Part D now has more than one payable model. Which one applies depends on the plan, not on the codes.
Through CY2026 a single RxHCC model priced every Part D contract. For CY2027 CMS recalibrated it on 2023/2024 data and split it, so an MA-PD plan and a stand-alone PDP are now scored with different relative factors for the same diagnoses. PACE organizations stay on the older 2018/2019 calibration.
None of this changes which diagnosis reaches which RxHCC. It changes what the category is worth, and to whom.
| Applies to | Calibration | Normalisation | Package |
|---|---|---|---|
| MA-PD plans | 2023/2024 | 1.109 | Y1 or Y2 ? |
| Stand-alone PDPs | 2023/2024 | 1.005 | the other of Y1 / Y2 ? |
| PACE organizations | 2018/2019 | 1.237 | T2 |
Normalisation factors are from the CY2027 Rate Announcement. CMS divides the raw score by this figure, so the same diagnoses land on a different final score for an MA-PD plan than for a PDP before the relative factors are even considered.
CMS distributes the 2023/2024 models as two packages named Y1
and Y2, and nothing inside either says which is MA-PD and
which is PDP. The configuration files repeat the letter, the readmes are
identical, the descriptions ship as binary documents. The third package,
T2, is identifiable: its coefficients match the 2026 release
to three decimals, which makes it the 2018/2019 calibration.
So this page does not tell you which letter to use, and this tool scores neither of them. An inference is available from the normalisation factors; it is not good enough to decide a payment coefficient on. Confirm the pairing against the Rate Announcement's own factor tables before you load one.
For PACE organizations CMS blends the model finalised for non-PACE organizations with the 2018/2019 calibration rather than moving them onto the recalibrated model outright. A PACE score is two scores combined, and neither half on its own is the payable number.
Since CY2022, risk scores for payment to Part D sponsors at non-PACE organizations use only risk-adjustment-eligible diagnoses from encounter data and FFS claims, and CMS is excluding diagnoses identified as resulting from audio-only telehealth.
That is a rule about where a diagnosis came from, and a code carries no memory of where it came from. Two identical code lists, one submitted through encounter data and one not, produce different payable scores. No encoder can tell them apart, and that includes this one.
What this tool does show is the mapping — which RxHCC a diagnosis reaches — and that has not changed for 2027. FY2026 and FY2027 carry the same 5,527 RxHCC mappings. The risk calculator continues to score RxHCC on the 2026 model, which is the last one attributable to a plan type with certainty.
The Announcement of Calendar Year 2027 Medicare Advantage Capitation Rates and Part C and Part D Payment Policies, and the CY2027 risk adjustment implementation information. Figures here are read from those documents and from the model software packages themselves, not from secondary summaries.
