Overview
Modifier GT carries the CMS descriptor "via interactive audio and video telecommunication systems" and has been in the HCPCS file since January 1, 1999. For most of Medicare's telehealth history it was how a distant-site practitioner told the contractor that a covered service had been delivered remotely. That changed in two steps. CMS created place of service code 02 for telehealth effective January 1, 2017, and a 2017 change request eliminated GT from professional claims from January 2018, leaving the place of service code to identify telehealth on the CMS-1500 and the 837P.
The current rule for professional claims sits in chapter 26, section 10.5 of the Medicare Claims Processing Manual: a telehealth service is billed with place of service 02 or 10, depending on whether the patient is at home, and paired with CPT modifier 95 for audio and video or 93 for audio only. During the COVID-19 public health emergency CMS temporarily asked practitioners to report the place of service that would have applied in person with modifier 95, which is why claims from 2020 to 2023 look different from both the older GT claims and today's.
GT survives on institutional claims. Chapter 12, section 190.6.1 tells a critical access hospital that has elected method II, and to which the practitioner has reassigned benefits, to bill the distant-site telehealth service with GT on its own claim; the MAC then pays 80 percent of the physician fee schedule amount for the distant-site service. Its sibling GQ, "via asynchronous telecommunications system", covers store-and-forward telehealth in the federal demonstrations in Alaska and Hawaii, under section 190.6.2.
Outside Medicare fee-for-service the picture varies. Some Medicaid programs and commercial plans still ask for GT, some accept 95, and some want both a modifier and a telehealth place of service code. Because the modifier and the place of service code now carry different meanings for Medicare, payer-specific billing rules belong in the charge master or claim scrubber rather than in a single default, and a GT that is right for one payer can be the reason another returns the claim.
Coding teams also meet GT when they work older claims and appeals. A Medicare professional telehealth claim from before 2017 carries GT without a telehealth place of service, one from 2017 both GT and POS 02, one from 2018 or 2019 POS 02 alone, one from the public health emergency the in-person place of service with modifier 95, and a current one POS 02 or 10 with 95 or 93. Matching the modifier to the date of service, rather than to today's rule, avoids correcting a claim that was right when it was billed.
Worked example
A psychiatrist reassigns benefits to a rural critical access hospital that has elected method II and furnishes a psychotherapy visit by video to a patient at a distant clinic. The hospital bills the service on its institutional claim with modifier GT, and the MAC pays 80 percent of the fee schedule amount for the distant-site service. A psychiatrist in private practice furnishing the same video visit bills it on a professional claim with place of service 02 or 10 and modifier 95, and no GT.
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Frequently asked questions — Modifier GT (Interactive Audio and Video Telecommunication)
Is the GT modifier still valid?
Yes, it is active in the HCPCS file. Medicare no longer uses it on professional claims, where place of service 02 or 10 with modifier 95 or 93 identifies telehealth, but critical access hospitals billing distant-site services under method II still report GT.
What replaced GT on Medicare professional claims?
Place of service code 02 from January 2018, joined by POS 10 for patients at home from 2022. Since 2024 the place of service is paired with modifier 95 for audio and video or 93 for audio only, and the place of service decides the payment rate.
What is the difference between GT and modifier 95?
GT is a HCPCS Level II modifier maintained by CMS; 95 is a CPT modifier. Both indicate real-time audio and video. Medicare pairs 95 with a telehealth place of service on professional claims and keeps GT for CAH method II claims; other payers choose either, so check the plan's telehealth policy.
Disclaimer
This glossary entry is operational reference for revenue-cycle and medical-billing professionals. It is not legal, clinical, or contractual advice. Industry benchmarks cite named public sources where available; always verify against the current guidance from the authority body before relying on a number in a contract, policy, or compliance filing.