Relative factors by segment
Each segment is a separate regression; the factor is added to the beneficiary's demographic factors and other categories, then normalized and reduced by the coding intensity adjustment before it meets the plan's base rate. A factor of 1.000 equals the expected cost of an average beneficiary.
| Segment | Model code | Relative factor |
|---|---|---|
| Community, non-dual, aged | CNA_HCC249 | 0.239 |
| Community, non-dual, disabled | CND_HCC249 | 0.180 |
| Community, full-benefit dual, aged | CFA_HCC249 | 0.377 |
| Community, full-benefit dual, disabled | CFD_HCC249 | 0.277 |
| Community, partial-benefit dual, aged | CPA_HCC249 | 0.299 |
| Community, partial-benefit dual, disabled | CPD_HCC249 | 0.172 |
| Long-term institutional | INS_HCC249 | 0.081 |
Hierarchy
Hierarchical condition categories pay only the most severe manifestation of a disease. When HCC 248 (Intracranial Hemorrhage) is also documented for the same beneficiary, HCC 249 is dropped from the score.
ICD-10-CM codes that map to HCC 249
95 codes map to this category in the PY2027 initial mapping, concentrated in the I63 (91), P91 (4) code families. Descriptions are the CMS mapping descriptions for the FY2026 code set; a code that is deleted or split in the October code update stays valid for dates of service before the change.
| ICD-10-CM | Description |
|---|---|
| I6300 | Cerebral infarction due to thrombosis of unspecified precerebral artery |
| I63011 | Cerebral infarction due to thrombosis of right vertebral artery |
| I63012 | Cerebral infarction due to thrombosis of left vertebral artery |
| I63013 | Cerebral infarction due to thrombosis of bilateral vertebral arteries |
| I63019 | Cerebral infarction due to thrombosis of unspecified vertebral artery |
| I6302 | Cerebral infarction due to thrombosis of basilar artery |
| I63031 | Cerebral infarction due to thrombosis of right carotid artery |
| I63032 | Cerebral infarction due to thrombosis of left carotid artery |
| I63033 | Cerebral infarction due to thrombosis of bilateral carotid arteries |
| I63039 | Cerebral infarction due to thrombosis of unspecified carotid artery |
| I6309 | Cerebral infarction due to thrombosis of other precerebral artery |
| I6310 | Cerebral infarction due to embolism of unspecified precerebral artery |
| I63111 | Cerebral infarction due to embolism of right vertebral artery |
| I63112 | Cerebral infarction due to embolism of left vertebral artery |
| I63113 | Cerebral infarction due to embolism of bilateral vertebral arteries |
| I63119 | Cerebral infarction due to embolism of unspecified vertebral artery |
| I6312 | Cerebral infarction due to embolism of basilar artery |
| I63131 | Cerebral infarction due to embolism of right carotid artery |
| I63132 | Cerebral infarction due to embolism of left carotid artery |
| I63133 | Cerebral infarction due to embolism of bilateral carotid arteries |
| I63139 | Cerebral infarction due to embolism of unspecified carotid artery |
| I6319 | Cerebral infarction due to embolism of other precerebral artery |
| I6320 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified precerebral arteries |
| I63211 | Cerebral infarction due to unspecified occlusion or stenosis of right vertebral artery |
| I63212 | Cerebral infarction due to unspecified occlusion or stenosis of left vertebral artery |
| I63213 | Cerebral infarction due to unspecified occlusion or stenosis of bilateral vertebral arteries |
| I63219 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified vertebral artery |
| I6322 | Cerebral infarction due to unspecified occlusion or stenosis of basilar artery |
| I63231 | Cerebral infarction due to unspecified occlusion or stenosis of right carotid arteries |
| I63232 | Cerebral infarction due to unspecified occlusion or stenosis of left carotid arteries |
| I63233 | Cerebral infarction due to unspecified occlusion or stenosis of bilateral carotid arteries |
| I63239 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified carotid artery |
| I6329 | Cerebral infarction due to unspecified occlusion or stenosis of other precerebral arteries |
| I6330 | Cerebral infarction due to thrombosis of unspecified cerebral artery |
| I63311 | Cerebral infarction due to thrombosis of right middle cerebral artery |
| I63312 | Cerebral infarction due to thrombosis of left middle cerebral artery |
| I63313 | Cerebral infarction due to thrombosis of bilateral middle cerebral arteries |
| I63319 | Cerebral infarction due to thrombosis of unspecified middle cerebral artery |
| I63321 | Cerebral infarction due to thrombosis of right anterior cerebral artery |
| I63322 | Cerebral infarction due to thrombosis of left anterior cerebral artery |
| I63323 | Cerebral infarction due to thrombosis of bilateral anterior cerebral arteries |
| I63329 | Cerebral infarction due to thrombosis of unspecified anterior cerebral artery |
