UK or US English: how to choose, and the differences that matter
Spelling, punctuation and date conventions side by side, and which variant to use when.
Readers notice when a document mixes the two. Pick one variant at the start and keep to it.
Which should I use?
- Follow your audience. A UK university, publisher or client usually expects UK English; a US one, US English.
- Follow the rules you are given. Journals and publishers state their preference in their author guidelines.
- International audience? Either is fine. Consistency matters more than the choice.
Spelling
| Pattern | UK English | US English |
|---|---|---|
| -our / -or | colour, favour, behaviour | color, favor, behavior |
| -re / -er | centre, theatre, metre | center, theater, meter |
| -ise / -ize | organise (or organize) | organize |
| -yse / -yze | analyse, paralyse | analyze, paralyze |
| Double l | travelled, cancelled, modelling | traveled, canceled, modeling |
| -ence / -ense | defence, licence (noun) | defense, license |
| -ogue / -og | catalogue, dialogue | catalog, dialogue |
Oxford spelling is a UK style that uses -ize (organize) but keeps other UK spellings. Some publishers and universities prefer it.
Punctuation and dates
UK English
- Quotation marks
- usually single: 'like this'
- Full stop with quotes
- outside unless part of the quote
- Abbreviations
- Mr, Dr, eg
- Dates
- 5 November 2026
US English
- Quotation marks
- usually double: "like this"
- Full stop with quotes
- inside: "like this."
- Abbreviations
- Mr., Dr., e.g.
- Dates
- November 5, 2026
Words that change meaning
| Word | UK meaning | US meaning |
|---|---|---|
| pants | underwear | trousers |
| first floor | one floor above the ground | the ground floor |
| quite | fairly ("quite good" = fairly good) | very ("quite good" = very good) |
What should never change
Quotations, official names (an organisation's name or a book title) and published references keep their original spelling, whichever variant you choose.
When you order an edit from us, you choose the variant and your editor works to it throughout. Tell us about any house style, such as Oxford spelling.
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