diff --git a/src/applications/settings/controller/PhabricatorSettingsTimezoneController.php b/src/applications/settings/controller/PhabricatorSettingsTimezoneController.php
--- a/src/applications/settings/controller/PhabricatorSettingsTimezoneController.php
+++ b/src/applications/settings/controller/PhabricatorSettingsTimezoneController.php
@@ -63,7 +63,7 @@
 
     $server_offset = $viewer->getTimeZoneOffset();
 
-    if ($client_offset == $server_offset || $did_calibrate) {
+    if (($client_offset == $server_offset) || $did_calibrate) {
       return $this->newDialog()
         ->setTitle(pht('Timezone Calibrated'))
         ->appendParagraph(
@@ -113,12 +113,14 @@
   }
 
   private function formatOffset($offset) {
-    $offset = $offset / 60;
-
-    if ($offset >= 0) {
-      return pht('UTC-%d', $offset);
+    // Non-integer number of hours off UTC?
+    if ($offset % 60) {
+      $hours = $offset / 60;
+      $minutes = abs($offset % 60);
+      return pht('UTC%+d:%02d', $hours, $minutes);
     } else {
-      return pht('UTC+%d', -$offset);
+      $hours = $offset / 60;
+      return pht('UTC%+d', $hours);
     }
   }