I'm 19 and my girlfriend is 15. We have never had sex, but I want to know when does it become legal, and if she becomes emancipated does that change anything. Thanks

First, it depends on where you live. We can't tell you the law in your area without knowing your area. We don't need your exact address, just a state/province, country, etc.

Most countries (not all) have laws to protect children, and until the age of 18 your girlfriend is considered a child in most countries, at 19 you're an adult. There are laws for sex, age of consent laws. Most are 16, some are higher, some are lower, and most all of them have a difference in age clause, meaning that if you're more than 2 or 3 years old than the 16 year old, you could be in a lot of legal trouble. Once a child is 18, the laws are less strict.

Until a child reaches the age of consent his or her (her in this case) parents, have a say on dating, when it's allowed, and who she's allowed to date. Even if you're not having sex, if this 15 year old child's parents don't agree with her dating, she can't date. To do so against her parents wishes could land you in trouble. Not her.

Becoming emancipated isn't as easy as many teens think it is. You can't just say "I don't like mommy and daddy's rules so I'm leaving", and then become emancipated. In order for her to do this legally she would have to prove that she can support herself. That means getting a job that makes enough money to get a roof over her head, food on the table, pay all necessary bills (doctor, dentist, heat, water, etc) without any help from anyone. She can't just leave and move in with you. That's not conducive to being emancipated.

What has her parents said about you being with their daughter? They are the ones that decide if you are acceptable or not. They are the ones to bring the cops in to decide if this is illegal or NOT. Or if she can be emancipated or NOT. That's who I would ask if I were you.

What is your problem that you can only get a 15 yr old as a girlfriend? The difference in maturity and interests between 15 and 19 is vast. I can't imagine what a 19 yr old would see in a 15 yr old. You are in college or working, she is just starting high school.

There are no laws on dating. However until she is an adult her parents control who she can be with. And if you go against her parent's wishes, you can get in legal trouble.

The fact that you ask about emancipation suggests that there are issues with her parents which makes me wonder about your relationship.

I'll reemphasize what was said: if her parents want to get you in trouble, they can, regardless of what you do with each other.
Having said that, research YOUR STATE and the following terms, one at a time:
Age of consent
Age of majority
Romeo and Juliet laws (age differences)
Emancipation

AND various terms such as risk of injury to a minor, endangering a minor, etc.

So my take on this is that she said she can leave whenever she wants to. Not so. Emancipation is a BIG word nowadays when kids are so unhappy with their home life, they can't wait to leave and be 'emancipated'. What this means, is if they have another way of supporting themselves other then their parents, and probably going to school at the same time. Doesn't work out that way.

You have no business fooling with this kid's mind and come here and ask if it is okay. It isn't. Her parents can incarcerate you for a very long time for abusing a minor. Think about how that will be in jail when other jailmates find out what you are in for?

It is my understanding that men who have been involved with minors are held accountable inside for that and do not survive a whole term.

First she is not going to get emancipated, that is a very hard legal process that can take over a year or more and at 15, normally if there are serious home issues, she will end up in Children's service not emancipated

Next having sex will depend on where you are at, Here in China it is 14, that they can have sex. In some places in world, it is 16, others 17.

The other issue, the girl also has to even have permission from parents to date you, so you can get into trouble if parents donot know about you, and have not given permission

We have never had sex, but I want to know when does it become legal

Clearly you are planning to have sex with her as soon as you can't be prosecuted for it. That is not a good sign. I wonder how long you have been dating her and whether her parents know and approve.