HCC 81: Ulcerative Colitis ICD-10-CM
CMS-HCC Category 81 (Ulcerative Colitis) is a payment HCC in the V28 Medicare Advantage risk adjustment model. For payment year 2026 it adds a risk adjustment factor between 0.201 and 0.286 to a beneficiary's RAF score depending on the payment segment (0.244 for a community, non-dual, aged enrollee). 49 ICD-10-CM diagnosis codes map to HCC 81. A more severe related category (HCC 77 and HCC 80) supersedes it when both are reported.
RAF Weight by Payment Segment 7 segments
| Payment Segment | Relative Factor |
|---|---|
| Community, non-dual, aged | 0.244 |
| Community, partial-benefit dual, aged | 0.205 |
| Community, full-benefit dual, aged | 0.201 |
| Community, non-dual, disabled | 0.285 |
| Community, partial-benefit dual, disabled | 0.237 |
| Community, full-benefit dual, disabled | 0.286 |
| Institutional | 0.258 |
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 77 (Intestine Transplant Status/Complications) and HCC 80 (Crohn's Disease (Regional Enteritis)) supersede HCC 81 when reported together.
ICD-10-CM Codes That Map to HCC 81 49 codes
- K51.00 Ulcerative (chronic) pancolitis without complications from V24 HCC 35
- K51.011 Ulcerative (chronic) pancolitis with rectal bleeding from V24 HCC 35
- K51.012 Ulcerative (chronic) pancolitis with intestinal obstruction from V24 HCC 33, HCC 35
- K51.013 Ulcerative (chronic) pancolitis with fistula from V24 HCC 35
- K51.014 Ulcerative (chronic) pancolitis with abscess from V24 HCC 35
- K51.018 Ulcerative (chronic) pancolitis with other complication from V24 HCC 35
- K51.019 Ulcerative (chronic) pancolitis with unspecified complications from V24 HCC 35
- K51.20 Ulcerative (chronic) proctitis without complications from V24 HCC 35
- K51.211 Ulcerative (chronic) proctitis with rectal bleeding from V24 HCC 35
- K51.212 Ulcerative (chronic) proctitis with intestinal obstruction from V24 HCC 33, HCC 35
- K51.213 Ulcerative (chronic) proctitis with fistula from V24 HCC 35
- K51.214 Ulcerative (chronic) proctitis with abscess from V24 HCC 35
- K51.218 Ulcerative (chronic) proctitis with other complication from V24 HCC 35
- K51.219 Ulcerative (chronic) proctitis with unspecified complications from V24 HCC 35
- K51.30 Ulcerative (chronic) rectosigmoiditis without complications from V24 HCC 35
- K51.311 Ulcerative (chronic) rectosigmoiditis with rectal bleeding from V24 HCC 35
- K51.312 Ulcerative (chronic) rectosigmoiditis with intestinal obstruction from V24 HCC 33, HCC 35
- K51.313 Ulcerative (chronic) rectosigmoiditis with fistula from V24 HCC 35
- K51.314 Ulcerative (chronic) rectosigmoiditis with abscess from V24 HCC 35
- K51.318 Ulcerative (chronic) rectosigmoiditis with other complication from V24 HCC 35
- K51.319 Ulcerative (chronic) rectosigmoiditis with unspecified complications from V24 HCC 35
- K51.40 Inflammatory polyps of colon without complications from V24 HCC 35
- K51.411 Inflammatory polyps of colon with rectal bleeding from V24 HCC 35
- K51.412 Inflammatory polyps of colon with intestinal obstruction from V24 HCC 33, HCC 35
- K51.413 Inflammatory polyps of colon with fistula from V24 HCC 35
- K51.414 Inflammatory polyps of colon with abscess from V24 HCC 35
- K51.418 Inflammatory polyps of colon with other complication from V24 HCC 35
- K51.419 Inflammatory polyps of colon with unspecified complications from V24 HCC 35
- K51.50 Left sided colitis without complications from V24 HCC 35
- K51.511 Left sided colitis with rectal bleeding from V24 HCC 35
- K51.512 Left sided colitis with intestinal obstruction from V24 HCC 33, HCC 35
- K51.513 Left sided colitis with fistula from V24 HCC 35
- K51.514 Left sided colitis with abscess from V24 HCC 35
- K51.518 Left sided colitis with other complication from V24 HCC 35
- K51.519 Left sided colitis with unspecified complications from V24 HCC 35
- K51.80 Other ulcerative colitis without complications from V24 HCC 35
- K51.811 Other ulcerative colitis with rectal bleeding from V24 HCC 35
- K51.812 Other ulcerative colitis with intestinal obstruction from V24 HCC 33, HCC 35
- K51.813 Other ulcerative colitis with fistula from V24 HCC 35
- K51.814 Other ulcerative colitis with abscess from V24 HCC 35
- K51.818 Other ulcerative colitis with other complication from V24 HCC 35
- K51.819 Other ulcerative colitis with unspecified complications from V24 HCC 35
- K51.90 Ulcerative colitis, unspecified, without complications from V24 HCC 35
- K51.911 Ulcerative colitis, unspecified with rectal bleeding from V24 HCC 35
- K51.912 Ulcerative colitis, unspecified with intestinal obstruction from V24 HCC 33, HCC 35
- K51.913 Ulcerative colitis, unspecified with fistula from V24 HCC 35
- K51.914 Ulcerative colitis, unspecified with abscess from V24 HCC 35
- K51.918 Ulcerative colitis, unspecified with other complication from V24 HCC 35
- K51.919 Ulcerative colitis, unspecified with unspecified complications from V24 HCC 35
Every code above carries the full HCC 81 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 81
What is HCC 81 in the CMS-HCC model?
HCC 81 is CMS-HCC Category 81 (Ulcerative Colitis) in the V28 risk adjustment model. It covers 49 ICD-10-CM diagnosis codes that raise a Medicare Advantage beneficiary's risk score when documented.
What is the RAF weight for HCC 81?
For payment year 2026, HCC 81 adds 0.244 to the RAF score of a community, non-dual, aged beneficiary (living at home, age 65 or over, not also enrolled in Medicaid). The published weights range from 0.201 to 0.286 across the seven payment segments shown above.
Which categories supersede HCC 81?
HCC 77 (Intestine Transplant Status/Complications) and HCC 80 (Crohn's Disease (Regional Enteritis)) sit above HCC 81 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.
