Crystal's Coder Hub📹 Modifier -GT — Via Interactive Audio and Video Telecommunications Systems
Quick Reference
Modifier: -GT | Type: HCPCS Level II Modifier | Used With: CPT / HCPCS Service Codes | Telehealth Type: Synchronous (Real-Time Interactive Audio + Video) | Real-Time Interaction Required: ✅ Yes | Medicare Professional Claims: ⚠️ Retired — Use POS 02/10 Instead | Medicare Institutional (CAH Method II): ✅ Still Required
📋 Modifier Description
Modifier -GT — “Via interactive audio and video telecommunications systems” — is a HCPCS Level II modifier that identifies a service delivered through real-time, two-way, interactive audio and video telecommunications. Unlike Modifier -GQ (asynchronous store-and-forward), -GT requires a live, simultaneous encounter between the patient at the originating site and the provider at the distant site — both parties are present and communicating in real time.
Modifier -GT has a significant history** in Medicare telehealth billing but has been substantially retired from professional claim use. Effective January 1, 2018, CMS eliminated the requirement to use Modifier -GT on professional claims (CMS-1500 / 837P) for Medicare patients. In its place, CMS instructs that appending the appropriate Place of Service code — POS 02 or POS 10 — is sufficient to certify that the telehealth requirements have been met. -GT was also effectively superseded on the professional side by Modifier -95, which the AMA introduced in 2017 as the standardized synchronous telehealth modifier for non-Medicare payers.
⚠️ Medicare Professional Claims — -GT Is Retired
Do NOT append Modifier -GT to Medicare professional (CMS-1500 / 837P) claims for standard physician/practitioner telehealth services. CMS no longer requires it, and submitting -GT on professional claims where only POS 02/10 is needed will not cause a denial but reflects outdated billing practice. The one active Medicare exception is Critical Access Hospital (CAH) Method II institutional claims, where -GT remains required on the distant-site professional service line billed on the UB-04. Outside of that context, -GT on a Medicare professional claim is vestigial at best — and a red flag to reviewers at worst.
🔬 Modifier -GT vs. Other Telehealth Modifiers
| Modifier | Full Name | Interaction Type | Medicare Professional Use (2025–2026) | Medicare Institutional Use |
|---|---|---|---|---|
| -GT | Via Interactive Audio and Video Telecommunications Systems | Synchronous (Live Audio + Video) | ⚠️ Retired — POS 02/10 replaces it | ✅ Required for CAH Method II |
| -95 | Synchronous Telemedicine Service Rendered Via Real-Time Interactive Audio and Video | Synchronous (Live Audio + Video) | ⚠️ AMA standard modifier; not recognized by Medicare for professional claims | ❌ Not used on institutional |
| -93 | Synchronous Telemedicine Service Rendered Via Telephone or Other Real-Time Interactive Audio-Only Telecommunications System | Synchronous (Audio-Only) | ✅ Medicare audio-only professional claims | ❌ Not applicable |
| -GQ | Via an Asynchronous Telecommunications System | Asynchronous (Store-and-Forward) | ⚠️ Limited — AK/HI Federal Demo Projects only | ❌ Not standard |
| -FQ | Service Furnished Using Audio-Only Communication Technology | Synchronous (Audio-Only) | ✅ FQHC/RHC audio-only visits | ❌ Not standard |
Clinical Pearl
The most common -GT confusion in 2025–2026 is coding staff continuing to append -GT to Medicare professional claims out of habit — this was correct pre-2018, but CMS retired it for professional billing. The current correct workflow for a standard Medicare synchronous telehealth visit is: correct CPT code + POS 02 or POS 10 — no telehealth modifier needed on the CMS-1500. -GT is alive and required only on the professional service line of a CAH Method II UB-04 institutional claim. Know your claim type before choosing your modifier.
