Chametz acquired on Passover

Hello,

One who is given a gift of Chametz during Passover (such as samples which come in the mail) should indicate, with a verbal declaration and with his actions, that he does not want to acquire the gift. He should not store it on his property.

However, if the deliverer (such as the mailman) simply puts the item down in one's house, without having been told to do so, then the Jew may leave it there through Passover. He should put a cover over it to prevent people from accidentally taking it or using it, and he should state that he is not acquiring it, and he may then leave it there until after Passover, after which he may take it and use it.

(Code of Jewish Law Orach Chaim 448:2; Mishneh Berurah 448:5)

Have a great day,
Mordechai