结婚启事（英语：banns of marriage，英文简称「banns」或「bans」），是一种源于基督宗教，由教区教堂发出的公开告示，目的在于向外公布该所教堂在未来举行的婚礼。结婚启事较常见于英国圣公会和其他类似的基督教宗派，罗马天主教教会则于1983年废除结婚启事。

结婚启事的作用是把婚讯在婚礼举行前的一段时间公开，由此可让任何人有充足的时间依据教会法或民事法对婚事提出质疑，从而避免出现不合宜和不正当的婚姻。各地质疑婚姻正当性的考虑因素都有差异，但主要的质疑理据包括，男女任何一方未完全解除或废止前一段婚姻、男女任何一方曾作出独身的承诺、男女双方没有同意缔结婚姻、或男女双方为近亲等。

The banns of marriage, commonly known simply as the "banns" or "bans" /bænz/ (from a Middle English word meaning "proclamation," rooted in Frankish and from there to Old French), are the public announcement in a Christian parish church or in the town council of an impending marriage between two specified persons. It is commonly associated with the Church of England and with other denominations whose traditions are similar; in 1983, the Roman Catholic Church removed the requirement for banns and left it to individual national conferences of bishops to decide whether to continue this practice.