What Is Tax-Inclusive Pricing?

When Prices Include Tax is enabled, the prices you set for your products are treated as already including tax - the tax component is extracted from the price rather than added on top at checkout.

When disabled, the tax rate is added on top of the product price at checkout.

This setting can be configured globally under the Global Tax tab, and overridden per location under the Location based Tax Rates tab - both found at Pricing & Payments > Tax Settings.