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Open the sales tax panel, or create new
Choose ‘Advanced’
On the category you want to add taxes to, click the plus button to add a tax
Name it according to the tax authority, ie: state, county, federal or the name of the tax etc
Put the percentage into each category and they will be added together. For example in the example that follows the tax would be 7.5 + 3 = 10%10.5%
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What to do when multiple sales taxes compound another tax?
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