Modifier 26 and TC: Splitting a Diagnostic Service Correctly

Modifier 26 and modifier TC are usually taught as two modifiers. They are better understood as one decision with three possible answers: global, professional component only, or technical component only. Getting it right is not a coding preference — it determines who is entitled to bill, in which place of service, and whether a claim will be recouped months later when the hospital’s own claim reaches the Common Working File.

This guide is aimed at the moment when a diagnostic service has been furnished and someone has to decide which of the three ways to report it. The split is the whole concept, so the two modifiers are covered together.

What the Two Components Actually Are

The professional component (PC, modifier 26) is the physician’s interpretive work: reviewing the study and producing a written report. The Claims Processing Manual (Publication 100-04, Chapter 13, Section 20.1) is specific that the interpretation of a diagnostic procedure includes a written report. Relative value units for a service reported with modifier 26 include physician work, practice expense and malpractice expense.

The technical component (TC) is everything that produced the study: equipment, supplies, technologist time, facility overhead. RVUs for a service reported with TC include practice expense and malpractice expense only — no physician work.

The global service is both, reported with no modifier, and its RVUs equal the sum of the two components. That last point is the useful sanity check: if one entity performed both the technical work and the interpretation and is billing for both, no modifier belongs on the claim at all.

The Decision Rule: Read the PC/TC Indicator First

The Physician Fee Schedule assigns every code a professional component / technical component indicator, and that indicator — not clinical reasoning — decides whether modifiers 26 and TC are even permitted. The full set, as described in the Claims Processing Manual’s fee schedule policy indicator file layout (Chapter 23, Section 50.6):

• 0 — Physician service codes. Visits, consultations, surgical procedures. The PC/TC concept does not apply and modifiers 26 and TC cannot be used.
• 1 — Diagnostic tests or radiology services. These generally have both components and 26 and TC can be used. This is the indicator that makes the whole question live.
• 2 — Professional component only codes. Stand-alone codes describing the physician work portion, where separate codes exist for the technical component and for the global test. The manual’s example is 93010 (electrocardiogram; interpretation and report). 26 and TC cannot be used — the code already is the professional component.
• 3 — Technical component only codes. Stand-alone technical codes, example 93005 (electrocardiogram, tracing only, without interpretation and report), plus codes covered only as diagnostic tests with no related professional code. 26 and TC cannot be used.
• 4 — Global test only codes. Stand-alone global codes where separate PC-only and TC-only codes exist. 26 and TC cannot be used.
• 5 — Incident-to codes. Services covered incident to a physician’s service when furnished by auxiliary personnel under direct supervision. Not payable to carriers for hospital inpatients or hospital outpatient department patients. 26 and TC cannot be used.
• 6 — Laboratory physician interpretation codes. Clinical laboratory codes for which separate payment for a laboratory physician’s interpretation may be made; performance of the test itself is paid under the clinical laboratory fee schedule. Modifier TC cannot be used with these codes.
• 7 — Physical therapy service. Payment may not be made where furnished to a hospital inpatient or outpatient by an independently practising physical or occupational therapist.
• 8 — Physician interpretation codes. The professional component of clinical laboratory codes payable only where the physician interprets an abnormal smear for a hospital inpatient — the manual notes this applies only to code 85060, and no TC billing is recognised.
• 9 — The professional/technical component concept does not apply.

So the first question is never “should I use 26 or TC?” It is “what is this code’s PC/TC indicator?” For anything other than indicator 1 (and indicator 6 for modifier 26 on lab interpretations), the answer is that neither modifier belongs.

The Second Question: Who Furnished Which Component, and Where

Once the code permits a split, the decision is factual.

• One entity performed the study and interpreted it, in its own enrolled location. Bill globally, no modifier.
• A physician interpreted a study performed elsewhere. The physician bills with modifier 26; the entity that owns the equipment bills TC.
• The two components were furnished in different enrolled practice locations. Contractor guidance is that they must then be billed separately rather than globally, even within the same organisation.

The place-of-service rule that generates most recoupments

For hospital patients, the technical component is not separately payable to a physician or supplier. Chapter 13 states that A/B MACs (B) may not pay the TC of radiology services furnished to hospital patients; that payment for the provider services needed to produce the radiology service is made to the hospital; and that for hospital inpatients other than critical access hospitals the TC is included in the prospective payment to the hospital. Hospital bundling rules exclude payment to suppliers for the TC for beneficiaries in an inpatient stay.

The enforcement mechanism is worth knowing because it is retrospective. When a hospital inpatient claim reaches the Common Working File, the CWF compares the admission and discharge dates against the line-item service date on any supplier-billed TC line. Where the service date falls inside the stay, it generates an unsolicited response, and the A/B MAC adjusts the TC line and recoups the payment. A TC claim that paid cleanly is not evidence that it was payable.

