Submission Deadlines
Completed Premiums Workbooks and federal MLR forms are due no later than Wednesday, September 9, 2026.
Completed Supplemental Workbooks are due no later than Wednesday, September 23, 2026.
All forms must be submitted to CHIAData@oliverwyman.com
Reporting Requirements
Two Excel workbooks must be used for data submission:
Health Care Payers Premiums and Claims Data Reporting Workbook (Premiums Workbook)
A Premiums Workbook must be completed for each legal entity of a payer and saved according to the file naming convention “2026-PremiumsReporting-Carrier Designator-YYYYMMDD.xlsx.” Standardized carrier designator abbreviations are listed in the “Naming Conventions” tab in the workbook. Payers are responsible for notifying CHIA of additional legal entities not listed here that may meet filing requirements.
Supplemental Data Reporting Workbook (Supplemental Workbook)
A Supplemental Workbook must be completed for each legal entity of a payer and saved according to the file naming convention “2026-Supplemental-Data-Reporting-Carrier Designator-YYYYMMDD.xlsx. Standardized carrier designator abbreviations are listed in the “Naming Conventions” tab of the Supplemental Workbook. Payers are responsible for notifying CHIA of additional legal entities not listed here that may meet filing requirements.
Additional Requirement: Federal MLR forms
In addition to the CHIA-required workbooks, payers should submit copies of their completed Centers for Medicare & Medicaid Services (CMS) Medical Loss Ratio (MLR) Annual Reporting Form for the 2025 MLR Reporting Year. These forms should be submitted in both PDF and Excel format.
Recommended Links
CHIA Regulations (CMR)
Access CHIA's regulations governing health care data collection and reporting in Massachusetts, including current rules, administrative bulletins, and hearings.
Payer Expenditure & Utilization Data
CHIA’s aggregate payer data collects information from commercial health insurance plans in Massachusetts to support a better understanding of health care costs, spending trends, and how care is delivered across the state.
Commercial Premiums and Member Cost-Sharing
Annual data on health premiums is used to show costs for Massachusetts employers and workers and to track high-deductible plans and out-of-pocket costs.