Szamlazz.hu VAT/Checkout Compatibility

Use this skill when a plugin/theme must cooperate with the Szamlazz.hu WooCommerce VAT/tax-number workflow. The goal is one source of truth for company billing and VAT data, so invoices, checkout validation, customer addresses, subscription renewals, admin orders, and Store API checkout all agree.

The plugin's VAT feature loads only when its vat_number_type option is not no. Guard your integration for sites where the Szamlazz.hu VAT UI is disabled.

Version 6.2 added the "VAT number for all countries" path and made wc_szamlazz_vat_number_validation_results run for invalid VAT results too. Version 6.2.2 further adjusts EU VAT validation behavior. This skill was rechecked against the local 6.2.2 source and WooCommerce 10.9.4.

When to use this skill

Trigger when ANY of these are true:

• Adding or auditing a WooCommerce B2B/company billing field.
• Mapping another plugin's VAT number into Szamlazz.hu invoices.
• Supporting classic checkout and Checkout Blocks/Store API with the same VAT state.
• Debugging required VAT/company validation, EU VAT exemption, or VIES/NAV validation.
• The code touches wc_szamlazz_adoszam, _billing_wc_szamlazz_adoszam, _wc_szamlazz_adoszam_data, wc-szamlazz-vat-number, wc_szamlazz_xml_adoszam, wc_szamlazz_vat_number_validation_results, or woocommerce_store_api_checkout_update_order_from_request.

Canonical data contract