diff --git a/uc_signup.module b/uc_signup.module
index 45eb4b4..63f5e38 100644
--- a/uc_signup.module
+++ b/uc_signup.module
@@ -728,7 +728,7 @@ function uc_signup_add_to_cart($nid, $qty, $data) {
 function uc_signup_cart_view_form_submit($form, &$form_state) {
   // If quantity of any items has been decreased, unset the extra attendee 
   // email addresses from $_SESSION['uc_signup']['nids'].
-  if ($form_state['values']['op'] == t('Update cart')) {
+if ($form_state['values']['op'] == t('Update cart') || $form_state['values']['op'] == t('Checkout')) {
     foreach ($form_state['values']['items'] as $name => $item) {
       if ($item['qty'] < count($_SESSION['uc_signup']['nids'][$item['nid']])) {
         array_splice($_SESSION['uc_signup']['nids'][$item['nid']], $item['qty']);