British vs American spelling is the set of systematic differences between the way many words are written in the United Kingdom and the way they are written in the United States. The split is not random. Most of it goes back to Noah Webster, who simplified a group of British spellings in the early nineteenth century, and to habits that grew after that. Once you know the patterns, colour/color, centre/center and travelling/traveling stop looking like isolated tricks.
This guide covers the twelve differences spellers meet most often and notes which form U.S. school bees expect. For the doubling pattern that sits underneath traveling and travelling, see the double consonant rule.
Why British and American spelling diverged
For a long time, English spelling was messy on both sides of the Atlantic. Printers, authors and dictionaries did not always agree. In 1828, Noah Webster published An American Dictionary of the English Language and argued for simpler, more regular forms: -or instead of -our, -er instead of -re, and -se in words such as defense. Many of those choices became standard in the United States. British English kept more of the older French-influenced spellings.
Neither set is more logical in every case. Color is shorter; centre keeps the word closer to French centre. What matters for a speller is consistency: pick the variety your contest, teacher or publication uses, and learn the patterns rather than a giant unmatched list.
U.S. classroom bees and the Scripps National Spelling Bee use American dictionary spellings. If you read British novels, news or textbooks, you will still see the other forms. Treat them as a second system, not as mistakes.
1. -our and -or
This is the difference people notice first.
| British | American | Examples |
|---|---|---|
| -our | -or | colour/color, favour/favor, honour/honor, labour/labor, neighbour/neighbor, rumour/rumor, flavour/flavor, behaviour/behavior |
The pattern holds for related words: favourite/favorite, honourable/honorable. A few words never took -our in either variety (error, terror, anterior), so do not add a u just because the word feels formal.
In a U.S. bee, spell color, favorite and neighbor.
2. -re and -er
British English keeps -re in many words that came through French. American English reverses the letters to -er.
| British | American |
|---|---|
| centre | center |
| fibre | fiber |
| litre | liter |
| metre | meter |
| theatre | theater |
| sombre | somber |
Meter in American English is both the measuring device and the spelling of the metric unit. British English uses metre for the unit and meter for many measuring devices, so that pair is easy to mix up if you read both varieties.
Words such as acre, ogre and massacre keep -re in American English too. Learn those as exceptions instead of forcing every -re word into -er.
3. -ise and -ize
Many verbs can end in -ise or -ize: organise/organize, realise/realize, recognise/recognize. American English almost always uses -ize. British English accepts both, though -ise is very common in newspapers and schools. Oxford spelling, used in some British academic books, prefers -ize because the ending comes from Greek -izein.
Related nouns follow the verb: organisation/organization, realisation/realization.
A smaller group is not a free choice even in Britain. Advertise, surprise, revise and supervise keep -ise in both varieties because they do not come from the Greek -izein pattern. Do not write advertize in a U.S. bee just to make the set look regular; American dictionaries still use advertise.
4. Doubled consonants: travelling or traveling
This is where British vs American spelling meets the doubling rule.
On one-syllable words, both varieties double the same way: running, stopped, bigger. On many two-syllable words with stress on the first syllable, British English doubles a final l and American English usually does not:
| Base | American | British |
|---|---|---|
| travel | traveling, traveled, traveler | travelling, travelled, traveller |
| cancel | canceling, canceled | cancelling, cancelled |
| label | labeling, labeled | labelling, labelled |
| fuel | fueling, fueled | fuelling, fuelled |
| worship | worshiping, worshiped | worshipping, worshipped |
Stressed endings stay doubled in both: preferred, beginning, controlled. The split is about unstressed -el, -al and a few similar endings, not about the 1-1-1 rule itself.
5. -ce and -se
A small set of nouns and verbs swap c and s:
- British defence, offence, licence (noun) versus American defense, offense, license (noun and verb)
- British practise (verb) and practice (noun) versus American practice for both
- British pretence versus American pretense
Advice (noun) and advise (verb) keep the c/s contrast in both varieties. That pair is older than Webster and did not split.
6. ae and oe
British English often keeps the ligature-style vowel pairs ae and oe in words from Greek and Latin. American English usually simplifies them to e:
| British | American |
|---|---|
| paediatric | pediatric |
| anaesthesia | anesthesia |
| haemoglobin | hemoglobin |
| oestrogen | estrogen |
| diarrhoea | diarrhea |
| manoeuvre | maneuver |
Scientific and medical vocabulary is full of these. They are high-value for school bees because the American forms look shorter than the British book forms many students have seen. Our guide to Greek and Latin root words explains the roots; this page explains which vowels American spelling dropped.
