The article examines how different calendar effects impact the Tunisian stock market. It looks at four specific effects: the weekend effect, end of the month effect, January effect, and Ramadhan effect. The study finds that these anomalies do exist in the Tunisian market, with significant variations in returns between different days of the week and during the holy month of Ramadhan. The findings suggest that political regimes can also influence these effects on stock market behavior.