Filing single & claiming a dependent - living together with both parents but filing separately & not married. how many months do each of us put, when technically is12 mo

[DawnC]

Only one of you can claim the child.   You can't split up child tax credits.   So, one of you will put all year, 12 months and the other will not list the dependent.   

[xmasbaby0]

Do you mean that you and the child's other parent all live together as a family with your child?  If so, only one of the parents can enter anything at all about the child on a tax return.   The other parent files as Single and does not enter anything at all about the child on a tax return .  

Only divorced or never married parents who live apart  and share custody of the child can say there is a signed agreement and split any of the child -related credits.    

You can figure your taxes out each way and decide----but in general the parent with the highest income is the one who should claim the child and file as Head of Household and get the child related credits.   Of course---you can share between yourselves when the HOH gets a tax refund.