My 22 year old daughter is the only one with taxable income can she file head of household the tax return with me and her grandmother who get ssdi.

[bluedeb · Accepted solution]

No, she cannot file as Head of Household, she would need a qualifying child or dependent.

Who qualifies as head of household?

To file as head of household, you must: Pay for more than half of the household expenses. Be considered unmarried on the last day of the tax year, and. You must have a qualifying child or dependent.

[DoninGA]

Probably not.  Assuming that all of you contribute to the household and each of you provide for your own support with benefits received from Social Security.

For Head of Household filing status she would need to be providing over one-half the cost for the household (rent, mortgage, utilities, etc.) plus provided over one-half of the support for you and her grandmother under the Qualifying Relative rules for claiming a dependent.

See this TurboTax support FAQ for Head of Household - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-filing-status/qualify-head-household...

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 $4,400 (social security does not count) in 2022
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.

[Hal_Al]

So, the next question is do you or her grandmother qualify as her dependent. Probably not.

There are two types of dependents, "Qualifying Children"(QC) and Other ("Qualifying Relative" in IRS parlance even though they don't have to actually be related). There is no income limit for a QC but there is an age limit and student status test, a relationship test and a residence test. 

A person can still be a Qualifying relative dependent, if not a Qualifying Child, if he meets the 6 tests for claiming a dependent:

1. Closely Related (parent & grandparent count) OR live with the taxpayer ALL year
2. His/her gross taxable income for the year must be less than $4300 (2021).
3. The taxpayer must have provided more than 1/2 his support

In either case:

4. He must be a US citizen or resident of the US, Canada or Mexico
5. He must not file a joint return with his spouse or be claiming a dependent of his own
6. He must not be the qualifying child of another taxpayer

Nontaxable Social security (including SSDI) doesn't count as income, for the income test (#2), but social security money he/she spends on her self does count as support not provided by you, for the support test (#3). Money she puts into savings & investment does not count as support she spent on herself. Note that a parent/grandparent is closely related so there is no requirement that she live with you at any time, during the year. But if you provided a home it helps your support case, unless they own the home you live in. 

The IRS has a worksheet that can be used to help with the support calculation. See: http://apps.irs.gov/app/vita/content/globalmedia/teacher/worksheet_for_determining_support_4012.pdf The support value of a home is the fair market rental value, divided by the number of occupants.

[Mike9241]

assuming your daughter is not a surviving widow whose spouse died in the last two years or was not legally wed on 12/31/21 she can claim the following dependents and file as head of household if these tests are met. 

for you, her parent,  assuming you will not file a joint return with your spouse, you must have lived with her for the whole year or she paid more than 1/2 the cost of keeping up your main home. 

for her grandmother, assuming she will not file a joint return with her spouse, and your daughter provided over 1/2 of her support and her gross income was less than $4300. SSDI does not count towards gross income