- Offence and offense are both correct.
- Offence is the spelling more commonly used outside of the United States.
- Offense is the spelling more commonly used in the United States.
Offense is spelled differently based on where you, or your audience, are. But neither offense nor offence are wrong.
Offence vs. Offense—Which Is Correct?
In one sense, offense means an attack. But it also means an affront or insult. Offense can also be spelled offence. The difference is that offense is the standard spelling in the United States, while offence is standard in other English-speaking countries:
The adjective derived from offense, offensive, is spelled with an s in American and British English alike. It doesn’t have a version that’s spelled with c:
It’s the same with the adverb offensively—it’s never spelled with a c:
Offensive in American Publications
Offence outside the US
And speaking of words spelled differently in American and British English, did you know that omelet (or omelette) is one of them? Catalog is another one—it can also be spelled catalogue. And benefitted can also be spelled with only one t—that’s how they do it in the United States.
from Grammarly Blog https://www.grammarly.com/blog/offence-offense/