In WooCommerce 3.6 or later you can use woocommerce_add_to_cart_redirect
(props @roman)
add_filter ('woocommerce_add_to_cart_redirect', function( $url, $adding_to_cart ) {
return wc_get_checkout_url();
}, 10, 2 );
Original answer:
you can use a filter in functions.php:
add_filter ('add_to_cart_redirect', 'redirect_to_checkout');
function redirect_to_checkout() {
global $woocommerce;
$checkout_url = $woocommerce->cart->get_checkout_url();
return $checkout_url;
}
it doesn’t seem to work with ajax, but it works from the single product pages, which I think is what you use
On WooCommerce (>= 2.1) the function can be simplified as:
function redirect_to_checkout() {
return WC()->cart->get_checkout_url();
}