"Smart Coupons for WooCommerce" eklentisi: veya "WooCommerce Extended Coupon Features" eklentisi: olabilir birde
şu fonkisoyn kodu ile eklenebilir

add_action( 'woocommerce_before_add_to_cart_button', 'add_coupon_field_to_product_page' );
 
function add_coupon_field_to_product_page() {
 
    global $product;
 
    echo '<div class="coupon">';
    woocommerce_form_field( 'coupon_code', array(
        'type' => 'text',
        'class' => array(
            'my-field-class form-row-wide'
        ),
        'label' => __('Kupon Kodu', 'woocommerce'),
        'placeholder' => __('Kupon Kodu Girin', 'woocommerce'),
        'required' => false,
    ), '' );
    echo '</div>';
 
}