You say he has separate housing. That means he does not live with you. That means he cannot be your qualifying child (QC).
That means we go to the qualifying relative (QR) rules, to see if he can be your dependent. The support rule for a QR is different than for a QC. For a QC it is that he did not provide more than 1/2 his own support. For a QR, it is that the taxpayer (you) provide more than half his support. So, his SSI income works against you, because it is third party (welfare) support and not support provide by you.
Full rules at
It depends. Generally to qualify as a dependent your child would have to live with you at least 1/2 of the year and you would have to provide more than 1/2 of their support.
Here are a couple of links that will help you determine if your child qualifies as a dependent: IRS Children with Disabilities Who Can I claim as a Dependent
the links seem to address primarily earned income credit. I'm trying to identify dependent and filing status. I seem to find conflicting information and I also get confused......... He has only SSI which tells me his SSI $$ don't count as income for tax purposes, but does it count for determining 50% expenses being pd by himself? I found where SSI doesn't count since it is not considered his income, rather it is 'welfare'. So would I be correct to assume that if welfare pays 1/2 or more of his expenses..... I probably just answered my question, huh? that if I don't pay over 1/2, regardless of where the money comes from to pay the other, I can't be H of H or dependent? Thjanks.
You say he has separate housing. That means he does not live with you. That means he cannot be your qualifying child (QC).
That means we go to the qualifying relative (QR) rules, to see if he can be your dependent. The support rule for a QR is different than for a QC. For a QC it is that he did not provide more than 1/2 his own support. For a QR, it is that the taxpayer (you) provide more than half his support. So, his SSI income works against you, because it is third party (welfare) support and not support provide by you.
Full rules at