“I live with and support my ex wife and her 19 yr old grandaughter.”----->To file your return as HOH status, you are unmarried or “considered unmarried”( You file a separate return; your spouse did not live in your home during the last 6 months of the tax year). on the last day of the year, 2011. Her 19YO granddaughter is NOT your qualifying child or qualifying relative, so you can’t claim the 19YO GD as a dependent for HOH. As long as she is your biological GD, you can claim her as a qualifying child/relative and can file your return as HOH. (but, you can’t file HOH on your ex-wife;she in neither your qualifying child nor qualifying reltive).
“My ex wife receives $820 a month disability (Social Security). Her grandaughter is a student (full time). “Can I file Head of Household (OR) claim either as a dependant? (Divorced more than 3 years)”----->As said above, No;you can’t. Also she is no longer your spouse, you can’t file MFJ/MFS with her, either. However, you can claim her, and 19YO GD(full time college student) as your dependents as long as they, unrelated persons, must live with you the ENTIRE YEAR. You pay more than 50% of the costs of keeping up a home for yourself and your ex and 19YO GD. However, If the relationship between you and the persons is violation of local law, then no dependency exemption is allowed. And their gross income is less than $3,650 for 2011.Your ex-spouse’s only source of support is through the Social Security Disability Insurance program, or SSD, you may be able to claim her as a dependent on your income tax return because Social Security Disability is not actually considered income for tax-related purposes.BUT REMEMEBER: you need to make sure her SSDI does not cover more than half of their own support. While SSDI does not count as income, even if it exceeds the maximum amount for tax-filing exemption status, it does count towards dependency status. For example, assume that she received $9,840 in Social Security disability in 2011, and you only paid, say, $9,000 towards support for the dependent that same year, you cannot claim her as a dependent for tax purposes as $9,840>$9,000.Youmust pay at least $9,840 towards support for her in 2011 to qualify the support test to claim her as your dependent.