Jamaican English, including Jamaican Standard English, is the variety of English native to Jamaica and is the official language of the country. A distinction exists between Jamaican English and Jamaican Patois (a creole language), though not entirely a sharp distinction so much as a gradual continuum between two extremes. Jamaican English tends to follow British English spelling conventions.

There are several language varieties that have significantly impacted the Jamaican dialect of English. English was introduced into Jamaica in 1655, because of British colonisation. British English was spread through post-primary education, and through British teachers that immigrated to Jamaica. Standard English in Jamaica conflated with the British standard. Individuals who speak the standard variety are often considered to be of a higher social class; the people who speak more standard English than patois are known as “uptown” Also, American English has contributed to the Jamaican English dialect. These impacts can be traced to the development of stronger social and economic ties with the United States,^[when?] the popularity of U.S. cultural offerings, including film, music, and televised dramas and comedies and tourism. Jamaican Patois is another source of influence on Jamaican English. Many rural homes are monolingually Patois.

There are great similarities between standard British English and the standard variety of Jamaican English, including in grammar, idiom, and vocabulary.

Features of standard Jamaican English include the characteristic pronunciation of the /aʊ/ diphthong in words like MOUTH, which is often more closed and rounded [ɵʊ] than in British Received Pronunciation (RP) or General American (GA); the pronunciation of the STRUT vowel /ʌ/ to [ɵ~o] (again, more closed and rounded than the RP or GA varieties); and the very distinctive feature of "variable semi-rhoticity". Non-rhoticity (the pronunciation of "r" nowhere except before vowels) is highly variable in Jamaican English and can depend upon the phonemic and even social context. Jamaican English accents are: non-rhotic regarding words of the LETTER lexical set (at the ends of unstressed syllables); rhotic (i.e., fully preserving the "r" sound) regarding words of the NEAR and FORCE sets; high to middling in degrees of rhoticity regarding the SQUARE, NURSE, and CURE sets; and low regarding rhoticity with most other word sets. When "r" is followed by a consonant, non-rhoticity is more likely than when "r" is not followed by a consonant. However, overall more rhoticity is positively correlated with higher levels of education. This has been attributed to the Jamaican education system normalising and promoting a rhotic variety of English. Thus, the overall degree of rhoticity in educated Jamaican English remains very low, with rhoticity occurring 21.7% of the time.

Merger of the diphthongs in "fair" and "fear" takes place both in Jamaican Standard English and Jamaican Patois, resulting in those two words (and many others, like "bear" and "beer") often becoming homophones: the sound being [eːɹ], though often [iɛɹ] (something like "ee-air"; thus "bear/beer" as "bee-air").

The short "a" sound (TRAP, man, hat, etc.) is very open [a], similar to its Irish variants, while BATH, PALM, and START all use this same sound too, but lengthened, and perhaps slightly backed; this distinction can maintain a London-like TRAP–BATH split. Both LOT/CLOTH and THOUGHT use a rounded [ɔ], though a cot-caught merger is theoretically avoided by the latter set of words being more lengthened; however, in reality, a full merger (of LOT/CLOTH/THOUGHT) is reportedly increasing in informal contexts. For Jamaican Patois speakers, the merged vowel is much lower. GOAT and FACE vowels in the standard educated dialect are long monophthongs: respectively [oː] and [eː]. The unstressed schwa phoneme (COMMA) appears to be normally produced in the area of [a~ɐ].

Before the low central vowel [a], the velars [k] and [ɡ] can be realized with palatalisation, so that cat can be pronounced [k^hat ~ kjat] and card as [k^ha:d ~ kja:d]); while [ɡ] and [ɡj] coexist, as in gap [ɡap ~ ɡjap] or guard [ɡa:(ɹ)d ~ ɡja:(ɹ)d]. These variations are distinct phonemes in Jamaican Patois before [a]: [ɡja:dn̩] is garden while [ɡa:dn̩] is Gordon; [kja:f] is calf while [ka:f] is cough. They are not distinct phonemes in Jamaica English because these word pairs are distinguished by the vowel ([a] vs [ɔ]) instead. However, this fact hasn't stopped educated speakers from incorporating [kj] in their English at least before unlengthened "a". However, vowel length can be a relevant factor, since it is possible to hear forms like [kjat] for cat, [kjaɹɪ] for carry, [kjaɹaktʌ] for character, and [kjaɹɪbiǝn] for Caribbean, but affluent or aspiring middle-class speakers tend to avoid [kja:ɹ] for car due to its longer vowel.

Presumably less-educated Jamaican Patois speakers may speak English with several other notable features, including a TRAP–LOT merger (e.g. with rat and rot homophones) to [ɔ] and a PRIZE–CHOICE merger (e.g. with line and loin homophones) to [ɔi]. Th-stopping is also common.