G9999 HCPCS code: Documentation 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 precise date or details from previous colonoscopy, previous colonoscopy report was incomplete)
G9999 is the HCPCS Level II code for documentation 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 precise date or details from previous colonoscopy, previous colonoscopy report was incomplete). Its Medicare coverage code is C (Carrier judgment): Coverage is decided by the Medicare contractor (MAC) case by case.
Code details
| Field | Value |
|---|---|
| Section | G codes — Procedures and professional services (temporary) |
| Coverage code | C — Carrier judgment |
| Pricing indicator | 00 — Not separately priced by Medicare |
| BETOS category | Z2 |
| Added | 2022-01-01 |
| Last action effective | 2025-01-01 |
Medicare policy articles for this code
- A56632: Billing and Coding: Colonoscopy/Sigmoidoscopy/Proctosigmoidoscopy (Palmetto GBA (MAC - Part A, MAC - Part B))
Covered diagnoses (558 ICD-10-CM codes)
The diagnoses most often listed as covered in the policy articles above:
| ICD-10-CM | Diagnosis | Articles listing it |
|---|---|---|
| A03.9 | Shigellosis, unspecified | 1 |
| A04.3 | Enterohemorrhagic Escherichia coli infection | 1 |
| A04.5 | Campylobacter enteritis | 1 |
| A04.6 | Enteritis due to Yersinia enterocolitica | 1 |
| A04.71 | Enterocolitis due to Clostridium difficile, recurrent | 1 |
| A04.72 | Enterocolitis due to Clostridium difficile, not specified as recurrent | 1 |
| A04.8 | Other specified bacterial intestinal infections | 1 |
| A04.9 | Bacterial intestinal infection, unspecified | 1 |
| A06.1 | Chronic intestinal amebiasis | 1 |
| A06.2 | Amebic nondysenteric colitis | 1 |
Showing 10 of 558. The full list, non-covered diagnoses and CSV export are in Caduvo.
What changed for G9999
- 2022-01-01: G9999 added to HCPCS Level II
- Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01
Frequently asked questions
What is HCPCS code G9999?
G9999 is the HCPCS Level II code for documentation 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 precise date or details from previous colonoscopy, previous colonoscopy report was incomplete). Short descriptor: "Doc sys rsn <3 colon".
Does Medicare cover G9999?
Coverage code C — Carrier judgment. Coverage is decided by the Medicare contractor (MAC) case by case.
Which diagnoses support coverage for G9999?
Medicare policy articles that cite G9999 list 558 covered ICD-10-CM diagnosis codes across 1 article. The most cited include A03.9 (Shigellosis, unspecified), A04.3 (Enterohemorrhagic Escherichia coli infection), A04.5 (Campylobacter enteritis). A listed diagnosis is necessary but not sufficient; the policy's other criteria still apply.
Related G99 codes
- G9900 — Screening, diagnostic, film, digital or digital breast tomosynthesis (3d) mammography results were not documented and reviewed, reason not otherwise specified
- G9901 — Patient age 66 or older in institutional special needs plans (snp) or residing in long-term care with pos code 32, 33, 34, 54, or 56 for more than 90 consecutive days during the measurement period
- G9902 — Patient screened for tobacco use and identified as a tobacco user
- G9903 — Patient screened for tobacco use and identified as a tobacco non-user
- G9904 — Documentation of medical reason(s) for not screening for tobacco use (e.g., limited life expectancy, other medical reason)
- G9905 — Patient not screened for tobacco use
- G9906 — Patient identified as a tobacco user received tobacco cessation intervention during the measurement period or in the six months prior to the measurement period (counseling and/or pharmacotherapy)
- G9907 — Documentation of medical reason(s) for not providing tobacco cessation intervention on the date of the encounter or within the previous 12 months (e.g., limited life expectancy, other medical reason)
- G9908 — Patient identified as tobacco user did not receive tobacco cessation intervention during the measurement period or in the six months prior to the measurement period (counseling and/or pharmacotherapy)
- G9909 — Documentation of medical reason(s) for not providing tobacco cessation intervention on the date of the encounter or within the previous 12 months if identified as a tobacco user (e.g., limited life expectancy, other medical reason)
- G9910 — Patients age 66 or older in institutional special needs plans (snp) or residing in long-term care with pos code 32, 33, 34, 54 or 56 for more than 90 consecutive days during the measurement period
- G9911 — Clinically node negative (t1n0m0 or t2n0m0) invasive breast cancer before or after neoadjuvant systemic therapy
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Next steps
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Sources: CMS HCPCS Level II release October 2025; CMS DMEPOS fee schedule; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.