CMS-1845-F

**ATTENTION: On 08/21/2026, CMS replaced the “FY 2027 Tier Comorbidities – ICD-10 Appendix C List” file with the revised file “FY 2027 Tier Comorbidities – ICD-10 Appendix C List.V2_8.20.2026” in the associated files.

This rule (CMS-1845-F) is on public display at the Office of the Federal Register.

The associated file(s) (ZIP) are described below:

• IRF Wage Index Final Rule - These files contain the final urban and rural Core-Based Statistical Area FY 2027 IRF wage index tables.
• IRF Rate Setting Final Rule - This file contains data for each of the 1,178 inpatient rehabilitation facilities used to estimate the policy updates in the final inpatient rehabilitation prospective payment system regulation. The methodology used to update the payment data is described in detail in the final rule.
• Case-Mix Groups, Relative Weights, and Average Length of Stay - Values used in the final rule and the standard deviations from the average lengths of stay.
• Tier Comorbidities – ICD-10-CM - This file contains the list of diagnoses (ICD-10-CM codes) that are used to determine placement in tiers for IRF discharges, effective October 1, 2026. It contains the ICD-10-CM codes, the abbreviated code labels, the appropriate tier, and any RICs for which the ICD-10-CM codes are excluded from the tiers (Updated to reflect ICD-10-CM code label changes for October 1, 2026).
• Tier Comorbidities Changes - This revised file contains the list of diagnoses (ICD-10-CM codes) that are used to determine placement in tiers for IRF discharges, effective October 1, 2026. It contains the ICD-10-CM codes, the abbreviated code labels, the appropriate tier, and any RICs for which the ICD-10-CM codes are excluded from the tiers (Updated to reflect ICD-10-CM code label changes for October 1, 2026).
• Presumptive Compliance-3 (ICD-10-CM) - This file contains the list of diagnoses (ICD-10-CM codes) that are used for determining presumptive compliance with the IRF 60 percent rule, effective for discharges beginning on or after October 1, 2026. (There are no ICD-10-CM coding updates to this file for October 1, 2026)
• Impairment Group Codes That Meet Presumptive Compliance Criteria-3 (ICD-10-CM) - This file contains the list of impairment group codes that are used for determining presumptive compliance with the IRF 60 percent rule, effective for discharges beginning on or after October 1, 2026. (This file includes a technical correction to replace obsolete ICD-10-CM code M48.06 with ICD-10-CM codes M48.061 and M48.062. There are no other ICD-10-CM coding updates to this file for October 1, 2026).
• IRF Technical Reports for Payment Reform Research – These technical reports describe the Primary Diagnosis classification and Comorbidity approach as part of IRF PPS payment reform request for information. The ICD-10-CM to clinical category mappings are simulated for research purposes only and support analysis of the alternative IRF PPS Primary Diagnosis classification system described in the IRF Payment Reform Request for Information (RFI) in the IRF PPS FY 2027 Proposed Rule.