WooCommerce: Display Shipping Estimates with methods on cart / checkout

wc-shipping-estimate.php

<?php
/**
 * only copy opening php tag if needed
 * Displays shipping estimates for WC shipping rates
 */
function sv_shipping_method_estimate_label( $label, $method ) {

	$label .= '<br /><small>';

	switch ( $method->method_id ) {
		case 'flat_rate':
			$label .= 'Est delivery: 2-4 days';
			break;

		case 'free_shipping':
			$label .= 'Est delivery: 4-7 days';
			break;

		case 'international_delivery':
			$label .= 'Est delivery: 7-10 days';
			break;

		default: 
			$label .= 'Est delivery: 3-5 days';
	}
	
	$label .= '</small>';
	return $label;
}
add_filter( 'woocommerce_cart_shipping_method_full_label', 'sv_shipping_method_estimate_label', 10, 2 );