CMS Corrects FY 2027 Hospital Payment Math Two Days Before It Takes Effect

CMS published a 16-page correction to its fiscal 2027 hospital payment rule on September 29, with the changes effective October 1. The agency says it is not changing policy or payment methodology, but the repair reaches far beyond stray punctuation: two hospital-status errors flowed through national wage indexes, payment factors, and uncompensated-care calculations.

What It Is

The final-rule correction, published at 91 FR 61328 under dockets CMS-1849-CN3 and CMS-0062-CN and RINs 0938-AV44 and 0938-AV79, amends the mammoth inpatient prospective payment system and long-term care hospital rule issued August 4. CMS says the corrections apply to discharges on or after October 1 as though they had appeared in the original rule. It is proceeding without a new notice-and-comment period because it characterizes the changes as technical and typographical and says prompt correction is needed for accurate payments.

What’s Changing

CMS says it mistakenly treated one current inpatient hospital, identified as CCN 250078, as though it had converted to rural emergency hospital status. That excluded the hospital’s data from several fiscal 2027 calculations. The agency also treated another hospital, CCN 360068, as rural after the hospital had timely canceled that classification request.

Fixing those records required CMS to recalculate Medicare severity diagnosis-related group relative weights, wage indexes, geographic adjustment factors, budget-neutrality factors, the outlier fixed-loss threshold, standardized payment amounts, and the capital federal rate. CMS also recalculated the uncompensated-care Factor 3 for every hospital eligible for disproportionate-share payments after restoring one hospital’s eligibility and correcting merger data for four others. Updated IPPS and LTCH payment tables have been posted by CMS.

The document makes a few narrow corrections to the Medicare Promoting Interoperability Program, including wording around certification criteria at 45 CFR 170.315 and the applicable electronic health record reporting period. Despite the health-IT language in the rule’s title, this is chiefly a payment-data correction, not a new interoperability policy.

Why It Matters

For hospital finance and reimbursement teams, “correction” is doing a heroic amount of work. A pair of classification mistakes altered inputs used across national ratesetting, so organizations should use the revised tables when modeling fiscal 2027 payments rather than assuming the August files remain authoritative. CMS says most changes to uncompensated-care Factor 3 are limited in magnitude, but hospital-specific effects can differ, and the corrected wage indexes and relative weights feed directly into payment calculations.

Physicians and patients will not see a new coverage rule here. The practical issue is whether hospitals begin the fiscal year using the right numbers—and whether a two-day runway feels generous to anyone outside the Federal Register’s native habitat.

Read the final-rule correction in the Federal Register (https://www.federalregister.gov/documents/2026/09/29/2026-19946/medicare-program-hospital-inpatient-prospective-payment-systems-for-acute-care-hospitals-ipps-and)