British and American spelling differences

Here are the main ways in which British and American spelling are different.

Words ending in –re

British English words that end in -re often end in -er in American English:

British	US
centre	center
fibre	fiber
litre	liter
theatre	theater or theatre

Words ending in -our

British English words ending in -our usually end in -or in American English:

British	US
colour	color
flavour	flavor
humour	humor
labour	labor
neighbour	neighbor

Words ending in -ize or -ise

Verbs in British English that can be spelled with either -ize or -ise at the end are always spelled with -ize at the end in American English:

British	US
apologize or apologise	apologize
organize or organise	organize
recognize or recognise	recognize

Words ending in -yse

Verbs in British English that end in -yse are always spelled -yze in American English:

British	US
analyse	analyze
breathalyse	breathalyze
paralyse	paralyze

Words ending in a vowel plus l

In British spelling, verbs ending in a vowel plus l double the l when adding endings that begin with a vowel. In American English, the lis not doubled:

British	US
travel	travel
travelled	traveled
travelling	traveling
traveller	traveler

fuel	fuel
fuelled	fueled
fuelling	fueling

Words spelled with double vowels

British English words that are spelled with the double vowels ae or oe are just spelled with an e in American English:

British	US
leukaemia	leukemia
manoeuvre	maneuver
oestrogen	estrogen
paediatric	pediatric

 

Note that in American English, certain terms, such as archaeology, keep the ae spelling as standard, although the spelling with just the e(i.e. archeology) is usually acceptable as well.

Nouns ending with –ence

Some nouns that end with -ence in British English are spelled -ense in American English:

British	US
defence	defense
licence	license
offence	offense
pretence	pretense

Nouns ending with –ogue

Some nouns that end with -ogue in British English end with either -og or -oguein American English:

British	US
analogue	analog or analogue
catalogue	catalog or catalogue
dialogue	dialog or dialogue