Restrict payment methods based on cart total

add_filter('woocommerce_available_payment_gateways', 'limit_payment_gateway_based_on_cart_total');

function limit_payment_gateway_based_on_cart_total($available_gateways) {

    if (is_admin() || !is_checkout()) {

        return $available_gateways;

    }

    // Get total cart

    $cart_total = WC()->cart->get_total('edit'); // Total cart without formattation

    // Set limit

    $limit = 1000; // Limit in local currency

    // If the total exceeds the limit, remove all gateways except BACS

    if ($cart_total > $limit) {

        foreach ($available_gateways as $gateway_id => $gateway) {

            if ($gateway_id !== 'bacs') { // BACS is the payment id to keep

                unset($available_gateways[$gateway_id]);

            }

        }

    }

    return $available_gateways;

}