I live in the US and have a daughter who turned 24 in September (full-time student). I have claimed her as a dependent in the past. Can I claim head of household filing status this year, or is she now too old to be considered a dependent?
A relative related by blood, legal adoption, or marriage other than a parent (child, sibling, grandparent, nephew, aunt, step-parent, in-law, etc.) AND lived with you for more than half the year AND that you're able to claim as a dependent (even if you're not claiming them as such).
This is the criteria for head of household, if your child is too old to claim as a child. In your case, paying for half the support should do it.