ICD-10 to RxHCC Mapping 2027: How It Works and Where to Get It
Every payable Part D diagnosis travels the same path: ICD-10-CM code → RxHCC category → coefficient → hierarchy → risk score. CMS publishes the official ICD-10-to-RxHCC mappings as part of the 2027 RxHCC model software on the CMS risk adjustment page — thousands of rows, distributed as data files alongside the Rate Announcement's coefficient tables.
Worked examples
| ICD-10-CM | Description | Maps to | 2027 MA-PD coefficient* |
|---|---|---|---|
| B20 | HIV disease | RXHCC1 HIV/AIDS | 8.304 |
| B18.2 | Chronic viral hepatitis C | RXHCC54 Chronic Viral Hepatitis C | 0.211 |
| E11.65 | Type 2 diabetes with hyperglycemia | RXHCC31 Diabetes without Complication | 0.232 |
| E11.22 | Type 2 diabetes with diabetic CKD | RXHCC30 Diabetes with Complications | 0.429 |
| I50.9 | Heart failure, unspecified | RXHCC186 Heart Failure | 0.163 |
| G20 | Parkinson's disease | RXHCC161 Parkinson Disease | 0.320 |
\* Community, non-low-income, age 65+, continuing enrollee segment. Full values for all 84 categories and both plan types: 2027 coefficients table and CSV download. Always validate against the official CMS mapping files before using any mapping in payment workflows.
Three mapping rules that cost plans money
- Specificity changes the category. "Diabetes, unspecified" and "diabetes with renal manifestations" land in different RxHCCs with different weights — and the hierarchy drops the lesser one. Documentation that never reaches specificity never reaches payment.
- The 2027 exclusions apply at the source. Diagnoses from audio-only visits and unlinked chart review records are excluded from 2027 payment even if the ICD-10 code maps cleanly (CY2027 Rate Announcement, Attachment VIII).
- Mappings are versioned by payment year. A code-to-category mapping valid for 2026 is not authoritative for 2027. Use the mapping files bundled with the 2027 model software.
Frequently asked questions
Is there a single official ICD-10 → RxHCC crosswalk?
Yes — CMS publishes it with the model software for each payment year on its risk-adjustment page, in text/CSV formats suitable for loading into a data pipeline.
How many ICD-10 codes map to RxHCCs?
Roughly ten thousand of the ~74,000 ICD-10-CM codes map into the 84 RxHCC payment categories. The rest are not separately payable in Part D risk adjustment.
Can we automate this mapping across our population?
That is the core of what CuraFi does — member files in, RxHCCs, hierarchies, and 2026→2027 deltas out. Talk to us.