Skip to content
Fluid Checkout
  • Demo
  • Features
  • Add-ons
    • Complete Bundle Save 42%
    • Fluid Checkout PRO
    • Google Address Autocomplete
    • Address Book
    • EU-VAT Assistant
  • Pricing PRO
  • Docs
  • Support
  • My account
0,00 € 0 items
Home / Docs / fc_vat_is_vat_number_field

How can we help?

Features

  • Proof of address for sales of digital goods

Customizations

  • Safely add code snippets to your WooCommerce website

Compatibility

  • Troubleshooting – jQuery events or vanilla JavaScript events not working

Troubleshooting

  • Troubleshooting – jQuery events or vanilla JavaScript events not working

Development

  • Filter and action hooks – EU-VAT Assistant
  • Changelog – Fluid Checkout EU-VAT Assistant
  • Troubleshooting – jQuery events or vanilla JavaScript events not working
  • Changelog format and semantic version numbers
View Categories

fc_vat_is_vat_number_field

Back to list of all filter and action hooks for EU-VAT Assistant.

Description #

Determines whether a specific field is considered a VAT number field, allowing to extend VAT logic to custom fields.

Parameters #

  • $is_vat_number_field (bool) Whether the field is a VAT number field.
  • $field_key (string) The field key/name.

Examples #

Enable VAT logic for custom fields #

/**
 * Enable VAT logic for custom fields
 */
function fc_vat_enable_logic_for_custom_fields_callback( $is_vat_number_field, $field_key ) {
    // Consider 'billing_tax_id' as a VAT number field
    if ( 'billing_tax_id' === $field_key ) {
        return true;
    }

    // Consider 'shipping_vat_number' as a VAT number field
    if ( 'shipping_vat_number' === $field_key ) {
        return true;
    }

    return $is_vat_number_field;
}
add_filter( 'fc_vat_is_vat_number_field', 'fc_vat_enable_logic_for_custom_fields_callback', 10, 2 );

Disable VAT logic for the default VAT field #

/**
 * Disable VAT logic for the default VAT field
 */
function fc_vat_disable_logic_for_default_field_callback( $is_vat_number_field, $field_key ) {
    // Disable VAT logic for the default billing_vat_number field
    if ( 'billing_vat_number' === $field_key ) {
        return false;
    }
    
    // Keep default behavior for all other fields
    return $is_vat_number_field;
}
add_filter( 'fc_vat_is_vat_number_field', 'fc_vat_disable_logic_for_default_field_callback', 10, 2 );

This code snippet is simply an example of how to use this hook. If you intend to disable the VAT validation for the default Billing VAT Number field, while keeping other features of the add-on, you should instead uncheck the option WP Admin > WooCommerce > Settings > Fluid Checkout > VAT Assistant > Validate VAT Number field for EU-VAT during checkout.

Still stuck? How can we help?

How can we help?

Updated on December 15, 2025
fc_vat_enable_compat_{$page}_style_{$theme_slug}
Table of Contents
  • Description
  • Parameters
  • Examples
    • Enable VAT logic for custom fields
    • Disable VAT logic for the default VAT field
Fluid Checkout

Frictionless Multi-step Checkout for WooCommerce

© 2021-2025 Fluid Checkout OÜ

Terms | Refunds | Privacy Policy | Cookies

Products
  • All products
  • Fluid Checkout PRO
  • Fluid Checkout Lite
  • Google Address Autocomplete add-on
  • Address Book add-on
  • EU-VAT Assistant add-on
Company
  • Support
  • Careers Hiring
  • My account
  • About
  • Homepage
  • Homepage
  • Features
  • Pricing PRO
  • Demo
  • Docs
  • Support
  • My account