Tax compliance is non-negotiable. ShopSTAR3 ships a capable built-in rules engine for stores with straightforward requirements, and native connectors for Avalara and TaxJar when jurisdiction complexity demands it. Either way, the store always gets accurate tax lines at checkout — calculated correctly the first time, on every order.
Tax Engine#
ShopSTAR3 supports two tax calculation approaches per store:
- Built-in rules engine — configure zones and rates directly in the platform. Suitable for stores with straightforward tax requirements.
- External tax engine — connect an Avalara or TaxJar account. The platform delegates all calculation to the external engine, which handles jurisdiction complexity, nexus determination, and compliance rules automatically. Credentials are stored securely and never exposed to storefront code.
Zones#
Define tax zones by country, state or province, and optional postal-code pattern. Each zone applies to the customer’s shipping or billing address (configurable per store). When multiple zones could match a destination, the most specific zone takes precedence.
Rates#
Configure one or more tax rates within each zone. Rates are assigned per product tax class:
| Tax Class | Use |
|---|---|
| Standard | Default rate — most physical goods |
| Reduced | Lower rate — food, books, and similar goods (jurisdiction-dependent) |
| Zero-rated | Applicable rate is 0% — exports and specific exempt categories |
| Exempt | No tax line applied |
A zone can carry multiple rates to model stacked tax jurisdictions (e.g. federal + state). Compound rates are calculated sequentially in priority order.
Inclusive Tax#
When inclusive tax is enabled for a zone, prices displayed to customers already include tax. At checkout the platform extracts and displays the included tax amount without changing the line item total.
Exemptions#
Customer-level tax exemptions — such as reseller certificates for B2B buyers — are configured in the Customer module. When a customer is marked as tax-exempt, all tax lines are suppressed at checkout regardless of zone and rate configuration.
Product tax classes are set in the Catalog module (Products section) and determine which rate within a zone applies to each line item. Shipping can also be assigned a tax class per store.
Reporting#
Tax amounts are stored on each order record. Tax summaries by period, zone, and rate are available through the Reporting module for filing and compliance purposes.