✅ When to Use Modifier GT
- CAH Method II — Institutional Billing (UB-04): The Critical Access Hospital is billing for distant-site physician/practitioner telehealth services under CAH Method II; -GT is appended to the professional service line on the institutional claim
- Commercial Payers That Still Recognize -GT: Some commercial payer contracts predate the widespread adoption of Modifier -95 and still require or accept -GT for synchronous telehealth — always verify the current payer-specific telehealth modifier policy
- Some Medicaid Programs: State Medicaid programs vary widely; some still require -GT for synchronous telehealth professional claims — confirm the state-specific billing companion guide before submitting
❌ When NOT to Use Modifier GT
| Scenario | Correct Approach |
|---|---|
| Medicare professional (CMS-1500) — standard physician/practitioner synchronous telehealth | POS 02 or POS 10 — no modifier needed |
| Non-Medicare commercial synchronous audio/video telehealth | -95 (verify payer policy) |
| Medicare audio-only telehealth (professional) | -93 |
| Asynchronous store-and-forward | -GQ |
| FQHC/RHC audio-only services | -FQ |
| In-person service | No telehealth modifier — use appropriate POS (e.g., POS 11) |
Denial / Compliance Alert
Appending -GT to a Medicare professional claim that only requires POS 02/10 is not technically a denial trigger, but it is an outdated practice that can flag a claim for review. More critically — **never substitute -GT for POS 02/10 on a professional claim while leaving the POS as 11 (Office). The POS is what certifies telehealth for Medicare, not the modifier. If POS 11 is used with -GT on a Medicare professional claim, the telehealth nature of the service is not properly certified, creating a compliance risk and potential overpayment.
🏷️ Modifier Placement & Claim Submission
| Field | Guidance |
|---|---|
| Where Appended | Appended to the CPT or HCPCS service code on the professional service line (e.g., 99213-GT on a CAH Method II UB-04) |
| Claim Type — Medicare | Institutional (UB-04 / 837I) — CAH Method II ONLY; not for CMS-1500 / 837P professional claims |
| Claim Type — Non-Medicare | Professional (CMS-1500 / 837P) when payer still requires -GT — verify payer policy |
| Place of Service | POS 02 (telehealth outside patient’s home) or POS 10 (telehealth in patient’s home) |
| Billing Provider | Distant-site provider — the physician or practitioner conducting the real-time encounter |
| Originating Site | Location where the patient is present during the live encounter |
| Documentation Required | Confirm real-time audio + video interaction; document patient location (originating site); provider location (distant site); nature of encounter; clinical findings and plan |
📝 Coding Examples
Example 1 — CAH Method II Institutional Claim: Synchronous Telehealth E/M
Clinical Scenario: A Medicare patient is located at a rural Critical Access Hospital in Montana (originating site). A physician at a distant academic medical center conducts a synchronous, real-time audio-video telehealth visit to evaluate the patient for a new complaint of chest discomfort. The CAH is billing under Method II and submitting an institutional UB-04 claim that includes the distant-site professional service line. The encounter meets all documentation requirements for a level 3 established patient office visit.
| Field | Code | Rationale |
|---|---|---|
| CPT + Modifier | 99213-GT | Established patient office visit, low-medical-decision-complexity — -GT required on institutional claim for CAH Method II distant-site professional service line |
| Claim Type | UB-04 (837I) | CAH Method II institutional billing — -GT is still required in this context per CMS guidance |
| POS | 02 | Telehealth provided other than in patient’s home |
| PDx | R07.9 | Chest pain, unspecified — primary reason for encounter |
Note
On a CAH Method II UB-04, the distant-site physician’s professional service is billed on the institutional claim itself — not on a separate CMS-1500. -GT is appended to the CPT service line within that institutional claim. This is the only current Medicare context where -GT is required. If this same encounter were billed by a non-CAH physician on a CMS-1500, no modifier would be needed — only POS 02.