| I63331 | Cerebral infarction due to thrombosis of right posterior cerebral artery |
| I63332 | Cerebral infarction due to thrombosis of left posterior cerebral artery |
| I63333 | Cerebral infarction due to thrombosis of bilateral posterior cerebral arteries |
| I63339 | Cerebral infarction due to thrombosis of unspecified posterior cerebral artery |
| I63341 | Cerebral infarction due to thrombosis of right cerebellar artery |
| I63342 | Cerebral infarction due to thrombosis of left cerebellar artery |
| I63343 | Cerebral infarction due to thrombosis of bilateral cerebellar arteries |
| I63349 | Cerebral infarction due to thrombosis of unspecified cerebellar artery |
| I6339 | Cerebral infarction due to thrombosis of other cerebral artery |
| I6340 | Cerebral infarction due to embolism of unspecified cerebral artery |
| I63411 | Cerebral infarction due to embolism of right middle cerebral artery |
| I63412 | Cerebral infarction due to embolism of left middle cerebral artery |
| I63413 | Cerebral infarction due to embolism of bilateral middle cerebral arteries |
| I63419 | Cerebral infarction due to embolism of unspecified middle cerebral artery |
| I63421 | Cerebral infarction due to embolism of right anterior cerebral artery |
| I63422 | Cerebral infarction due to embolism of left anterior cerebral artery |
| I63423 | Cerebral infarction due to embolism of bilateral anterior cerebral arteries |
| I63429 | Cerebral infarction due to embolism of unspecified anterior cerebral artery |
| I63431 | Cerebral infarction due to embolism of right posterior cerebral artery |
| I63432 | Cerebral infarction due to embolism of left posterior cerebral artery |
| I63433 | Cerebral infarction due to embolism of bilateral posterior cerebral arteries |
| I63439 | Cerebral infarction due to embolism of unspecified posterior cerebral artery |
| I63441 | Cerebral infarction due to embolism of right cerebellar artery |
| I63442 | Cerebral infarction due to embolism of left cerebellar artery |
| I63443 | Cerebral infarction due to embolism of bilateral cerebellar arteries |
| I63449 | Cerebral infarction due to embolism of unspecified cerebellar artery |
| I6349 | Cerebral infarction due to embolism of other cerebral artery |
| I6350 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified cerebral artery |
| I63511 | Cerebral infarction due to unspecified occlusion or stenosis of right middle cerebral artery |
| I63512 | Cerebral infarction due to unspecified occlusion or stenosis of left middle cerebral artery |
| I63513 | Cerebral infarction due to unspecified occlusion or stenosis of bilateral middle cerebral arteries |
| I63519 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified middle cerebral artery |
| I63521 | Cerebral infarction due to unspecified occlusion or stenosis of right anterior cerebral artery |
| I63522 | Cerebral infarction due to unspecified occlusion or stenosis of left anterior cerebral artery |
| I63523 | Cerebral infarction due to unspecified occlusion or stenosis of bilateral anterior cerebral arteries |
| I63529 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified anterior cerebral artery |
| I63531 | Cerebral infarction due to unspecified occlusion or stenosis of right posterior cerebral artery |
| I63532 | Cerebral infarction due to unspecified occlusion or stenosis of left posterior cerebral artery |
| I63533 | Cerebral infarction due to unspecified occlusion or stenosis of bilateral posterior cerebral arteries |
| I63539 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified posterior cerebral artery |
| I63541 | Cerebral infarction due to unspecified occlusion or stenosis of right cerebellar artery |
| I63542 | Cerebral infarction due to unspecified occlusion or stenosis of left cerebellar artery |
| I63543 | Cerebral infarction due to unspecified occlusion or stenosis of bilateral cerebellar arteries |
| I63549 | Cerebral infarction due to unspecified occlusion or stenosis of unspecified cerebellar artery |
| I6359 | Cerebral infarction due to unspecified occlusion or stenosis of other cerebral artery |
| I636 | Cerebral infarction due to cerebral venous thrombosis, nonpyogenic |
| I6381 | Other cerebral infarction due to occlusion or stenosis of small artery |
| I6389 | Other cerebral infarction |
| I639 | Cerebral infarction, unspecified |
| P91821 | Neonatal cerebral infarction, right side of brain |
| P91822 | Neonatal cerebral infarction, left side of brain |
| P91823 | Neonatal cerebral infarction, bilateral |
| P91829 | Neonatal cerebral infarction, unspecified side |
Where these codes sat in the V22 model
The V28 recalibration renumbered and regrouped categories; this table shows which legacy V22 categories the same ICD-10 codes belonged to, which is the quickest way to reconcile a V22-era HCC gap list with the current model.
