diff --git a/api/src/Contacts.php b/api/src/Contacts.php
index 6046c41816..c5b96273d1 100755
--- a/api/src/Contacts.php
+++ b/api/src/Contacts.php
@@ -1022,6 +1022,15 @@ class Contacts extends Contacts\Storage
 				if (!isset($this->tracking)) $this->tracking = new Contacts\Tracking($this);
 				$this->tracking->track($to_write, $old ? $old : null, null, $deleted);
 			}
+
+			// Expire birthday cache for this year and next if birthday changed
+			if($isUpdate && $old['bday'] !== $to_write['bday'] || !$isUpdate && $to_write['bday'])
+			{
+				$year = (int) date('Y',time());
+				Cache::unsetInstance(__CLASS__,"birthday-$year-{$to_write['owner']}");
+				$year++;
+				Cache::unsetInstance(__CLASS__,"birthday-$year-{$to_write['owner']}");
+			}
 		}
 
 		return $this->error ? false : $contact['id'];
@@ -1676,6 +1685,68 @@ class Contacts extends Contacts\Storage
 		return $calendars;
 	}
 
+	/**
+	 * Read the holidays (birthdays) from the given addressbook, either from the
+	 * instance cache, or read them & cache for next time.  Cached for HOLIDAY_CACHE_TIME.
+	 *
+	 * @param int $addressbook - Addressbook to search.  We cache them separately in the instance.
+	 * @param int $year
+	 */
+	public function read_birthdays($addressbook, $year)
+	{
+		$birthdays = Cache::getInstance(__CLASS__,"birthday-$year-$addressbook");
+		if($birthdays !== null)
+		{
+			return $birthdays;
+		}
+
+		$birthdays = array();
+		$filter = array(
+			'owner' => (int)$addressbook,
+			'n_family' => "!''",
+			'bday' => "!''",
+		);
+		$bdays =& $this->search('',array('id','n_family','n_given','n_prefix','n_middle','bday'),
+			'contact_bday ASC',$extra_cols='',$wildcard='',$empty=False,$op='AND',$start=false,$filter);
+
+		if ($bdays)
+		{
+			// sort by month and day only
+			usort($bdays, function($a, $b)
+			{
+				return (int) $a['bday'] == (int) $b['bday'] ?
+					strcmp($a['bday'], $b['bday']) :
+					(int) $a['bday'] - (int) $b['bday'];
+			});
+			foreach($bdays as $pers)
+			{
+				if (empty($pers['bday']) || $pers['bday']=='0000-00-00 0' || $pers['bday']=='0000-00-00' || $pers['bday']=='0.0.00')
+				{
+					//error_log(__METHOD__.__LINE__.' Skipping entry for invalid birthday:'.array2string($pers));
+					continue;
+				}
+				list($y,$m,$d) = explode('-',$pers['bday']);
+				if ($y > $year)
+				{
+					// not yet born
+					continue;
+				}
+				$birthdays[sprintf('%04d%02d%02d',$year,$m,$d)][] = array(
+					'day'       => $d,
+					'month'     => $m,
+					'occurence' => 0,
+					'name'      => lang('Birthday').' '.($pers['n_given'] ? $pers['n_given'] : $pers['n_prefix']).' '.$pers['n_middle'].' '.
+						$pers['n_family'].
+						($GLOBALS['egw_info']['server']['hide_birthdays'] == 'age' ? ' '.($year - $y): '').
+						($y && in_array($GLOBALS['egw_info']['server']['hide_birthdays'], array('','age')) ? ' ('.$y.')' : ''),
+					'birthyear' => $y,	// this can be used to identify birthdays from holidays
+				);
+			}
+		}
+		Cache::setInstance(__CLASS__,"birthday-$year-$addressbook", $birthdays, 864000 /* 10 days*/);
+		return $birthdays;
+	}
+
 	/**
 	 * Called by delete-account hook, when an account get deleted --> deletes/moves the personal addressbook
 	 *
diff --git a/calendar/inc/class.calendar_bo.inc.php b/calendar/inc/class.calendar_bo.inc.php
index c84c01130a..77eaacc2f6 100644
--- a/calendar/inc/class.calendar_bo.inc.php
+++ b/calendar/inc/class.calendar_bo.inc.php
@@ -1879,7 +1879,7 @@ class calendar_bo
 			$contacts = new Api\Contacts();
 			foreach($contacts->get_addressbooks() as $owner => $name)
 			{
-				$holidays += calendar_holidays::read_addressbook($year, $owner);
+				$holidays += $contacts->read_birthdays($owner, $year);
 			}
 		}
 
