Amazon's Tax Calculation Service has a custom rate option that offers you the ability to assign a static percentage to be calculated on orders destined to a specific state. A custom rate will override your product tax code (PTC) rules (sales tax holiday, reduced rate, etc.) and jurisdictional tax rate(s) supplied by our tax software provider with your custom rate to be calculated at the state level.
A custom rate is an override to our service. You must have a product tax code assigned at the item and/or default level that the custom rate can override. The custom rate option will not override PTC assignment A_GEN_NOTAX (items designated as “Always Non-taxable”) or a zero rated jurisdiction (state jurisdiction with a zero tax rate, such as Oregon).
Per your Tax Calculation Services Terms, if you assign a custom rate to calculate tax, you must in good faith set a rate that accurately reflects a jurisdiction’s actual sales or use tax rate.
To specify a custom rate for individual states, follow the steps given below:
Your custom rate will calculate at the state jurisdiction level only and the PTC will appear as A_CUSTOM_RATE in your sales tax report.
You are responsible for identifying your Tax obligations in addition to the calculation, remittance, and reporting of all taxes within your obligation, regardless of your participation in Amazon’s Tax Calculation Service. For more information, see our Tax Policies.