Try the IRS Sales Tax Deduction Calculator. For most people who itemize, the state and local income tax deduction gives them a bigger tax break. However, the sales tax deduction may be more advantageous for taxpayers who:
Are residents of Alaska, Florida, Nevada, South Dakota, Texas, Washington, or Wyoming
Made a major purchase and therefore paid a lot of sales tax
Made frequent or substantial purchases in a state with high sales taxes
TurboTax will let you know which deduction saves you the most money based on your situation.