Halizah (or chalitzah; Hebrew: חליצה) is, under the biblical system of levirate marriage known as yibbum, the process by which a childless widow and a brother of her deceased husband may avoid the duty to marry.

The process involves the widow making a declaration, taking off a shoe of the brother (i.e., her brother-in-law), and spitting on the floor. Through this ceremony, the brother and any other brothers are released from the obligation of marrying the woman for the purpose of conceiving a child which would be considered the progeny of the deceased man. The ceremony of chalitzah makes the widow free to marry whomever she desires, except for a Cohen (priest). (Deuteronomy 25:5–10).

It is sufficient for only one brother-in-law to perform the ceremony. The mode of levirate marriage (Genesis 38:8) is thus modified in the Deuteronomic code attributed to Moses, by permitting the surviving brother to refuse to marry his brother's widow, provided he submits to the ceremony of halitzah. In the Talmudic period the tendency against the original mode was intensified by apprehension that the brother-in-law might desire to marry his brother's widow for motives other than that of "establishing a name unto his brother." Therefore, many Talmudic and later rabbis preferred halitzah to actual marriage. Thus the ancient institution of the levirate marriage fell into disuse, so that at present halitzah is the general rule and marriage the rare exception.

In theory, however, the Biblical law of levirate marriage is still presumed in force, thus making the childless widow who remarries someone other than her brother-in-law without performing the halitzah ceremony an adulterer.