邮镇（post town）是英国邮编系统中最基本的单位之一。 邮镇填写正确与否直接决定了邮件能否顺利送达。现在其主要作用是区分没有邮编的地点或街道。

英国现有大约1,500个邮镇，由皇家邮政统一管理。 每一个邮镇对应一个或多个postal districts，涵盖城市、小镇及村庄。一般与行政边界并不重叠而是取决于实际情况，因此常常跨郡、国会选区和教区。这也是原来英国的邮郡渐渐废弃的缘故之一。 另外一些地区，一个postal district有多个邮镇。

A post town is a required part of all postal addresses in the United Kingdom, and a basic unit of the postal delivery system. Including the correct post town in the address increases the chance of a letter or parcel being delivered on time. Post towns in general originated as the location of delivery offices. Currently their main function is to distinguish between locality or street names in addresses not including a postcode.