HCC 329: Chronic Kidney Disease, Moderate (Stage 3, Except 3B) ICD-10-CM
CMS-HCC Category 329 (Chronic Kidney Disease, Moderate (Stage 3, Except 3B)) is a payment HCC in the V28 Medicare Advantage risk adjustment model. For payment year 2026 it adds a risk adjustment factor between 0.116 and 0.181 to a beneficiary's RAF score depending on the payment segment (0.127 for a community, non-dual, aged enrollee). 2 ICD-10-CM diagnosis codes map to HCC 329. A more severe related category (HCC 326, HCC 327, and HCC 328) supersedes it when both are reported.
RAF Weight by Payment Segment 7 segments
| Payment Segment | Relative Factor |
|---|---|
| Community, non-dual, aged | 0.127 |
| Community, partial-benefit dual, aged | 0.140 |
| Community, full-benefit dual, aged | 0.116 |
| Community, non-dual, disabled | 0.179 |
| Community, partial-benefit dual, disabled | 0.178 |
| Community, full-benefit dual, disabled | 0.181 |
| Institutional | 0.145 |
A beneficiary is scored in exactly one segment, set by Medicaid (dual) status, aged or disabled entitlement, and residence. Factors are relative weights, not dollar amounts; new-enrollee segments score on demographics only. In the hierarchy, HCC 326 (Chronic Kidney Disease, Stage 5), HCC 327 (Chronic Kidney Disease, Severe (Stage 4)), and HCC 328 (Chronic Kidney Disease, Moderate (Stage 3B)) supersede HCC 329 when reported together.
ICD-10-CM Codes That Map to HCC 329 2 codes
- N18.30 Chronic kidney disease, stage 3 unspecified from V24 HCC 138
- N18.31 Chronic kidney disease, stage 3a from V24 HCC 138
Every code above carries the full HCC 329 weight when documented and reported on a Medicare Advantage encounter. The code link opens its full page with the complete risk adjustment card.
Questions About HCC 329
What is HCC 329 in the CMS-HCC model?
HCC 329 is CMS-HCC Category 329 (Chronic Kidney Disease, Moderate (Stage 3, Except 3B)) in the V28 risk adjustment model. It covers 2 ICD-10-CM diagnosis codes that raise a Medicare Advantage beneficiary's risk score when documented.
What is the RAF weight for HCC 329?
For payment year 2026, HCC 329 adds 0.127 to the RAF score of a community, non-dual, aged beneficiary. The published weights range from 0.116 to 0.181 across the seven payment segments shown above.
Which categories supersede HCC 329?
HCC 326 (Chronic Kidney Disease, Stage 5), HCC 327 (Chronic Kidney Disease, Severe (Stage 4)), and HCC 328 (Chronic Kidney Disease, Moderate (Stage 3B)) sit above HCC 329 in the hierarchy: when a beneficiary has diagnoses in both, only the more severe category is paid.
Related References
Source: Centers for Medicare & Medicaid Services, Payment Year 2026 risk adjustment mapping and model software releases (CMS-HCC V28), applied to the FY 2026 ICD-10-CM code set. ICD List is not affiliated with CMS.
