国际金融业务分行（英语：Offshore Banking Unit，简称OBU，又称离岸银行或境外银行）指存款人在其居住地境外开设账户的银行（相反，位于存款人所居住国内的银行则称为「在岸银行」或「境内银行」），通常赋税较低（或免税），具备财务与法律优势。

境外（offshore）一词源自英国海峡群岛，现在大部分境外分行都设立在岛国，所以境外已成为此类银行的象征意义，与所在地已无必然关联（瑞士、卢森堡和安道尔共和国是位于内陆的特例）

An offshore bank is a bank located outside the country of residence of its depositors, with most of its account holders being non-residents of the jurisdiction. An account held in a foreign account, especially in a tax haven country, is often described as an offshore account. Typically, an individual or company will maintain an offshore account in a low-tax jurisdiction (or tax haven) that provides financial and legal advantages, such as: