American	British	Notes
Aluminum *	Aluminium	.
Analog	Analogue	.
Anesthesia	Anaesthesia	.
Archeology	Archaeology	.
Boro	Borough	"Boro" Is Informal And Is Sometimes Seen In British Road Markings. In Scotland The Word Is "Burgh" But It Is Pronounced "Burr" Or, Sometimes, "Borough" NOT "Berg".
Bylaw	Bye Law	.
Catalog	Catalogue	.
Center	Centre	Also Meter & Metre, Theater & Theatre etc.
Color	Colour	Also Favor & Favour, Neighbor & Neighbour etc.
Curb	Kerb	Edge Of Roadway Or Pavement. "Curb" In The Sense Of "Restrain" Is Used In British And American English.
Defense	Defence	.
Dialog	Dialogue	.
Donut	Doughnut	"Donut" Is Informal And Is Quite Commonly Used In BE To Suggest That The Bun Is Of A Typical American Character.
Draft	Draught	.
Encyclopedia	Encyclopaedia	.
Fetus	Foetus	.
Favorite	Favourite	.
Gage	Gauge +	American Usage May Be Obsolete.
Groin	Groyne	Sea Defence.
Gray	Grey	.
Gynecology	Gynaecology	.
Hauler	Haulier	.
Honor	Honour	.
Humor	Humour	However Humorous Is Spelt As Such In Both Languages.
Jewelry	Jewellery	.
License	Licence	British Usage Is License For The Verb And Licence For The Noun
Maneuver	Manoeuvre	.
Meter	Metre	British Usage Is "Meter" For A Measuring Device And "metre" For The Unit Of Length
Mold	Mould	.
Mustache	Moustache	.
Nite	Night	"Nite" Is Informal In Both AE And BE
Omelet	Omelette	.
Pajamas US	Pyjamas	.
Practice	Practise	British Usage Is "Practise" For The Verb And "Practice" For The Noun
Program	Programme	British Usage Is "Program" For Computers And "Programme" For Television Or Radio
Raise	Rise	When Talking About Pay Increases.
Realize	Realise	Also Dramatize & Dramatise, Industrialize & Industrialise etc.
Routing	Routeing	.
Specialty	Speciality	.
Story	Storey	Of Building
Sulfur	Sulphur +	According To A Correspondent The American Spelling Is Now "Official" British Spelling For Use By Professional Chemists But It Is Unlikely To Be Recognised By Any British English Speaker
Traveling	Travelling	Also Targeting & Targetting, Paneling & Panelling.
Thru	Through +	American Usage Is Obsolescent But May Still Be Seen On Road Signs Etc
Tire	Tyre	Part Of Wheel In Contact With Road
Vise	Vice	Tool

• * Many American Usage's Are Familiar To British English Speakers. This Asterisk Indicates American Usage's That Are Comparatively Unfamiliar Or Unknown
• obs These Are American Usage's That Are, According To Correspondents, Obsolete Or Obsolescent. American English Speakers Now Use The Same Words As British English Speakers
• Can These Usage's Are, I Believe, Confined To Canada. In General Canadian English Is More Similar To American English Than British English. Where Canadian Usage Is The Same As British Usage As Distinct From American Usage This Is Indicated.
• US These Usage's Are Confined To The USA And Are Not Known In Canada Or The UK
• ? I'm Not Certain About The Meaning Of The American Usage

 

Generally AE -or As A Word Ending Is Equivalent To -our In BE, American -er As A Word Ending Is Sometimes Equivalent To -re In BE.

In AE The Final 'E' Is Removed From Verbs Before Adding -ing, In Correct BE This Is Not Done Giving "Routeing" (British) And "Routing" (American), However The American Practice Of Dropping The "e" Is Becoming Quite Common In British English.

If A Verb Ends In A Single 'L' Then The American -ing, -ed And -er Forms Also Have A Single 'L' Whereas The British Forms Have A Double 'LL'. For Example American English Has Signaler, Signaling And Signaled Whereas BE Has Signaller, Signalling And Signalled. The Same Applies for Verbs Ending In 'T' Such As Targetting In BE And Targeting In AE.

AE Tends To Prefer -ize And -ization Whereas BE Prefers -ise And -isation. Canadian Spelling Seems To Be Intermediate Between The BE And AE Forms But Is Generally Closer To British Practice.

When Spelling Out Words (And 'Phone Numbers) It Is British Practice To Say Things Such As "Double E" For "EE" And "Treble 3" For "333".

BE The Phrase Would Be "Not Much Further" In AE "Not Much Farther" Would Be Used. This Is Relatively Unknown In BE.

There Are, Of Course, Exceptions To The Above Rules. American Usage Is "Glamour" Not "Glamor" And "Advertising" Not "Advertizing". BE Has "Honorary" And "Honorific" Without The 'U'. Several Correspondents Have Also Noted That The British Usage's "Centre" And "Theatre" Are Displacing The American Usage's, Particularly Where The Establishment In Question Wants To Suggest That It Is Of Superior Quality.

Please Note That "Tonne" Is Not A British Spelling Of "Ton" But A Quite Separate Metric Unit Equal To 1000 Kg As Distinct From The British Ton Of 2240 Lb. (= 1016.96 Kg).