| V22 HCC | Codes |
|---|---|
| 100 | 95 |
Capturing and defending the category
A category counts for a payment year when a mapped diagnosis is documented at least once during the data collection year by an acceptable provider type at a face-to-face or audio-video encounter, and when the note shows the condition was monitored, evaluated, assessed or treated. Chronic conditions do not carry forward: a category that is not re-documented in the year drops out of the score, which is why annual wellness visits and problem-list reconciliation are where most recapture happens. Risk adjustment data validation audits sample enrollees and ask for the medical record behind each submitted category; an unsupported category is removed and, under the extrapolation rules, the error rate is applied across the contract. The QuickIntell risk adjustment product surfaces suspected and unsupported categories from the chart, and the HCC hub lists every V28 category with its factor and code count.
Frequently asked questions
Which ICD-10 codes map to HCC 249?
95 ICD-10-CM codes map to HCC 249 in the CMS PY2027 initial mapping, for example I6300 Cerebral infarction due to thrombosis of unspecified precerebral artery; I63011 Cerebral infarction due to thrombosis of right vertebral artery; I63012 Cerebral infarction due to thrombosis of left vertebral artery; I63013 Cerebral infarction due to thrombosis of bilateral vertebral arteries. The full list is on this page; a code counts only when it is documented at a face-to-face or video encounter in the data collection year and supported by the record.
How much does HCC 249 add to a risk score?
The V28 relative factor for HCC 249 is 0.239 for a community, non-dual, aged beneficiary, 0.377 for full-benefit dual aged, 0.180 for non-dual disabled and 0.081 for long-term institutional members. A factor of 1.000 equals the expected annual cost of an average beneficiary, so the category's share of the payment follows the plan's base rate for that segment.
Does HCC 249 count together with related categories?
No. Within a hierarchy only the most severe category is paid. HCC 249 is dropped when HCC 248 (Intracranial Hemorrhage) is also present.
What has to be documented for HCC 249 to be valid?
The diagnosis must be recorded by an acceptable provider type during a face-to-face or audio-video encounter in the service year, with the note showing that the condition was monitored, evaluated, assessed or treated. Risk adjustment data validation audits recover payment for categories the record does not support, so the code on the claim and the assessment in the note must match.
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-02. Verify against the primary file before billing or contracting decisions.
- ICD-10-CM to CMS-HCC V28 mappings, payment year 2027 initialVersion PY2027 initial ICD-10-CM mappings (dates of service 2026) · effective 2027-01-01 · file 2027 Initial ICD-10-CM Mappings.csvSHA-256 9c260b06d0dd2806…
- CMS-HCC V28 model software: labels, hierarchies and relative factorsVersion CMS-HCC V28 software V2826.115.T2 (PY2027 initial) · effective 2027-01-01 · file C2824T2N.csvSHA-256 20f38d537493b41c…
Disclaimer
Relative factors and mappings are reproduced from the CMS risk adjustment model files as an operational reference. Payment depends on the plan's base rate, normalization, the coding intensity adjustment and the enrollee's segment. Not legal, clinical or billing advice.