diff --git a/resources/sql/autopatches/20150507.calendar.1.isallday.sql b/resources/sql/autopatches/20150507.calendar.1.isallday.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20150507.calendar.1.isallday.sql
@@ -0,0 +1,2 @@
+ALTER TABLE {$NAMESPACE}_calendar.calendar_event
+    ADD isAllDay BOOL NOT NULL;
diff --git a/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php b/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php
--- a/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php
+++ b/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php
@@ -21,6 +21,7 @@
     $types[] = PhabricatorCalendarEventTransaction::TYPE_DESCRIPTION;
     $types[] = PhabricatorCalendarEventTransaction::TYPE_CANCEL;
     $types[] = PhabricatorCalendarEventTransaction::TYPE_INVITE;
+    $types[] = PhabricatorCalendarEventTransaction::TYPE_ALL_DAY;
 
     $types[] = PhabricatorTransactions::TYPE_COMMENT;
     $types[] = PhabricatorTransactions::TYPE_VIEW_POLICY;
@@ -49,6 +50,8 @@
         return $object->getDescription();
       case PhabricatorCalendarEventTransaction::TYPE_CANCEL:
         return $object->getIsCancelled();
+      case PhabricatorCalendarEventTransaction::TYPE_ALL_DAY:
+        return $object->getIsAllDay();
       case PhabricatorCalendarEventTransaction::TYPE_INVITE:
         $map = $xaction->getNewValue();
         $phids = array_keys($map);
@@ -86,6 +89,7 @@
       case PhabricatorCalendarEventTransaction::TYPE_DESCRIPTION:
       case PhabricatorCalendarEventTransaction::TYPE_CANCEL:
       case PhabricatorCalendarEventTransaction::TYPE_INVITE:
+      case PhabricatorCalendarEventTransaction::TYPE_ALL_DAY:
         return $xaction->getNewValue();
       case PhabricatorCalendarEventTransaction::TYPE_STATUS:
         return (int)$xaction->getNewValue();
@@ -120,6 +124,9 @@
       case PhabricatorCalendarEventTransaction::TYPE_CANCEL:
         $object->setIsCancelled((int)$xaction->getNewValue());
         return;
+      case PhabricatorCalendarEventTransaction::TYPE_ALL_DAY:
+        $object->setIsAllDay((int)$xaction->getNewValue());
+        return;
       case PhabricatorCalendarEventTransaction::TYPE_INVITE:
       case PhabricatorTransactions::TYPE_COMMENT:
       case PhabricatorTransactions::TYPE_VIEW_POLICY:
@@ -143,6 +150,7 @@
       case PhabricatorCalendarEventTransaction::TYPE_STATUS:
       case PhabricatorCalendarEventTransaction::TYPE_DESCRIPTION:
       case PhabricatorCalendarEventTransaction::TYPE_CANCEL:
+      case PhabricatorCalendarEventTransaction::TYPE_ALL_DAY:
         return;
       case PhabricatorCalendarEventTransaction::TYPE_INVITE:
         $map = $xaction->getNewValue();
diff --git a/src/applications/calendar/storage/PhabricatorCalendarEvent.php b/src/applications/calendar/storage/PhabricatorCalendarEvent.php
--- a/src/applications/calendar/storage/PhabricatorCalendarEvent.php
+++ b/src/applications/calendar/storage/PhabricatorCalendarEvent.php
@@ -17,6 +17,7 @@
   protected $status;
   protected $description;
   protected $isCancelled;
+  protected $isAllDay;
   protected $mailKey;
 
   protected $viewPolicy;
@@ -84,6 +85,7 @@
         'status' => 'uint32',
         'description' => 'text',
         'isCancelled' => 'bool',
+        'isAllDay' => 'bool',
         'mailKey' => 'bytes20',
       ),
       self::CONFIG_KEY_SCHEMA => array(
diff --git a/src/applications/calendar/storage/PhabricatorCalendarEventTransaction.php b/src/applications/calendar/storage/PhabricatorCalendarEventTransaction.php
--- a/src/applications/calendar/storage/PhabricatorCalendarEventTransaction.php
+++ b/src/applications/calendar/storage/PhabricatorCalendarEventTransaction.php
@@ -9,6 +9,7 @@
   const TYPE_STATUS = 'calendar.status';
   const TYPE_DESCRIPTION = 'calendar.description';
   const TYPE_CANCEL = 'calendar.cancel';
+  const TYPE_ALL_DAY = 'calendar.allday';
   const TYPE_INVITE = 'calendar.invite';
 
   const MAILTAG_RESCHEDULE = 'calendar-reschedule';
@@ -37,6 +38,7 @@
       case self::TYPE_STATUS:
       case self::TYPE_DESCRIPTION:
       case self::TYPE_CANCEL:
+      case self::TYPE_ALL_DAY:
         $phids[] = $this->getObjectPHID();
         break;
       case self::TYPE_INVITE:
@@ -58,6 +60,7 @@
       case self::TYPE_STATUS:
       case self::TYPE_DESCRIPTION:
       case self::TYPE_CANCEL:
+      case self::TYPE_ALL_DAY:
       case self::TYPE_INVITE:
         return ($old === null);
     }
@@ -71,6 +74,7 @@
       case self::TYPE_END_DATE:
       case self::TYPE_STATUS:
       case self::TYPE_DESCRIPTION:
+      case self::TYPE_ALL_DAY:
       case self::TYPE_CANCEL:
         return 'fa-pencil';
         break;