//Use user email address as auto generated password function wcs_filter_password_email( $args ) { $args['user_pass'] = $args['user_email']; //change user_email to whatever checkout field you want return $args; } add_filter( 'woocommerce_new_customer_data', 'wcs_filter_password_email' ); //Use user email address as login add_filter( 'woocommerce_new_customer_data', function( $data ) { $data['user_login'] = $data['user_email']; //change user_email to whatever checkout field you want return $data; } );