- 1). Determine the amount you paid in sales tax on your automobile purchase. Be sure you have appropriate documentation to support your claim.
- 2). Check the "General Sales Tax" box on line 5b of your Schedule A for itemized deductions.
- 3). Write the amount of sales tax you paid for your car on line 5 of your Schedule A.
- 4). Total the value of all of your itemized deductions and write the result on line 29 of the Schedule A form.
- 5). Enter the amount from line 29 of the Schedule A onto line 40 of your Form 1040 tax return to complete the claiming of the deduction.
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