Daughter turned 19 after she finished being a full time student in 2020. is she considered a full time student regardless?

Q.  Is she considered a full time student regardless of turning 19?

A. Yes. A child, under 24, who was a full time student for parts of 5 calendar months, can be considered a "qualifying child" (QC) dependent for the year, assuming the support and residence tests are met.  There is no income test for a QC. 

Q.   Does she file on her return that she was a full time student for 2020?  

A.  Yes, she checks the box that says she can be claimed as a dependent.  In TurboTax, she indicates that somebody else can claim her as a dependent, at the personal information section.  TT will check that box on form 1040.

Q.  If so, is she going to have to pay taxes for the unearned income?

A.  Yes, probably. You didn't say what the source of her unearned income is. Scholarships are treated better than other unearned income, for tax purposes.

If your dependent child  must file a tax return for 2020 if he had any of the following:

1.          Total income (wages, salaries, taxable scholarship etc.) of more than $12,400 (2020).
2.          Unearned income (interest, dividends, capital gains, unemployment) of more than $1100.
3.          Unearned income over $350 and gross income of more than $1100
4.          Household employee income (e.g. baby sitting, lawn mowing) over $2100 ($12,400 if under age 18)
5.          Other self employment income over $432, including money on a form 1099-NEC