WooCommerce Percentage Checkout Admin/Handling Fee

About This Solution

A little warning, unexpected fees at checkout can put some users off and some payment gateways do not allow custom additional fees. Passing on fees and surcharges may not be legal in your location so do check before implementing this code snippet. Adding a percentage amount fee at checkout based on the cart total for handling or administration costs is really easy and appears in the order summary box as an order item. Once the order is paid for, the admin fee is shown in the cart, on the order received thank you page, order editor as a line item, and in all of the post-purchase emails where the order table appears. This particular guide adds a 10% surcharge to the order.

/**
 * Snippet Name:	Add a percentage handling/admin fee to the order
 * Snippet Author:	ecommercehints.com
 */

add_action( 'woocommerce_cart_calculate_fees','ecommercehints_percentage_checkout_fee' );
function ecommercehints_percentage_checkout_fee() {
  global $woocommerce;

	if ( is_admin() && ! defined( 'DOING_AJAX' ) )
		return;

	$percentage = 0.1;// The percentage fee
	$surcharge = ( $woocommerce->cart->cart_contents_total + $woocommerce->cart->shipping_total ) * $percentage;
	$woocommerce->cart->add_fee( 'Admin Fee', $surcharge, true, '' ); // The order item label

}