diff --git a/addressfield.module b/addressfield.module
index 25b277d..cd07aab 100644
--- a/addressfield.module
+++ b/addressfield.module
@@ -429,7 +429,7 @@ function addressfield_field_is_empty($item, $field) {
 function addressfield_field_presave($entity_type, $entity, $field, $instance, $langcode, &$items) {
   foreach ($items as $delta => &$item) {
     // If the first name and last name are set but the name line isn't...
-    if (isset($item['first_name']) && isset($item['last_name']) && !isset($item['name_line'])) {
+    if (isset($item['first_name']) && isset($item['last_name']) && empty($item['name_line'])) {
       // Combine the first and last name to be the name line.
       $items[$delta]['name_line'] = $items[$delta]['first_name'] . ' ' . $items[$delta]['last_name'];
     }