This study examines the impact of superstition on corporate decision-making in Vietnam, a highly irreligious country. We focus on the folk belief that the ages of 49–53 are considered calamitous and use a regression discontinuity design to show that companies significantly decrease their investment in fixed assets during these ages of their directors. The effect is more pronounced in smaller firms and is not accompanied by a decrease in employment growth. We introduce a novel two-stage difference method to identify the role of superstition in causing the ‘calamitous ages’ effect.