no matter what you do your gf will have to paper file if she claims the child. IRS rules when two people claim the first can e-file the second must mail.
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you have provided no info so here are the rules for claiming a child. i have left out the rules that seem irrelevant in this situation
- Related to you - son. daughter.
- Same principal abode as you for more than ½ the tax year (usually, unless you live together only one of you can meet this rule. It's based on the number of nights the child spent with the taxpayer)
- A US citizen, resident alien or national, or a resident of Canada or Mexico
- If a qualifying child of more than one person there are tie-breaker rules
it you live together it would seem both of you qualify so either can claim but not both
however, for you, your filing status would go from head of household to single.
you can not amend until the initial return you filed is completely processed and you get your refund.
