Si hay un descuento en ese pedido, puede agregar otra etiqueta de fila de tabla y calcular el porcentaje. Así que sería algo como esto:

 add_action('woocommerce_cart_totals_after_order_total', 'wc_discount_total', 99); add_action('woocommerce_review_order_after_order_total', 'wc_discount_total', 99); function wc_discount_total() { global $woocommerce; $discount_total = 0; foreach ($woocommerce->cart->get_cart() as $cart_item_key => $values) { $_product = $values['data']; if ($_product->is_on_sale()) { $regular_price = $_product->get_regular_price(); $sale_price = $_product->get_sale_price(); $discount = ($regular_price - $sale_price) * $values['quantity']; $discount_total += $discount; } } if ($discount_total > 0) { echo '<tr class="cart-discount"> <th>' . __('Your Savings', 'woocommerce') . '</th> <td data-title=" ' . __('You Saved', 'woocommerce') . ' ">' . wc_price($discount_total + $woocommerce->cart->discount_cart) . '</td> </tr>'; $total = WC()->cart->cart_contents_total; $total_saved = wc_price($discount_total + $woocommerce->cart->discount_cart); $percentage_saved = round(($total_saved * 100) / $total); echo '<tr class="cart-percentage-discount"> <th>' . __('Percentage Saved', 'woocommerce') . '</th> <td data-title=" ' . __('You Saved', 'woocommerce') . ' ">' . esc_html($percentage_saved . "%") . '</td> </tr>'; } }