American English is the form of English used in the United States. It includes all English dialects used within the United States of America. British English is the form of English used in the United Kingdom. It includes all English dialects used within the United Kingdom. Differences between American and British English include pronunciation, grammar, vocabulary (lexis), spelling, punctuation, idioms, and formatting of dates and numbers.
Differences in use of tenses
In British English the present perfect is used to express an action that has occurred in the recent past that has an effect on the present moment. For example: I’ve misplaced my pen. Can you help me find it? In American English, the use of the past tense is also permissible:I misplaced my pen. Can you help me find it? In British English, however, using the past tense in this example would be considered incorrect.
Other differences involving the use of the present perfect in British English and simple past in American English include the words already, just and yet.
British English: I’ve just had food. Have you finished your homework yet?
American English: I just had food. OR I’ve just had food.
I’ve already seen that film. OR I already saw that film.
Differences in Vocabulary
While some words may mean something in British English, the same word might be something else in American English and vice versa. For example, Athlete in British English is one who participates in track and field events whereas Athlete in American English is one who participates in sports in general.
Rubber in British English: tool to erase pencil markings.
Rubber in American English: condom.
There are also some words like AC, Airplane, bro, catsup, cell phone etc. which are common in American English and not used very often in British English. Some words widely used in British English and seldom in American English are advert, anti clockwise, barrister, cat’s eye.
Differences in Spelling
There are many words that are spelt differently in both forms of English. Some examples are:
| American English spelling | British English spelling |
| color | colour |
| fulfill | fulfil |
| center | centre |
| analyze | analyse |
| aging | ageing |
| dialog | dialogue |
| anesthesia, | anaesthesia |
A majority of the spelling differences between American and British English fall into the following categories:
- Latin-derived spellings
- –our (British) and –or (American). e.g. colour vs color
- –re (British) and –er (American). e.g. centre vs center
- –ce (British) and –se (American). e.g. defence vs defense
- Greek-derived spellings
- –ise (British) and –ize (American). e.g. centralise vs centralize
- –yse (British) and –yze (American). e.g. analyse vs analyze
- –ogue (British) and –og (American). e.g. dialogue vs dialog
- Simplification of ae and oe in American English. e.g. gynaecology vs gynecology
Differences in the use of Prepositions
There are also a few differences between British and American English in the use of prepositions. For example: While the British would play in a team, Americans would play on a team. Another example: While the British would go out at the weekend, Americans would go out on the weekend.
Differences in Verb usage
American and British English may also use a base verb in different manners. For example: For the verb ” to dream”, Americans would use the past tense dreamed while the British would use dreamt in past tense. The same applies to “learned” and “learnt”. Another example of differing past tense spellings for verbs in American and British English is “forecast”. Americans use forecast while the British would say forecasted in simple past tense.
Differences in Pronunciation
Some words that are pronounced differently in American vs British English are controversy, leisure, schedule etc. There are also some words like Ax (Axe in British) and Defense (Defence in British) which have the same pronunciation but different spellings in both languages.
Time telling in British vs American English
Both languages have a slightly different structure of telling the time. While the British would say quarter past ten to denote 10:15, it is not uncommon in America to say quarter after or even a quarter after ten.
Thirty minutes after the hour is commonly called half past in both languages. Americans always write digital times with a colon, thus 6:00, whereas Britons often use a point, 6.00.
Differences in Punctuation
While the British would write Mr, Mrs, Dr, the Americans would write Mr., Mrs., Dr.