Example 2 — Commercial Payer: Synchronous Telehealth Visit, GT Required by Contract
Clinical Scenario: A 44-year-old established patient has a follow-up visit for hypertension management via real-time audio-video telehealth. The commercial payer (non-Medicare) contract for this practice still specifies Modifier GT for synchronous telehealth services and does not yet recognize Modifier 95. The provider conducts a level 3 established patient visit with documented medication review and blood pressure trending. The patient is at home during the visit.
| Field | Code | Rationale |
|---|---|---|
| CPT + Modifier | 99213-GT | Established patient E/M, low complexity — GT appended per commercial payer contract requirement for synchronous telehealth |
| Claim Type | CMS-1500 (837P) | Professional claim — commercial payer, not Medicare |
| POS | 10 | Telehealth provided in patient’s home |
| PDx | I10 | Essential (primary) hypertension — primary reason for visit |
Warning
Do not assume this billing pattern is correct for Medicare. The GT modifier on a CMS-1500 is a commercial/Medicaid payer-specific practice in 2025–2026. For Medicare, POS 02 or POS 10 is sufficient — no modifier is needed on the professional claim. Mixing up these workflows across payers is one of the most common audit triggers in telehealth billing.
⚠️ Common Coding Pitfalls
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**Appending -GT to Medicare Professional Claims (CMS-1500): This was correct pre-2018 but CMS retired -GT for professional claims effective January 1, 2018. The correct Medicare professional telehealth certification is POS 02 or POS 10 alone — no modifier required. Continuing to use -GT on CMS-1500 Medicare claims reflects outdated workflow and can flag a claim for review.
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Confusing -GT with Modifier -95: -GT and Modifier -95 both describe synchronous audio-video telehealth, but they are NOT interchangeable for Medicare. Medicare does not recognize Modifier -95 for professional claims — it uses POS 02/10 instead. Modifier -95 is the AMA standard used by most commercial payers. Appending -95 to a Medicare professional claim will not cause a denial but is technically incorrect per CMS guidance.
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Using -GT on the Wrong Claim Type for CAH: -GT is required for CAH Method II on institutional claims (UB-04). If a CAH physician separately bills a CMS-1500 under Method I, -GT rules differ — confirm the CAH billing method before selecting the modifier. Applying -GT on a Method I CMS-1500 when Method II UB-04 is the correct vehicle creates a duplicate billing risk.
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Wrong POS with GT: Submitting -GT with POS 11 (Office) on a professional claim while intending to bill a telehealth encounter is a compliance failure. The POS must reflect the nature of the encounter — POS 02 or POS 10 for telehealth. This mismatch signals a potentially fraudulent claim: you are certifying both an in-person encounter (POS 11) and a telehealth delivery (-GT) simultaneously.
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Assuming Commercial Payers Still Require GT: Many commercial payers have migrated to requiring Modifier -95 for synchronous telehealth. Submitting -GT when the payer has updated to -95 may result in a denial or a request for documentation. Always pull the current payer telehealth billing companion guide — ideally at the start of each calendar year when policy updates typically roll out.
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Failing to Document Real-Time Audio + Video: -GT certifies a live, simultaneous, two-way audio-video encounter. If the video component failed and the visit was completed via audio only, -GT is incorrect — the appropriate modifier shifts to Modifier -93. The medical record must document that real-time audio and video were used for the duration of the clinically relevant portion of the visit.
📎 Sources
1 AMA CPT 2025 Professional Edition — Appendix P (Telehealth Services) and Modifier definitions 2 CMS Transmittal R3929CP (Pub 100-04) — Elimination of GT Modifier Requirement for Professional Claims, effective January 1, 2018 3 CMS Telehealth FAQ, Updated February 2026 (CMS.gov) 4 CMS Medicare Physician Fee Schedule Final Rule 2025 (CMS-1807-F) 5 AAPC Knowledge Center — “Modifier GT Eliminated for Telehealth Services” (February 2023) 6 WPS Government Health Administrators — “Overview of Medicare Telehealth Policy: Past, Present, and Future” (September 2025) 7 Novitas Solutions Medicare JH — Telehealth Service Modifiers Policy (February 2026) 8 Mend — “2026 Telemedicine Billing: GT, 95 & GQ Modifier Differences” (January 2026) 9 ICD-10-CM Official Guidelines for Coding and Reporting FY2025 10 CombineHealth — “Modifier 95 in Telehealth Billing: Complete 2026 Guide” (May 2026)