Alaska, Delaware, Montana, New Hampshire, and Oregon have no statewide sales tax. However, some Alaska localities charge local sales tax. If you're in these states and paid sales tax on an out-of-state or online purchase, use reverse calculation with that rate. For Alaska local tax jurisdictions, use the specific local rate. In other no-tax states, you typically won't need reverse calculations unless dealing with out-of-state purchases subject to use tax.

Proper reverse tax calculations ensure compliance by maintaining accurate records of tax collected, properly separating revenue from tax liability, enabling correct tax return filing, supporting audit defense, and demonstrating systematic business practices to tax authorities. Compliance requires showing that tax was correctly calculated on appropriate base amounts. Reverse calculations provide this documentation and verification mechanism.

While Alaska has no state sales tax, many local jurisdictions (cities and boroughs) impose local sales taxes ranging from 1% to 7%. If you made a purchase in an Alaska city with local tax, check your receipt for the rate charged or look up the local tax rate for that specific city. Use this rate in the reverse calculator. Anchorage, Fairbanks, and Juneau have different rates, and some remote areas have no sales tax at all.