TurboTax automatically applies the standard deduction to your taxes when you first begin. It will continue to use the standard deduction until you enter enough itemized deductions to total more than the standard deduction. TurboTax will automatically switch to itemized deductions when they total more than the standard deduction.
There are limits and/or thresholds on certain itemized deductions. Only the amount of deductible medical expenses in excess of 7.5% of your AGI can be deducted. The SALT deduction (real estate taxes, state and local income or sales taxes, and other deductible taxes) are limited to a maximum of $10,000. Many deductions that could be taken prior to 2018 have been eliminated.
Standard deductions were substantially increased beginning with tax year 2018:
Single - $12,200 add $1,600 if age 65 or older
Married Filing Separately - $12,200 add $1,600 if age 65 or older
Married Filing Jointly - $24,400 add $1,300 for each spouse age 65 or older
Head of Household - $18,350 add $1,600 if age 65 or older
