GZ HCPCS Level II modifier: Item or service expected to be denied as not reasonable and necessary

GZ is a HCPCS Level II modifier: “Item or service expected to be denied as not reasonable and necessary.” It adds this detail to the code it is reported with.

Official description

GZ

Item or service expected to be denied as not reasonable and necessary

Short description: Not reasonable and necessary

HCPCS · United States

Medicare details

The indicators CMS publishes with GZ in its October 2026 file. They describe Medicare’s handling, not another payer’s.

Medicare coverage: Non-covered by Medicare
Added: Jan 1, 2002

Where GZ sits

1GroupHCPCS modifiers
2Modifier GZItem or service expected to be denied as not reasonable and necessary

Source and release

Data release: HCPCS Level II · October 2026
Effective date: Oct 1, 2026
Publisher: CMS

This page is built from the HCPCS Level II catalog that Vero Codes reads when it suggests codes: Centers for Medicare & Medicaid Services’s October 2026 release, imported from the publisher’s file and checked against it. The description, notes and structured data come from the same record.

See GZ in the CMS source

Frequently asked questions

What does HCPCS code GZ mean?

GZ is the HCPCS code for “Item or service expected to be denied as not reasonable and necessary” in CMS’s HCPCS Level II October 2026 release.

Where is GZ in the HCPCS Level II list?

GZ is listed under Modifiers.

Does Medicare cover GZ?

CMS lists GZ’s Medicare coverage as “Non-covered by Medicare”. Coverage and payment still depend on the patient, the setting, the documentation and the payer.

Which HCPCS Level II release does this page use?

It uses CMS’s October 2026 release, in effect from Oct 1, 2026 to Dec 31, 2026. It is a reference: confirm the code against the current list and the payer’s rules before you submit it.

All modifiers

GTVia interactive audio and video telecommunication systems GUWaiver of liability statement issued as required by payer policy, routine notice GVAttending physician not employed or paid under arrangement by the patient's hospice provider GWService not related to the hospice patient's terminal condition GXNotice of liability issued, voluntary under payer policy GYItem or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit H9Court-ordered HAChild/adolescent program HBAdult program, non geriatric HCAdult program, geriatric HDPregnant/parenting women's program HEMental health program