Standard Tier Module
PDPM SNF Per-Diem Rate Calculator
A deterministic, in-browser calculator for the Medicare Part A skilled-nursing per-diem under the Patient-Driven Payment Model (PDPM; 42 CFR 413.337, CMS SNF PPS).
See it run - a worked example, 100% in this browser tab
What it is
A deterministic, in-browser calculator for the Medicare Part A skilled-nursing per-diem under the Patient-Driven Payment Model (PDPM; 42 CFR 413.337, CMS SNF PPS). The per-diem is the sum of six components - PT, OT, SLP, Nursing, NTA, and a non-case-mix component - each paid as (unadjusted federal base rate, urban or rural) x (the component case-mix index for the patient's case-mix group) x (the variable-per-diem factor for the day of stay). It applies the published variable-per-diem schedule exactly: PT and OT pay 100% through day 20 then decline 2 percentage points every 3 days; NTA pays 300% on days 1-3 then 100%; SLP, Nursing, and non-case-mix pay 100% every day. No API, no key, no network, no AI - every figure is exact arithmetic citing its rule. The base rates and CMIs are DATED CMS inputs you confirm for the federal fiscal year (defaulted to a cited FY2025 as-of value); a wrong fiscal year never silently mis-computes because the rates, CMIs, and factors used are always shown. Not legal, billing, reimbursement, or clinical advice.
Honest scope
Deterministic and citation-backed: every figure is exact arithmetic or a cited rule. Any year- or jurisdiction-indexed value is a confirmable input, never an eternal hardcode. This is a computation tool, not professional (legal, tax, medical, or financial) advice - confirm against the controlling authority for your context.
Authorities cited
- 42 CFR 413.337 - Methodology used for the calculation of the prospective payment rates (SNF PPS), including the case-mix adjustment and the variable per-diem adjustment under PDPM.
- Social Security Act 1888(e) (42 U.S.C. 1395yy(e)) - The SNF prospective payment system: the federal per-diem base rates, case-mix adjustment, and geographic wage-index adjustment.
- CMS SNF PPS PDPM methodology - Per-diem = sum over the six PDPM components of (unadjusted federal base per-diem rate, urban or rural) x (component case-mix index for the case-mix group) x (variable-per-diem factor for the day of stay); the non-case-mix component has no CMI.
- CMS-1802-F, FY2025 SNF PPS Final Rule, 89 FR 64280 (Aug 6, 2024) - The FY2025 unadjusted federal base per-diem rates (urban and rural) used as the cited defaults here; effective Oct 1, 2024 - Sep 30, 2025. Confirm the rates for your fiscal year.
- CMS PDPM variable per-diem (VPD) schedule (42 CFR 413.337(d)) - PT and OT: 100% for days 1-20, then -2 percentage points every 3 days; NTA: 300% for days 1-3, then 100%; SLP, Nursing, and non-case-mix: 100% every day.
- CMS SNF PPS PDPM case-mix index (CMI) tables (FY final rule) - The published CMI for each component case-mix group (CMG); the MDS-driven PDPM grouper assigns the CMG, which is NOT performed here (you supply the resulting CMI per component).
- CMS PDPM Calculation Worksheet for SNFs (MLN / SNF PPS PDPM resources) - The step-by-step component-by-component per-diem worksheet this calculator reproduces, excluding the geographic wage-index adjustment and add-ons.
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Run it on your own data
Open it inside GDBS to save runs to Sandbox, attach results to a Worklog case, or share through a Gate client portal - all in the browser, nothing uploaded to anyone’s cloud.