Fortnight is very common in UK English, Australian English and New Zealand English. So, most of the Anglophone 'five-eyes'.
I would expect that it's also common in Canadian English, but seeing that the US is just over the border and 'fortnight' is uncommon in the US, maybe not.
"Britain and the US are separated by a common language." - Winston Churchill
I would expect that it's also common in Canadian English, but seeing that the US is just over the border and 'fortnight' is uncommon in the US, maybe not.
"Britain and the US are separated by a common language." - Winston Churchill