To claim a parent as a dependent they must meet all the requirements under the Qualifying Relative rules. Other than the income requirement the other main requirement is that you provided over one-half of the support. You can use the IRS worksheet for determining support - https://apps.irs.gov/app/vita/content/globalmedia/teacher/worksheet_for_determining_support_4012.pdf
To be a Qualifying Relative -
1. The person cannot be your qualifying child or the qualifying child of any other taxpayer. A child is not the qualifying child of any other taxpayer if the child's parent (or any other person for whom the child is defined as a qualifying child) is not required to file an income tax return or files an income tax return only to get a refund on income tax withheld.
2. The person either (a) must be related to you or (b) must live with you all year as a member of your household.
3. The person's gross income for the year must be less than $4,050 (social security does not count) in 2016
4. You must provide more than half of the person's total support for the year.
5. The person must be a U.S. citizen or a U.S., Canada, or Mexico resident for some part of the year.
6. The person must not file a joint return with their spouse.
To claim a parent as a dependent they must meet all the requirements under the Qualifying Relative rules. Other than the income requirement the other main requirement is that you provided over one-half of the support. You can use the IRS worksheet for determining support - https://apps.irs.gov/app/vita/content/globalmedia/teacher/worksheet_for_determining_support_4012.pdf
To be a Qualifying Relative -
1. The person cannot be your qualifying child or the qualifying child of any other taxpayer. A child is not the qualifying child of any other taxpayer if the child's parent (or any other person for whom the child is defined as a qualifying child) is not required to file an income tax return or files an income tax return only to get a refund on income tax withheld.
2. The person either (a) must be related to you or (b) must live with you all year as a member of your household.
3. The person's gross income for the year must be less than $4,050 (social security does not count) in 2016
4. You must provide more than half of the person's total support for the year.
5. The person must be a U.S. citizen or a U.S., Canada, or Mexico resident for some part of the year.
6. The person must not file a joint return with their spouse.
Note that there is no requirement that they live with you. But if you are not furnishing their housing, the support value of a home is the fair market rental value, divided by the number of occupants., in determining if you meet the support requirement. That is, even if their house is paid for (no mortgage) the house is still considered support they provide for themselves.