Iranians in the United Kingdom are referred to by hyphenated terms such as British-Iranians, British-Persians, Iranian-Britons, or Persian-Britons.

[6][7] British-Iranian is used interchangeably with British-Persian,[8][9][10][11] partly due to the fact[12] that, in the Western world, Iran was known as "Persia".

On the Nowruz of 1935, Reza Shah Pahlavi asked foreign delegates to use the term Iran, the endonym of the country used since the Sasanian Empire, in formal correspondence.

[16] The Collins English Dictionary uses a variety of similar and overlapping definitions for the terms "Persian" and "Iranian".

[30][31] Iran is a primarily Shia Muslim country with Jewish, Baháʼí, Christian and Zoroastrian communities, a fact reflected in the migrant population in the UK.