The standard deduction for tax year 2020 is $24,800 for married filing joint, $12,400 for single, & $18,650 for Head of Household. The standard deduction reduces the amount of income you have to pay taxes on. You can either take the standard deduction or itemize (Schedule A).
If the amount on line 12 of 1040 was over the amount of your standard deduction, then Turbo Tax will select itemized deductions on your retrun, Otherwise, standard deduction will automatically be the other option .
