The article analyzes the language ideology of the United Kingdom at the present stage and its language policy in the field of control over the use of English and measures to support its study by immigrants and their children. Despite the fact that English is the single state language of Great Britain and the most common world language, as a result of the collapse of the British colonial empire and global migration processes, its dominance in the kingdom's territory is weakened due to increased communitarianism and the refusal of immigrants to integrate into British society. The relations of language and citizenship in modern national states are studied in terms of strengthening national unity, which requires that the national language perform the functions of a high language in the diglossia system or at least be present in the system of societal bilingualism. The achievement by the state of the goals of language policy is due to the socio-political and economic situation, which usually does not fall within the sphere of interest of sociolinguists, but whose influence on the language situation is stronger than the results of the language policy itself. Language questions appearing in population censuses in the United Kingdom are of broader socio-economic importance. Thus, for the first time in the history of censuses, a link was established between the level of proficiency in English and the state of health of the immigrant population: young immigrants who passed through the British education system have a better state of health than their older relatives, who speak English poorly. In addition, it has been established that all immigrant communities whose members declare good knowledge of English come from countries where it is either an official language or is compulsory taught in schools from a very young age.