The most accurate method is to add up the sales tax paid on each of your receipts. You can claim any sales tax you paid, regardless of where you paid it.
Since there are different methodologies for determining one’s local optional sales tax deduction, depending on one’s state or locality, the IRS Sales Tax Calculator can be used and will take an average of the sales tax assuming that you purchase items throughout the locality and not just in the taxing jurisdiction where you reside.
You can find the IRS calculator here: http://bit.ly/2tF87Kk
Please feel free to post any additional details or questions in the comment section.
There are two key features of a general sales tax: what is taxed (the tax base), and how much it is taxed (the tax rate). Among the states that have local sales taxes, these two features create three basic categories:
- Those in which the local tax base is the same as the state tax base and there is just one local sales tax rate throughout the state — in this case (e.g., Virginia), the local sales tax amount can be included with the state table using a combined rate on the same items.
- Those in which the local tax base is the same as the state tax base, but the local sales tax rates vary throughout the state — in this case the local sales tax amount can be derived from the state amount using the ratio of the local rate to the state rate.
- Those in which both the local tax bases and the local sales tax rates vary throughout the state — in this case the local sales tax amount must be derived independently from the state amount.
