G9831 HCPCS Level II code: Ajcc stage at breast cancer diagnosis = ii or iii
G9831 is the HCPCS code for “Ajcc stage at breast cancer diagnosis = ii or iii” in CMS’s October 2026 release, in effect from Oct 1, 2026.
Official description
G9831Ajcc stage at breast cancer diagnosis = ii or iii
Short description: Ajcc stg brt ca dx ii or iii
HCPCS · United States
Medicare details
The indicators CMS publishes with G9831 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, 2017
Where G9831 sits
- 1G codesProcedures and professional services
- 2Active code G9831Ajcc stage at breast cancer diagnosis = ii or iii
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 G9831 mean?
G9831 is the HCPCS code for “Ajcc stage at breast cancer diagnosis = ii or iii” in CMS’s HCPCS Level II October 2026 release.
Does Medicare cover G9831?
CMS lists G9831’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 G9831
All G codesG9825Her-2/neu negative or undocumented/unknownG9826Patient transferred to practice after initiation of chemotherapyG9827Her2-targeted therapies not administered during the initial course of treatmentG9828Her2-targeted therapies administered during the initial course of treatmentG9829Breast adjuvant chemotherapy administeredG9830Her-2/neu positiveG9832Ajcc stage at breast cancer diagnosis = i (ia or ib) and t-stage at breast cancer diagnosis = t1cG9833Patient transfer to practice after initiation of chemotherapyG9834Patient has metastatic disease at diagnosisG9835Trastuzumab administered within 12 months of diagnosisG9836Reason for not administering trastuzumab documented (e.g. patient declined, patient died, patient transferred, contraindication or other clinical exclusion, neoadjuvant…G9837Trastuzumab not administered within 12 months of diagnosis