In line 5 on Schedule A, you can deduct either state and local income taxes here or state and local sales taxes. You can't do both.
From the IRS Instructions for Schedule A:
"If you elect to deduct state and local income taxes, you must check box a on line 5. Include on this line the state and local income taxes listed next.
- State and local income taxes withheld from your salary during 2016. Your Form(s) W-2 will show these amounts Forms W-2G, 1099-G, 1099-R, and 1099-MISC may also show state and local income taxes withheld.
- State and local income taxes paid in 2016 for a prior year, such as taxes paid with your 2015 state or local income tax return. Don't include penalties or interest.
- State and local estimated tax payments made during 2016, including any part of a prior year refund that you chose to have credited to your 2016 state or local income taxes.
- Mandatory contributions you made to the California, New Jersey, or New York Nonoccupational Disability Benefit Fund, Rhode Island Temporary Disability Benefit Fund, or Washington State Supplemental Workmen's Compensation Fund.
- Mandatory contributions to the Alaska, California, New Jersey, or Pennsylvania state unemployment fund.
- Mandatory contributions to state family leave programs, such as the New Jersey Family Leave Insurance (FLI) program and the California Paid Family Leave program."
If you live in a state without income taxes, you can choose to deduct your sales taxes. Tell TurboTax your state and local tax rates and it will compute the amount to deduct, based on an IRS table.
Note that you can deduct actual sales tax paid, if you kept all the receipts (which is why almost no one does it).
Also note that if you made a major purchase like a car or boat, you can add this sales tax to the computed sales tax from the table.
