Ar Interactive Brokers you have to be at least 21 years of age. Perhaps that's the norm.
Quote from bender271:
I thought they refused to give me margin privilege because i am a full time student and don't have a job. Yes, I am 20- will be 21 in a month or so.
It's just so hard not having margin... Have to wait 3 days for the funds to clear and can't even short a stock!