How many times is Passover mentioned in the Old Testatement?

Passover is mentioned multiple times in the Old Testament, with significant references found in the books of Exodus, Leviticus, Numbers, and Deuteronomy. The most notable accounts are in Exodus 12, which details the original Passover event, and subsequent instructions for its observance. Overall, Passover is directly referenced around 15 times throughout the Old Testament.