Today we will discuss when does the ceremony of Pidyon takes place? In the Tora says: (Numbers 18:16) ufduyav miben chodesh tifde... ( from a month old, you shall redeem them...), which means that the Pidyon is done only after the baby is one-month old. The Pidyon is celebrated on the thirty-one day from birth. The ceremony is done at night, when the day thirty-one begins. According to some opinions the Pidyon should be made specifically during the day (Shakh). In Sephardic communities, however, the Pidyon is done normally at night. To establish the day thirty-one, we consider as day number one, the day of birth. It is essential to know, therefore, the exact time the baby was born to determine what was the day of the week the baby was born. The date of the Pidyon would always fall four weeks and two days after the day of birth. If the baby was born on a Monday morning, for example, the Pidyon will take place on Tuesday night, since for the Jewish calendar Tuesday night is considered Wednesday. (As it is well known, the new day in the Hebrew calendar begins after the sundown of the previous day). Because all these considerations and other technical details, it is highly recommended to speak with a Rabbi to set the exact day of the Pidyon ceremony.