• 3-minute read
  • 29th March 2016

Colour or Color? British and American Spelling

George Bernard Shaw once remarked that ‘England and America are two countries separated by a common language’. However, as well as ignoring the Atlantic Ocean, Shaw’s proclamation overlooks the many differences between British and American spelling.

Here though, we’ll look at the systematic ways in which British and American English diverge, as you’ll need to know these if writing for an international audience.

-our vs. -or

Words we spell with an ‘-our’ in the UK are often simplified in American English, which tends to drop the ‘u’.

UK Spelling

US Spelling

Humour

Humor

Colour

Color

Favourite

Favorite

-re vs. -er

When an English word ends in ‘-re’, American English reverses this to make the spelling consistent with other English words that end with an ‘-er’ sound.

UK Spelling

US Spelling

Centre

Center

Theatre

Theater

Manoeuvre

Maneuver

-ae/-oe/-oeu vs. -a/-o/-eu

As with ‘manoeuvre/maneuver’ in the table above, American English also simplifies vowel combinations in some words.

UK Spelling

US Spelling

Paediatric

Pediatric

Oestrogen

Estrogen

Manoeuvre

Maneuver

-se vs. -ze

One of the most common spelling differences between UK and US English is that many American words take a ‘z’ where the British versions can use either ‘s’ or ‘z’.

UK Spelling

US Spelling

Organise/Organize

Organize

Recognise/Recognise

Recognize

Apologise/Apologize

Apologize

These variations also apply to modifications of these words, so British English accepts both ‘organisation’ and ‘organization’, while American English only uses ‘organization’.

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Some people claim that using a ‘z’ in these words is only acceptable in American English, but either version is fine as long as you apply consistent spelling throughout.

The one significant exception is when the word is spelled with a ‘-yse’, such as ‘catalyse’ and ‘analyse’; these terms can only be spelt with an ‘s’ in British English, but always take a ‘z’ in American English (e.g. ‘analyze’ and ‘catalyze’).

-ogue vs. -og

Another simplification, as American spellings lose the ‘-ue’ from words that end in ‘-ogue’.

UK Spelling

US Spelling

Dialogue

Dialog

Analogue

Analog

Catalogue

Catalog

-ence vs. -ense

Many words spelled with a soft ‘c’ in British English take an ‘s’ in American English.

UK Spelling

US Spelling

Defence

Defense

Offence

Offense

Pretence

Pretense

However, it’s worth noting that the adjectival forms of these words are spelled with an ‘s’ in both UK and US English (e.g. ‘defensive’, ‘offensive’).

Keep in mind, too, that UK terms which differ in spelling when used as either a noun or an adjective (e.g. ‘practice/practise’) often use a single spelling for both forms in US English (so ‘practice’ is both the noun and verb in America).

Comments (3)
Daniel Vissing Dalsgaard
13th March 2019 at 06:24
THANK YOU!! Color and colour was making me crazy.
    lucy
    22nd September 2019 at 10:36
    sameeeee
Sonusketches
2nd June 2019 at 16:32
I learned more from here thank you




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