Some words keep the extra vowel even in American English, such as aesthetic (also spelled esthetic, though aesthetic is still common in the U.S.). Check a current American dictionary when you are unsure.
7. Grey or gray, towards or toward
A handful of everyday words simply chose different standard forms:
- grey (British) / gray (American)
- towards (more common in Britain) / toward (more common in the U.S.)
- afterwards / afterward
- amongst / among (among is standard in American prose)
- whilst / while
These are style choices as much as spelling choices. For a U.S. bee, study gray and toward.
8. Programme, cheque and storey
A few pairs look unrelated until you see them together:
| British | American | Notes |
|---|---|---|
| programme | program | American program covers both computer programs and events; British English often keeps programme for events and broadcasts and uses program for computers |
| cheque | check | The banking slip is cheque in Britain; American English uses check for that and for the verb |
| storey | story | A floor of a building is a storey in Britain and a story in the U.S. |
| tyre | tire | The wheel covering |
| kerb | curb | The edge of a pavement/sidewalk; American curb is also the verb “to restrain” |
| pyjamas | pajamas | Night clothes |
| aluminium | aluminum | The metal; the vowel count is different, not just one letter |
| maths | math | This is vocabulary more than spelling, but it appears on the same lists |
Aluminum versus aluminium is a useful reminder that a “British vs American” pair can change the number of syllables. Ask for the definition if a pronouncer’s word could be either.
9. -ogue and -og
British English often keeps -ogue: catalogue, dialogue, analogue. American English commonly shortens these to catalog, dialog and analog, though the longer forms still appear in American writing, especially dialogue. For school lists, expect the shorter American form unless your dictionary lists both as equal.
10. Past tense of some verbs: learnt or learned
Both varieties use regular past tenses such as played and worked. British English more often keeps irregular-looking -t forms that American English has mostly regularized:
- learnt / learned
- dreamt / dreamed
- leapt / leaped
- spelt / spelled
- burnt / burned
American dictionaries usually prefer learned, dreamed, leaped and spelled. Burned and burnt both appear in the U.S., with burnt more common as an adjective (burnt toast).
11. Doubled vowels and extra letters in a few holdouts
Beyond the big patterns, a short list of holdouts is worth memorizing because they do not fit neatly in one row of a table:
- ageing (British, also accepted) / aging (American usual form)
- acknowledgement (both, very common in Britain) / acknowledgment (preferred American)
- judgement (common British, especially outside legal writing) / judgment (preferred American)
- fulfil / fulfill, skilful / skillful, enrol / enroll
That last group is another doubled-letter split. American English adds an extra l in fulfill, skillful and enroll. British English usually does not.
If one of these keeps appearing in your error log, add it to your commonly misspelled words list rather than forcing it into a pattern that does not quite fit.
12. How to study the differences for a bee
Do not try to memorize every pair in a world dictionary. Study by family:
- Make one column of -our words and rewrite them as -or.
- Do the same for -re/-er and ae/oe.
- Drill the l-doubling set (travel, cancel, label) against the stressed set that both varieties double (prefer, begin, control).
- Write defense, license, practice, gray, toward, program, check, story, tire and aluminum until they feel automatic.
- When you read a British book, notice the form instead of copying it into your bee notebook.
Language of origin still helps for roots, prefixes and silent letters, which is why pages such as silent letter words and French words in English belong in the same study pile. It will not tell you whether to write color or colour. That choice is about variety, not etymology.
If you are building a wider plan, pair this page with how to prepare for a spelling bee and with daily practice on the Spelling Bee Hub home page.
Frequently Asked Questions
What is the difference between British and American spelling?
They are two standard ways of writing many of the same English words. Common splits include colour/color, centre/center, travelling/traveling and defence/defense. The differences follow patterns, most of them dating to Noah Webster’s American dictionary work.
Is color or colour correct?
Both are correct in their own variety. Colour is the usual British spelling. Color is the usual American spelling and the form U.S. school bees expect.
Why do American and British spellings differ?
Noah Webster pushed simpler American forms in the early 1800s, and U.S. usage settled on many of them. British English kept more older, often French-influenced spellings such as -our and -re.
Do spelling bees use British or American spelling?
U.S. classroom bees and the Scripps National Spelling Bee use American dictionary spellings. If a word has two standard forms, study the American one for those contests.
Is traveling spelled with one l or two?
American English usually writes traveling. British English usually writes travelling. Both follow regular rules inside their own system.
Should I learn both British and American spelling?
Learn one set thoroughly for tests and bees, then learn the patterns of the other so British books do not pull you off your American forms. Pattern study is faster than memorizing two complete lists.