Anatomic pathology has an analogous restriction: contractor guidance states that an independent laboratory may not bill the TC of a physician pathology service furnished to a hospital inpatient or outpatient.

A note on contrast

Contrast agents supplied in single-dose containers fall under a separate but adjacent rule set: the Claims Processing Manual names contrast agents explicitly among the drugs to which the discarded-drug modifier policy applies. So an imaging service can generate both a component decision on the study and a wastage attestation on the contrast — see modifiers JW and JZ.

Purchased components and the anti-markup limitation

A physician or supplier may bill and receive Part B payment for the TC or PC of a diagnostic test they contracted another physician, group or supplier to perform. But where the performing physician does not “share a practice” with the ordering and billing entity, the anti-markup payment limitation applies — the payable amount becomes the lowest of the performing supplier’s net charge to the biller, the biller’s actual charge, or the fee schedule amount for the jurisdiction where the service was performed. The limitation has applied to the TC of certain diagnostic tests since 1994 and to the PC of diagnostic tests (other than clinical diagnostic laboratory tests) since 1 January 2009.

The documentation consequence is concrete: the billing entity must identify the performing physician or supplier, including their NPI, and the net amount charged to the biller. Chapter 13 states that if the physician does not identify who performed the test and supply the required information, no payment is allowed, and the physician may not bill the beneficiary any amount. Clinical diagnostic laboratory tests sit outside this claim-and-payment procedure.

Where This Meets the Laboratory

The PC/TC split is where imaging billing and laboratory billing diverge sharply, and the divergence is the single most useful thing to understand if you work across both.

Clinical laboratory tests paid under the clinical laboratory fee schedule generally have no professional component to split. That is what PC/TC indicators 6 and 8 encode: the test itself is paid under the lab fee schedule, and only a narrow set of laboratory physician interpretations is separately payable — with TC unavailable on those codes because the technical work is already paid elsewhere. If a claim proposes to split a routine chemistry or haematology test into 26 and TC lines, the premise is wrong before the arithmetic starts. A repeat of such a test on the same day is a modifier 91 question, not a component question.

Anatomic pathology and molecular pathology are different. Here the split is real and routine, and the NCCI Policy Manual’s pathology chapter works through it directly. For in situ hybridization services, where a physician (M.D. or D.O.) reads, quantitates and interprets the probe-stained tissue, the provider may report the global code or the professional component with modifier 26 as appropriate, and the laboratory may report the technical component with TC. Where a laboratory scientist or technician performs that reading and quantitation instead, the manual directs that the laboratory not report the technical component of those codes and that a different code range be used instead. The person who did the work determines the code, not the department that owns the instrument.

Operationally, this is a systems problem as much as a coding one. Whether the professional component can be billed at all depends on whether the interpreting physician’s report exists as a discrete, attributable, retrievable document — which is a question about the radiology information system, the PACS archive and the reporting workflow, or about the laboratory information system and the digital pathology pipeline. Sites that split components across entities and cannot produce the signed interpretive report on request have a documentation failure that no modifier fixes.

What the Record Must Show

• For a professional component claim: a written interpretive report. Not a note referencing the result, not a value transcribed into a progress note — an interpretation with a report, attributable to the billing physician. This is the requirement most often assumed rather than verified.
• For a technical component claim: evidence the billing entity owned or bore the cost of the equipment, supplies and staff, and that the place of service permits separate TC payment. If the patient was a hospital inpatient, that evidence will not help.
• For a global claim: both of the above, in the same entity, in the same enrolled location.
• For a purchased component: the performing supplier’s identity and NPI and the net charge, without which no payment is allowed at all.

The Misuse That Triggers Denials and Recoupment

1. Appending 26 or TC to a code whose PC/TC indicator forbids it. Indicators 0, 2, 3, 4 and 5 all prohibit both modifiers; indicator 6 prohibits TC. Where a stand-alone professional-component code already exists (the 93010 pattern), appending modifier 26 to the global code instead of reporting the PC-only code is a distinct and common error.
2. Billing TC for a hospital inpatient or outpatient. Payable at submission, recouped after the hospital claim posts.
3. Billing globally when the components were furnished by different entities or in different enrolled locations. This is the pattern that produces duplicate-payment exposure, because the other entity is usually billing its component too.
4. Appending modifier 26 where the practice performed the whole service. The global code without a modifier is the correct report; adding 26 simply forfeits the technical payment.
5. Treating the anti-markup limitation as optional. The information requirement is a payment condition, not a documentation nicety.

