Even if it seems like everyone your age is having sex, they’re probably not. Only about half of high school students have ever had vaginal sex, and the average age when people start having sex is 18. But even once they have had sex, most teens don't have it very often. And lots of teens who've had sex say they wish they’d waited. You’re not ready to have sex if the reason you want to sounds anything like: I’m the only virgin in my group of friends. I want to “get it over with.” My boyfriend or girlfriend will break up with me if I don’t have sex. Having sex will make me popular. I’ll feel older if I have sex.