A system-wide banking crisis increases population heart disease mortality rates by 6.4% (95% CI: 2.5% to 10.2%, p<0.01) in high income countries, after controlling for economic change, macroeconomic instability, and population age and social distribution. The estimated effect is nearly four times as large in low income countries. Conclusions Banking crises are a significant determinant of short-term increases in heart disease mortality rates, and may have more severe consequences for developing countries.