How do people that aren't married that are just living together file their taxes?

You will each file singe - head of household since you are not married.

It's as if you are roomates or even renting a room to a stranger as far as taxes go. Just file as usual - as if you were single.

It's your child so, you should file head of household. Your BF can file single like always. It would be different if you were married or if one of you didn't work.

Taxpayers who share the same physical address will need to prove whether they "conduct themselves as separate households or one household" and especially "whether each family acts independently of each other in matters not related to the house." The IRS will attempt to figure out whether the taxpayers act as a family unit, or whether the taxpayers act as separate from each other. The more that two taxpayers act like they are in a family relationship, the less likely the IRS will allow both taxpayers to claim head of household. Due to the complexity of this situation, taxpayers who feel they qualify for head of household status even though they share the same address with another taxpayer should seek advice from an attorney, enrolled agent or certified public accountant before filing their tax returns. These professionals are trained to analyze situations and provide tax advice.

To get the most back you would want to be HoH so you get EIC. If he does HoH the kid cant be claimed.

Ask a tax person about it. You both still file separate. If you have kids with and with out him. then it might get tricky.

I always filed head of household and claimed my daughter. He filed single.

Is your boyfriend the father? If not, has the child(ren) been living with you for more than half of 2012? And for that matter, who is the custodial parent? You or the biological father? The custodial parent should claim head of household.