WordPress at a glance
filter is not described

woocommerce_checkout_fields filter-hook . WC 1.0

Usage

add_filter( 'woocommerce_checkout_fields', 'filter_function_name_5941' );
function filter_function_name_5941( $fields ){
	// filter...

	return $fields;
}
$fields
-

Where the hook is called

WC_Checkout::get_checkout_fields()
woocommerce_checkout_fields
woocommerce/includes/class-wc-checkout.php 265
$this->fields = apply_filters( 'woocommerce_checkout_fields', $this->fields );

Where in WP core the hook is used WooCommerce

Usage not found.