American vs British English: Key Differences

Write "colour" and an American reader may think it's a typo. Write "color" and a British editor might reach for the red pen. Neither is wrong, but they are different, and it pays to know which one you're meant to be using.

I'm a British writer, so I've leaned on Wikipedia's detailed comparison pages for the facts here and kept to the main patterns that catch people out. It's a quick guide, not a full style manual.

Why two spelling systems exist

Wikipedia explains that Noah Webster's 1828 American Dictionary helped establish American spelling standards. It also says he didn't invent these spellings, he chose between options that already existed. The British standard followed Samuel Johnson's dictionary of 1755.

Spelling patterns that differ between American and British English

Pattern	British	American
-our / -or	colour, honour, favour	color, honor, favor
-re / -er	centre, metre, theatre	center, meter, theater
-ise / -ize	organise, recognise	organize, recognize
-yse / -yze	analyse, paralyse	analyze, paralyze
Doubled l	travelled, cancelled, labelled	traveled, canceled, labeled

Wikipedia notes plenty of exceptions. Verbs such as advise and surprise take -s- everywhere, and a few words like acre are spelled the same in both.

Licence, practice and other -ce / -se words

In British English, some words keep a noun and verb split: licence (noun) and license (verb), practice (noun) and practise (verb). American English uses license and practice for both. British English also writes defence where American English writes defense.

Different words for the same thing

Vocabulary trips people up more than spelling. Wikipedia lists pairs such as:

• lorry and truck
• petrol and gas
• pavement and sidewalk
• lift and elevator
• aubergine and eggplant
• trousers and pants
• bonnet and hood, boot and trunk
• maths and math

Some words mean different things. Football means association football in the UK and American football in the US. Pants means trousers in the US but underwear in the UK. Table means to open a topic for discussion in the UK, but to postpone it in the US.

Grammar and phrasing differences

• Collective nouns: In the US a committee usually takes a singular verb. In the UK it can take a singular or plural verb depending on whether you mean the group as a whole or its members.
• Days of the week: Americans can drop "on" ("won the game Sunday"), while British writers usually keep it.
• Queues: Americans wait in line, the British wait in the queue.
• Studying: The British revise for an exam, Americans review for one.

Words that cause confusion in business writing

In day-to-day business writing, a few differences crop up more than most. Wikipedia's list of vocabulary pairs is long, but these are the ones I'd double-check before sending anything to an audience in another country.

• Post and mail: a British reader posts a letter, while an American mails it.
• Maths and math: British English shortens mathematics to maths, American English to math.
• Aluminium and aluminum: the same metal, spelled two ways.
• Public school: in England this means a fee-paying private school, while in the US it means a state-run school.
• Table: to table a topic means to start discussing it in the UK, but to postpone it in the US.

That last one is the sort of difference that can cause real confusion in a meeting or an email, because the same sentence can mean opposite things to two readers. When in doubt, choose a plainer word that works in both.

Spelling differences inside the same country group

It's also worth knowing that British and American English aren't the only options. Wikipedia notes that South Africa, Australia and New Zealand prefer -yse in words like analyse, while Canada now generally prefers -yze. If your readers are mainly in one of those countries, check which convention they use before assuming either.

Punctuation and small style habits

Beyond spelling, the two varieties have different habits that show up in everyday writing. The quickest way to avoid mixing them is to decide on one set of conventions before you start and write them in a short note for anyone else who contributes.

• Pick one spelling set and apply it to headings, captions, image text and buttons, not just the body copy.
• Run your spell checker with the right language setting selected, but read through afterwards because it won't catch vocabulary differences.
• Watch for words that look the same but mean different things, like football or pants.
• Keep quoted material as the original writer spelled it.

Spelling check: a short list to keep handy

Word you might write	British	American
Hue and shade	colour	color
A place in the middle	centre	center
To arrange	organise	organize
To examine	analyse	analyze
To go on a journey	travelled	traveled
Official permission (noun)	licence	license
Protection from attack	defence	defense

If you keep this short list nearby, you'll catch most of the slips that give away a mixed-up document.

Which English should you use?

Choose the version your reader expects, and then stay consistent. A UK audience will notice American spellings, and a US audience will notice British ones. If you're writing for a publication, check its style guide or recent articles first. Wikipedia also notes that Canada generally prefers -ize and Australia, New Zealand, Ireland and India prefer -ise, so "British or American" isn't always the full picture.

This matters when you're pitching too. A tidy, correctly spelled email makes a better first impression, which I cover in my guide on how to write a pitch email.

Writing for an American audience

If you're a British writer or business owner aiming at US readers, switching spellings and vocabulary is a good first step, and choosing the right publications comes next.

If you're writing for an American audience, here are US sites that accept contributor articles.

Frequently asked questions

What is the main difference between American and British English?

Spelling and vocabulary are the most noticeable. British English uses -our, -re and often -ise, while American English uses -or, -er and -ize, and many everyday words differ.

Is it colour or color?

Colour is the British spelling and color is the American one. Both are correct for their audience.

Is -ise or -ize correct in British English?

Most British writing uses -ise, but Wikipedia notes that Oxford University Press style uses -ize. Pick one and stay consistent.

Do Australians use British or American spelling?

Wikipedia says Australia, New Zealand, Ireland and India generally prefer -ise, as in British English, while Canada generally prefers -ize.

Which should I use on my website?

Use the one your main readers expect, and apply it throughout. Check a publication's style guide if you're writing for someone else.