On accident vs by accident

I've noticed that it's becoming very common among the younger generation in the states to use 'on accident' instead of 'by accident'.

Is 'on accident' considered grammatically correct?

How common is this phrase used in the UK and Australia?

Thanks in advance.

On is incorrect

"On accident" is an ignorant and careless way of saying "by accident". It was formed by analogy with its antonym, "on purpose".

Either one sounds fine. Although I prefer by accident.

I agree with L.. and Quintus.

by accident or by chance
not on accident and not on chance