World Health Organization age-, sex-, and cause-specific mortality data for the United States and 19 other democratic higher-income countries were utilized to assess the reliability and sensitivity of suicide certification for purposes of cross-national research. Data are found to be highly reliable across age and sex (rs > 0.92; P < 0.001). Relative discrepancies between official suicide rates (putative lower limits) and projected upper limits vary widely internationally. Austrian and Dutch suicide certification is the most sensitive. Least sensitive is certification for certain subpopulations in Finland, Greece, Ireland, Israel, and the United Kingdom. We recommend similar analyses be performed for routine, low-cost surveillance of suicide data quality, and to guide choice of population groups for multivariate comparative research.