Remove default shipping methods from the dashboard (doesn't work to unset 'Flat Rate'). Great for cleaning up the shipping settings page and managing what shipping methods are available for site admins to manage.

unset-default-woocommerce-shipping-methods.php

<?php
/*
* Remove unused shipping rates from the dashboard
* note: WC_Shipping_Flat_Rate does not work here
* Defaults:
* 	- WC_Shipping_Free_Shipping 
*	- WC_Shipping_International_Delivery
*	- WC_Shipping_Local_Delivery
*	- WC_Shipping_Local_Pickup
*/
add_filter( 'woocommerce_shipping_methods', 'remove_unused_shipping_methods' );
function remove_unused_shipping_methods( $methods ) { 
	 // set the shipping methods you don't need
	$remove_shipping_methods = array(
		'WC_Shipping_Free_Shipping',
		'WC_Shipping_International_Delivery',
		'WC_Shipping_Local_Delivery',
		'WC_Shipping_Local_Pickup',
	);
	// loop over the methods, and unset them
	if( ! empty( $remove_shipping_methods ) ) {
		foreach( $remove_shipping_methods as $shipping_method ) {
			$position = array_search( $shipping_method, $methods );
			if( $position ) {
				unset( $methods[ $position ] );
				// reset the array/keys
				$methods = array_values( $methods );
			}
		}
	}
	return $methods; 
}
?>

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