As of API version 2026-01, the tax_summaries/create webhook and tax calculation requests for Tax Partner Apps include additional fields for currency. These fields provide amounts in both shop currency and presentment currency. This enhancement allows tax Partners to perform calculations and reporting in the merchant's accounting currency while maintaining the customer-facing currency for display.
This is a companion discussion topic for the original entry at https://shopify.dev/changelog/tax-summary-webhook-and-calculation-requests-now-includes-shop-and-presentment-currency-amount