Received Pronunciation and Estuary English are two accents of British English. Received Pronunciation is the variety of British English which is usually taught to foreigners. It has other names such as BBC English, Queen's English and Oxford English. Estuary English is a variety of English spoken in southeastern England. Though similar, they have differences in pronunciation.
In Estuary English, a word-final l vocalizes and is realized as a w. This happens in words such as apple, ball and well. This is not the case in Received Pronunciation.
Another difference concerns the glottal stop. In Received Pronunciation, it can occur in combination with an alveolar plosive. An example is the word football. However, in Estuary English, the glottal stop can replace another consonant. It is thus possible to pronounce football with a glottal stop instead of an alveolar plosive. The glottal stop can also replace other plosives in Estuary English. Examples include bookshelf and laptop. Notice that the glottal stop occurs syllable-finally.
Also different in the two varieties is the phenomenon of h-dropping. In Received Pronuncation it never occurs, but in Estuary English pronouns such as he and him and the auxiliary have can be pronounced without the h. H-dropping is possible with such words in Estuary English, but not in Received Pronunciation.
Though they are similar varieties of English, Received Pronunciation and Estuary English have pronunciation differences. Estuary English has vocalization of the alveolar lateral, more extensive use of the glottal stop and h-dropping in certain situations. These pronunciation differences serve to distinguish Received Pronunciation from Estuary English.