Stop WooCommerce checkout fields auto-filling – leave blank

You can stop WooCommerce checkout fields from auto filling by using a Woo filter woocommerce_checkout_get_value, this could be useful in a situation when a logged in user is ordering on behalf of multiple customers.

add_filter( 'woocommerce_checkout_get_value','prefix_return_empty_checkout', 1, 1 );
function prefix_return_empty_checkout(){
	$user = wp_get_current_user();
        //The user has the "shop_manager" role
	if ( in_array( 'shop_manager', (array) $user->roles ) ) {
		return '';

So in the code snippet I am returning blank checkout fields just to the ‘Shop Manager’ role which is provided by WooCommerce, conditionally doing this allows regular Customers the user experience of having the checkout fields auto-fill. To apply for all users just remove the if condition.