Modifier 26/TC vs. Its Nearest-Confused Siblings

26/TC vs. modifier 90

Modifier 90 (reference or outside laboratory) answers who performed the test when the billing entity did not. Modifiers 26 and TC answer which part of a splittable service is being billed. A referring physician billing for a test an outside lab ran is a modifier 90 situation; a radiologist reading a hospital’s film is a modifier 26 situation. Confusing them typically produces a claim from an entity that is not entitled to bill at all.

26/TC vs. modifier 91

Modifier 91 answers how many times, on clinical laboratory tests specifically. It has no component dimension, and clinical lab fee schedule tests generally have no component split, so the two questions rarely both apply.

26/TC vs. modifier 76

Modifier 76 flags a repeat of the same procedure by the same physician on the same day — commonly used on repeat imaging. It coexists comfortably with 26 or TC on the same line, because it answers a different question, but it does not substitute for either.

26/TC vs. modifier 51

Where several diagnostic imaging studies are performed in one session, a Multiple Procedure Payment Reduction may reduce the technical or professional component of the later ones — which is a modifier 51 family question operating on top of, not instead of, the component split.

Where Jurisdiction Matters

The PC/TC indicator assignments and the hospital-bundling rules are national. What varies is contractor operational guidance: how a MAC expects components billed when a practice has multiple enrolled locations, how it handles specific place-of-service codes, what it looks for in an anti-markup disclosure, and what its local policies say about pathology TC billing. Noridian, Novitas and First Coast all publish modifier 26 pages with differing emphasis. Commercial payers frequently follow the CPT convention and the fee schedule indicators but set their own place-of-service edits. Verify against the payer actually adjudicating the claim.

Frequently Asked Questions

How do I know whether a code can be split into 26 and TC?

Look up its PC/TC indicator in the current Physician Fee Schedule file. Indicator 1 means both modifiers are available. Indicators 0, 2, 3, 4, 5 and 9 mean neither is. Indicator 6 permits modifier 26 but not TC. This is a lookup, not a judgement call.

Can a hospital-based radiologist bill globally?

Generally no for hospital patients. The technical component of radiology services furnished to hospital patients is paid to the hospital, not separately to the physician or supplier, so the physician’s claim is the professional component with modifier 26. Billing globally in that setting invites a recoupment driven by the Common Working File comparison against the hospital’s own claim.

Is there a professional component on a routine blood test?

Generally not. Clinical laboratory tests paid under the clinical laboratory fee schedule are paid for the test itself; only a narrow set of laboratory physician interpretation codes (PC/TC indicators 6 and 8) supports separate payment for a physician’s interpretation, and TC is unavailable on those. Anatomic and molecular pathology behave differently and do split.

Do modifiers 26 and TC affect the CLIA requirements for a test?

No. Component billing is a payment question; CLIA certification governs who may perform the testing at all. A laboratory’s certificate level and quality-control obligations are unchanged by how the resulting claim is split — see CASRAI’s guides on CLIA certification and CLIA quality control requirements.

What happens if both the interpreting physician and the facility bill globally?

One of the two claims is wrong, and the duplicate exposure is real. The routine fix is to establish a single, documented rule about which entity bills which component for each service line and each place of service, rather than resolving it claim by claim after denials appear.

Related CASRAI Resources

• PACS: picture archiving and communication systems — where the interpretive report the professional component depends on actually lives
• Radiology information system (RIS)
• DICOM conformance statement
• Digital pathology scanners
• Modifier 91: repeat clinical diagnostic laboratory test
• Modifier 76: repeat procedure by the same physician
• Modifier 51 vs modifier 59
• Modifier 59 and the X{EPSU} subset modifiers
• CLIA certification and high-complexity testing requirements
• Modifiers JW and JZ: drug wastage — the contrast-agent counterpart on an imaging claim
• Modifier GA: waiver of liability and the ABN — where a diagnostic test is expected to be denied
• The Anti-Kickback Statute in healthcare — relevant background to arrangements where components are purchased between entities

Sources: CMS Medicare Claims Processing Manual, Publication 100-04, Chapter 13, Sections 20.1–20.3.2 and 90; Chapter 23, Section 50.6 (Physician Fee Schedule payment policy indicator file record layout); Chapter 12, Section 20.2; CMS National Correct Coding Initiative Policy Manual, Chapter 10 (pathology and laboratory services), revision date 1/1/2026; Noridian Healthcare Solutions modifier 26 guidance. CPT is a registered trademark of the American Medical Association; descriptors are summarised, not reproduced. General reference material only — verify against the current fee schedule file and your payer’s policy.