Received Pronunciation is the accent most non-British people mean when they say “a British accent”. It is spoken by around 2% of the population, it is not the accent of any particular place, and it is in visible retreat.
What “received” means
The older sense of received — accepted, approved, as in “received wisdom”. The term was popularised by the phonetician Daniel Jones in the 1920s to describe the pronunciation “received” in educated society.
Its defining feature is that it carries no regional information. Every other British accent tells you roughly where someone grew up; RP tells you only how they were educated. It spread through the public schools, Oxford and Cambridge, the officer class and the civil service, and it was deliberately taught.
BBC English
The BBC adopted RP as its broadcasting standard from the 1920s, and for decades announcers were required to use it — reportedly including wearing dinner jackets to read the evening news on radio, which nobody could see.
That has entirely gone. The BBC now actively recruits regional voices, and its main news and sport presenters speak with Scottish, Welsh, Northern, Midlands and London accents. The change was resisted noisily at the time by letter-writing viewers and is now unremarkable.
How it is changing
RP itself has shifted considerably. The clipped 1950s newsreel version — heard in wartime broadcasts and old films — sounds absurd to modern ears, and even the Royal Family’s speech has moved. Linguists analysing decades of Elizabeth II’s Christmas broadcasts found her vowels drifted measurably towards mainstream southern English over her reign.
Younger upper-class speakers now often use a softened version, and many have adopted features of Estuary English — glottal stops, and some London vowels — in a way their grandparents would have found unthinkable.
The stigma reversal
For most of the twentieth century, a regional accent was something to lose in order to get on. That pressure has weakened sharply, and in some contexts reversed — an RP accent can now read as posh, remote or out of touch, and public figures have been caught trying to sound less like themselves rather than more.
Accent bias has not disappeared. Studies still find measurable disadvantage attached to certain accents in hiring and in perceived competence, particularly Birmingham, Liverpool and Essex. But the assumption that RP is the correct form of English and everything else a deviation is genuinely dead.
Where it survives
Classical theatre, some of the law, older broadcasting archives, the Royal Family, and a certain kind of independent school. It is also, for reasons of long-standing casting habit, the accent Hollywood gives to villains, aristocrats and anyone Roman.
The other names
“The Queen’s English” and “the King’s English” are used loosely to mean both RP and correct standard English, which are separate things — you can speak perfect standard English in a Glasgow accent. “Oxford English” and “BBC English” are similarly imprecise. Linguists use RP, and increasingly qualify it as “Standard Southern British English”, since even the name is now considered a bit dated.