Objectives: To assess the short-term temporal variations in suicide risk related to the day-of-the week and national holidays in multiple countries. Design: Two-stage time-series design. Setting: Data from 740 locations in 26 countries/territories, with overlapping periods between 1971 and 2019, collected from the Multi-City Multi-Country Collaborative Research Network database. Participants All suicides were registered in these locations during the study period (overall 1,701,487 cases). Main outcome measures: Daily suicide mortality. Results: Mondays demonstrated a peak in suicide risk during weekdays (Monday-Friday) across all countries, with Relative Risks [RRs] (reference: Wednesday) ranging from 1.02 (95% CI: 0.95 to 1.10) in Costa Rica to 1.17 (95% CI: 1.09 to 1.25) in Chile. Suicide risks were lowest on Saturdays or Sundays in many countries in North America, Asia, and Europe. However, the risk increased during weekends in South-Central American countries, Finland, and South Africa. In addition, we found strong evidence of increased suicide risk on New Year’s Day in most countries with RRs ranging from 0.93 (95% CI: 0.75 to 1.14) in Japan to 1.93 (95% CI: 1.31 to 2.85) in Chile, whereas the evidence on Christmas was weak. Finally, suicide risk showed a weak decreasing pattern on other national holidays (excluding New Year’s Day and Christmas), except for Central and South American countries, where the risk generally increased one or two days after the holidays. Conclusions: We found that the suicide risk was highest on Mondays and increased on New Year’s Day in most countries. However, the risk of suicide on weekends and Christmas varied by country/territory. The results of this study can help better understand the short-term variations in suicide risks and define suicide prevention action plans and awareness campaigns.