英国英语（British English，简写：BrE、BE、en-GB），又称英式英语，主要是指居住在不列颠群岛上的英格兰人的英语规则，为英国本土及英联邦国家的官方语言。

英式英语并非为所有英国人认同。在某些非英格兰地区，特别是苏格兰、威尔士与爱尔兰，主张不同方言之共存。他们认为强行统一英语等于无理羞辱。然而，对于英格兰人而言，他们认为不必将方言的进化看得太严肃。

历史上，英语之所以世界通行，全都是因为大英帝国的势力，且最有代表影响力的英国英语，又称「英国腔」，但仍然有许多国家却不这么认为（特别是美国）。

British English is the English language as spoken and written in Great Britain or, more broadly, throughout the British Isles. Slight regional variations exist in formal, written English in the United Kingdom. For example, the adjective wee is almost exclusively used in parts of Scotland and Northern Ireland, whereas little is predominant elsewhere. Nevertheless, there is a meaningful degree of uniformity in written English within the United Kingdom, and this could be described by the term British English. The forms of spoken English, however, vary considerably more than in most other areas of the world where English is spoken, so a uniform concept of British English is more difficult to apply to the spoken language. According to Tom McArthur in the Oxford Guide to World English, British English shares "all the ambiguities and tensions in the word British and as a result can be used and interpreted in two ways, more broadly or more narrowly, within a range of blurring and ambiguity."