08/09/2026
British vs American medical spelling in OET — the 6 patterns you need to know:
OET accepts BOTH variants. They don't penalise you for choosing British or American. They penalise you for MIXING them in the same letter.
Here are the 6 patterns that cover almost every difference:
1️⃣ -our vs -or
tumour / tumor, colour / color, behaviour / behavior
2️⃣ -ae- / -oe- vs -e- (this is the big one for medical terms)
anaemia / anemia, oedema / edema, paediatric / pediatric, haemorrhage / hemorrhage, oesophagus / esophagus
3️⃣ -ise vs -ize
hospitalise / hospitalize, specialise / specialize, stabilise / stabilize
4️⃣ -re vs -er
centre / center, litre / liter, fibre / fiber
5️⃣ -lled vs -led
cancelled / canceled, counselled / counseled, travelled / traveled
6️⃣ -ence vs -ense
defence / defense, licence / license
Quick tip: if you just learn patterns 1 and 2, you'll cover over 80% of the differences that actually appear in OET writing tasks.
Pick whichever variant you trained with, and stick with it the whole letter. Consistency is what examiners look for.
Which variant do you use? British or American? 👇