No, if they are not a dependent, you would not usually claim them. They might qualify you for Head of Household.
For the purposes of the Head of Household filing status, a qualifying person is a child, parent, or relative who meets certain conditions, listed below.
The conditions are stricter than those for claiming a dependent; for example, you might be able to claim a roommate as your dependent, but never as a qualifying person for Head of Household status.
A qualifying child would be:
- Your child (including legally adopted), stepchild, foster child, sibling, half-sibling, step-sibling, or a descendant of any of them (for example, your grandchild or niece) AND
- Permanently and totally disabled OR under the age of 19 as of December 31, 2018 (under 24 if a full-time student) and younger than you (or your spouse, if filing jointly) AND
- Lived with you for more than half the year AND
- Single (or if the child is married, you'd have to qualify to claim them as a dependent even if you're not going to claim them as such).
A child that is too old to qualify as a child might be able to qualify as a relative for Head of Household.
