the office suite and immediately available (not necessarily in the room).

Track qualifying time per clinician if you will attribute by time. Count the date's total once.

Note who owns the MDM if you will attribute by decision making instead of time.

In the documentation

Proof, not assertion

Both clinicians document their own work and sign. A borrowed attestation is not personal performance.

The note names the substantive-portion method used (time or MDM) and supports it.

Incident-to charts tie back to the physician's established plan for that condition.

On the claim

Attribution & submission

Billing NPI matches the substantive-portion owner (split/shared) or the supervising physician (valid incident-to).

Modifier FS appended on every split/shared E/M line.

Confirm the credited clinician's MVP. The attributed NPI is who your 2026 quality measures follow.

Side by side

Split/shared vs incident-to, at a glance

Test	Split / Shared	Incident-To
Where it applies	Facility (hospital, outpatient)	Non-facility office only
Who bills	Clinician doing the substantive portion	Supervising physician (100%)
Patient status	New or established	Established patient, no new problem
Supervision	Both personally furnish part of the visit	Direct supervision in the office suite
Key modifier	FS on the E/M line	None specific to incident-to
Governing rule	CY2026 Medicare PFS	Benefit Policy Manual Ch.15 §60
If a box fails	Route the visit to the rendering clinician's own NPI at their fee-schedule rate.

The routing logic

One visit, four questions, one owner

Facility or office?Setting selects the rulebook before anything else.

Rules met?Plan of care + supervision (office) or shared performance (facility).

Who did the work?Substantive portion by time or MDM; or the supervising physician.

✓

Bill & flag.Correct NPI, modifier FS if split/shared, MVP checked.

Why attribution is a quality problem too

Your billing NPI is also your MVP scorecard

Under MIPS Value Pathways for the 2026 performance year, quality, cost, improvement activities, and promoting interoperability all follow the clinician or group the claim credits. In a multispecialty group that mixes specialties across one visit, sloppy attribution silently pulls the wrong measures onto the wrong clinician, and the score shows up a year later when it is too late to fix.

Getting split/shared and incident-to attribution right is not just clean revenue. It is the input that decides whether your 2026 MVP reporting reflects the care your clinicians actually delivered.

QualitySpecialty-aligned measures follow the attributed NPI

CostEpisode & total-cost measures ride the billing clinician

Improvement ActivitiesCredited at the reporting level you attribute to

Promoting InteroperabilityTied to the same clinician/group identity

Where multispecialty groups actually lose

Three attribution failures we see, and the fix

Failure 01

Incident-to billed in a facility

A hospital-based cardiology arm bills NPP visits incident-to at the physician rate. Incident-to does not exist in facility settings, so the higher payment is unsupported on audit.

Fix: facility POS routes to split/shared with modifier FS, or to the NPP's own NPI.

Failure 02

Time counted twice

A multispecialty inpatient group adds each clinician's full time and calls the physician ">50%." Overlapping minutes get double-counted, inflating who owns the visit.

Fix: count the date's total time once, then measure each clinician's share against it.

Failure 03

Attestation without performance

The physician signs an NPP's note and bills the visit, but never performed the MDM or the majority of time. The signature is not the substantive portion.

Fix: attribute to the clinician who genuinely did the time or the MDM, and document it.

Multispecialty group billing services, built for 2026 attribution

ASP-RCM Solutions runs the setting-first logic above as a standing control across your group: correct NPI, modifier FS where it belongs, incident-to gates enforced at the office, and the whole thing reconciled against the clinician your MVP measures actually follow. Fewer takebacks, cleaner quality scores, revenue credited to the person who earned it.

Get a multispecialty attribution review →

ASP-RCM Solutions · Frisco, Texas

Guidelines referenced

Calendar Year 2026 Medicare Physician Fee Schedule final rule — split/shared E/M services and the substantive-portion definition (more than half of total time, or the practitioner performing the medically necessary MDM); critical care time-only.
Medicare Benefit Policy Manual, Pub. 100-02, Chapter 15, Section 60 — Services and Supplies Furnished Incident To a physician's professional service (plan of care, direct supervision, established-patient conditions).
Modifier FS — split (or shared) evaluation and management visit, appended per CMS split/shared billing instructions.
Quality Payment Program — MIPS Value Pathways (MVPs), 2026 performance year — attribution of quality, cost, improvement activities, and promoting interoperability to the billing clinician or group.