A
- A cappella
- Adviser vs. advisor
- Aeon vs. eon
- Aeroplane vs. airplane
- Ageing vs. aging
- All together vs. altogether
- Aluminium vs. aluminum
- Ambiance vs. ambience
- Analyse vs. analyze
- Apologise vs. apologize
- Armor vs. armour
- Awhile vs. a while
- Ax vs. axe
B
- Barbed wire
- Behavior vs. behaviour
- Breath vs. breathe
- Brussels sprout
- Bus stop or busstop?
C
- Catalog vs. catalogue
- Center vs. centre
- Closed-minded
- Color vs. colour
- Colosseum and coliseum
- Cooperate vs. co-operate
- Cosy vs. cozy
- Counselor vs. counsellor
- Crier vs. cryer
D
- Decent vs. descent
- Defence vs. defense
- Dependant vs. dependent
- Derring-do
- Dike vs. dyke
- Dis vs. diss
- Disc vs. disk
- Dispatch vs. despatch
- Doughnut vs. donut
- Draft vs. draught
E
- E-mail vs. email
- Enclose vs. inclose
- Engrain vs. ingrain
- Enquire vs. inquire
- Envelop vs. envelope
- Envision vs. invision
- Envoi vs. envoy
- Exploitative vs. exploitive
F
- Favor vs. favour
- Favorite vs. favourite
- Feminity vs. femininity
- Fiber vs. fibre
- Fine-tooth comb or fine-toothed comb?
- Flavor vs. flavour
- Flier vs. flyer
- For god's sake
- Forty vs. fourty
- Forward vs. forwards
- Freshwater
G
- Gaol vs. jail
- Gaudy vs. gawdy
- Glamour vs. glamor
- Gray vs. grey
H
- Hara-kiri
- Harbor vs. harbour
- Harebrained
- Hark, harken, and hearken
- Hear, hear
- Heighth
- Highfalutin
- Humor vs. humour
I
- Ice tea or iced tea?
- Intact
J
- Jewelry vs. jewellery
K
- Ketchup, catsup, catchup
L
- Labor vs. labour
- Lasagna vs. lasagne
- Leaped vs. leapt
- Learned vs. learnt
- Licence vs. license
- Licorice vs. liquorice
- Linchpin vs. lynchpin
- Liter vs. litre
M
- Maneuver vs. manoeuvre
- Math vs. maths
- Mayonnaise vs. mayonaise
- Meager vs. meagre
- Metaphoric vs. metaphorical
- Meter vs. metre
- Mic vs. mike
- Midriff
- Minuscule, miniscule
- Mold vs. mould
- Mustache, moustache, and mustachio
- Muumuu
N
- Neandertal vs. neanderthal
- Neighbor vs. neighbour
O
- Ocher vs. ochre
- Odor vs. odour
- Offence vs. offense
- OK vs. okay
- Omelet vs. omelette
- One-time vs. onetime
- Oneself vs. one's self
- Opossum vs. possum
- Organise vs. organize
P
- Pajamas vs. pyjamas
- Paralyse vs. paralyze
- Peal vs. peel
- Percent vs. per cent
- Playwright or playwrite?
- Plough vs. plow
- Pompom, pompon, and pom-pom
- Practice vs. practise
- Pray vs. prey
- Pretence vs. pretense
- Preventative vs. preventive
- Program vs. programme
R
- Racket vs. racquet
- Re-create vs. recreate
- Realise vs. realize
- Remunerate vs. renumerate
- Restaurateur
- Rock 'n' roll, rock and roll, rock'n'roll, etc.
- Rogue vs. rouge
- Rumor vs. rumour
S
- Saccharin vs. saccharine
- Sacrilege, sacrilegious
- Saltwater vs. salt water
- Savanna vs. savannah
- Savior vs. saviour
- Sceptic vs. skeptic
- Sherbet vs. sherbert
- Shoo-in
- Skilful vs. skillful
- Smelled vs. smelt
- Somber vs. sombre
- Somersault
- Soup up
- Specter vs. spectre
- Spelled vs. spelt
- Spoiled vs. spoilt
- Stained glass or stain glass?
- Storey vs. story
- Straitjacket
- Subtle vs. subtil
- Supposed to
T
- T-shirt, t-shirt, tee-shirt, and tee shirt
- Theater vs. theatre
- Through vs. thru
- Tidbit vs. titbit
- Timeout vs. time out
- Tire vs. tyre
- Ton vs. tonne
- Toward vs. towards
- Treasurys
U
- Underway vs. under way
V
- Vicious vs. viscous
- Voicemail
W
- Wack vs. whack
- Wagon vs. waggon
- Web site or website?
- Wilful vs. willful
- Wreath vs. wreathe
- Write-off vs. write off
Y
- Yogurt vs. yoghurt