Display formresults in same block as form
Solved it. Solution:

in function reiskosten_form_submit($form, &amp;$form_state) {

$result = drupal_json_decode($data-&gt;data);
$form_state['results'] = $result;


in function reiskosten_form($form, &amp;$form_state) {

$form['destination'] = array(
  '#markup' =&gt; '&lt;div&gt;' . $form_state['results']['destination_addresses'][0] . '&lt;/div&gt;',
);


Wrap t in an if to see if the values are there and the magic happens. Pfff