US Sales Tax Calculator for Invoices

Five US states have no state sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon. However, some Alaska localities do levy local sales tax. If you select one of these states, the calculator will show $0 state sales tax.

Multiply the subtotal by the sales tax rate (as a decimal). For example, a $500 invoice with 8% sales tax: $500 x 0.08 = $40 tax. Total = $500 + $40 = $540. This calculator does it automatically for all 50 states with their current rates.

The average combined state and local sales tax rate in the US is approximately 6.6% as of 2025. State rates range from 0% (Oregon, Montana) to 7.25% (California). When local taxes are included, some areas exceed 10%. This calculator uses state-level rates for simplicity.

It depends on your state and what services you provide. Some states tax certain services (like consulting, digital products), while others only tax physical goods. Generally, if you sell tangible products, you must collect sales tax. Check your state Department of Revenue for specific rules. This calculator helps you compute the tax amount once you know your applicable rate.