Gaps in disaster cost reporting and rising economic burdens in Canada, 1990-2020: retrospective database analysis.

Background: Disasters increasingly threaten population health and health-system resilience. Yet, the economic costs that inform preparedness and recovery remain unevenly measured. Missing cost data, particularly for rural and Indigenous communities, may contribute to inequities in disaster funding and response. We aimed to characterize disaster-related cost reporting and temporal trends in Canada (1990-2020), and to examine patterns of missing data across community contexts. Methods: We conducted a retrospective database analysis of federally recognized disasters in Canada (1990-2020) using the Findings: Between 1990 and 2020, meteorological (n = 402) and wildfire (n = 90) disasters accounted for most recorded losses in Canada, totalling CAD $38.3 billion (2020 value). Inflation-adjusted costs increased by 4.5% per year for meteorological events and 25.6% per year for wildfires. Among 636 total disaster events, only 278 (44%) had reported costs, revealing data gaps, with reporting completeness varying substantially over time. Cost reporting was lower for disasters affecting rural and Indigenous communities compared with urban/metro areas (56.0% vs 31.6%). Interpretation: Disaster costs in Canada are rising, driven by meteorological and wildfire events, yet more than half of recorded disasters lack cost data. These data gaps reflect limitations in disaster cost surveillance and reporting systems, with lower reporting observed for disasters affecting rural and Indigenous communities. Strengthening standardized and equity-sensitive disaster cost reporting should be recognized as a public-health and health-systems priority in an era of climate change. Funding: None.