G9998 HCPCS Level II code: Documentation of medical reason(s) for an interval of less than 3 years since the last colonoscopy (e.g., last colonoscopy incomplete, last colonoscopy had…
G9998 is the HCPCS code for “Documentation of medical reason(s) for an interval of less than 3 years since the last colonoscopy (e.g., last colonoscopy incomplete, last colonoscopy had inadequate prep, piecemeal removal of…” in CMS’s October 2026 release, in effect from Oct 1, 2026.
Official description
G9998Documentation of medical reason(s) for an interval of less than 3 years since the last colonoscopy (e.g., last colonoscopy incomplete, last colonoscopy had inadequate prep, piecemeal removal of adenomas, or sessile serrated polyps >= 20 mm in size, last colonoscopy found greater than 10 adenomas, lower gastrointestinal bleeding, or patient at high risk for colon cancer due to underlying medical history ([i.e. crohn's disease, ulcerative colitis, personal or family history of colon cancer, hereditary colorectal cancer syndromes])
Short description: Doc med rsn <3 colon
HCPCS · United States
Medicare details
The indicators CMS publishes with G9998 in its October 2026 file. They describe Medicare’s handling, not another payer’s.
- Medicare coverage
- Carrier judgment
- Medicare pricing
- Service not separately priced by Part B (e.g., services not covered, bundled, used by Part A only, etc.)
- Type of service
- Medical care
- BETOS category
- Undefined codes
- Added
- Jan 1, 2022
Where G9998 sits
- 1G codesProcedures and professional services
- 2Active code G9998Documentation of medical reason(s) for an interval of less than 3 years since the last colonoscopy (e.g., last colonoscopy incomplete, last colonoscopy had inadequate prep, piecemeal removal of adenomas, or sessile serrated polyps >= 20 mm in size, last colonoscopy found greater than 10 adenomas, lower gastrointestinal bleeding, or patient at high risk for colon cancer due to underlying medical history ([i.e. crohn's disease, ulcerative colitis, personal or family history of colon cancer, hereditary colorectal cancer syndromes])
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.
Frequently asked questions
What does HCPCS code G9998 mean?
G9998 is the HCPCS code for “Documentation of medical reason(s) for an interval of less than 3 years since the last colonoscopy (e.g., last colonoscopy incomplete, last colonoscopy had inadequate prep, piecemeal removal of adenomas, or sessile serrated polyps >= 20 mm in size, last colonoscopy found greater than 10 adenomas, lower gastrointestinal bleeding, or patient at high risk for colon cancer due to underlying medical history ([i.e. crohn's disease, ulcerative colitis, personal or family history of colon cancer, hereditary colorectal cancer syndromes])” in CMS’s HCPCS Level II October 2026 release.
Does Medicare cover G9998?
CMS lists G9998’s Medicare coverage as “Carrier judgment” and its pricing as “Service not separately priced by Part B (e.g., services not covered, bundled, used by Part A only, etc.)”. 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.
Codes beside G9998
All G codesG9992Palliative care services used by patient any time during the measurement periodG9993Patient was provided palliative care services any time during the measurement periodG9994Patient is using palliative care services any time during the measurement periodG9995Patients who use palliative care services any time during the measurement periodG9996Documentation stating the patient has received or is currently receiving palliative or hospice careG9997Documentation of patient pregnancy anytime during the measurement period prior to and including the current encounterG9999Documentation of system reason(s) for an interval of less than 3 years since the last colonoscopy (e.g., unable to locate previous colonoscopy report, patient cannot provide…