I am a 16 year old girl almost 17 in a month when I am 17 am I allowed to date a 21 year old?

Dating and sexual relations are two different matters. There's no rules on dating- it's up to your parent's discretion. However, every state has laws on the age of consent and what sexual contact is defined as. You'll need to find the laws for your state.

A 17 year old can date anyone they want, as long as their parents will permit them to. Parents can deny them dating at all, and restrict who they can date.

Well As Fair As I Know You Can But You Can't Have Sex Until Your Over 18..