diff --git a/calendar/inc/class.calendar_holidays.inc.php b/calendar/inc/class.calendar_holidays.inc.php
index 53fe377ea7..a18e74a282 100644
--- a/calendar/inc/class.calendar_holidays.inc.php
+++ b/calendar/inc/class.calendar_holidays.inc.php
@@ -35,7 +35,7 @@ class calendar_holidays
 	const URL_FAIL_CACHE_TIME = 300;
 	const EGW_HOLIDAY_URL = 'https://community.egroupware.org/egw';
 	const HOLIDAY_PATH = '/calendar/setup/ical_holiday_urls.json';
-	const HOLIDAY_CACHE_TIME = 864000; // 1 day
+	const HOLIDAY_CACHE_TIME = 864000; // 10 days
 
 	/**
 	 * Read holidays for given country/url and year
@@ -211,70 +211,6 @@ class calendar_holidays
 		return $urls[$country];
 	}
 
-
-	/**
-	 * Read the holidays (birthdays) from the given addressbook, either from the
-	 * instance cache, or read them & cache for next time.  Cached for HOLIDAY_CACHE_TIME.
-	 *
-	 * @param int $year
-	 * @param int $addressbook - Addressbook to search.  We cache them separately in the instance.
-	 */
-	public static function read_addressbook($year, $addressbook)
-	{
-		$birthdays = Api\Cache::getInstance(__CLASS__,"contacts-$year-$addressbook");
-		if($birthdays !== null)
-		{
-			return $birthdays;
-		}
-
-		$birthdays = array();
-		$contacts = new Api\Contacts();
-		$filter = array(
-			'owner' => (int)$addressbook,
-			'n_family' => "!''",
-			'bday' => "!''",
-		);
-		$bdays =& $contacts->search('',array('id','n_family','n_given','n_prefix','n_middle','bday'),
-			'contact_bday ASC',$extra_cols='',$wildcard='',$empty=False,$op='AND',$start=false,$filter);
-
-		if ($bdays)
-		{
-			// sort by month and day only
-			usort($bdays, function($a, $b)
-			{
-				return (int) $a['bday'] == (int) $b['bday'] ?
-					strcmp($a['bday'], $b['bday']) :
-					(int) $a['bday'] - (int) $b['bday'];
-			});
-			foreach($bdays as $pers)
-			{
-				if (empty($pers['bday']) || $pers['bday']=='0000-00-00 0' || $pers['bday']=='0000-00-00' || $pers['bday']=='0.0.00')
-				{
-					//error_log(__METHOD__.__LINE__.' Skipping entry for invalid birthday:'.array2string($pers));
-					continue;
-				}
-				list($y,$m,$d) = explode('-',$pers['bday']);
-				if ($y > $year)
-				{
-					// not yet born
-					continue;
-				}
-				$birthdays[sprintf('%04d%02d%02d',$year,$m,$d)][] = array(
-					'day'       => $d,
-					'month'     => $m,
-					'occurence' => 0,
-					'name'      => lang('Birthday').' '.($pers['n_given'] ? $pers['n_given'] : $pers['n_prefix']).' '.$pers['n_middle'].' '.
-						$pers['n_family'].
-						($GLOBALS['egw_info']['server']['hide_birthdays'] == 'age' ? ' '.($year - $y): '').
-						($y && in_array($GLOBALS['egw_info']['server']['hide_birthdays'], array('','age')) ? ' ('.$y.')' : ''),
-					'birthyear' => $y,	// this can be used to identify birthdays from holidays
-				);
-			}
-		}
-		Api\Cache::setInstance(__CLASS__,"contacts-$year-$addressbook", $birthdays, self::HOLIDAY_CACHE_TIME);
-		return $birthdays;
-	}
-
 }
 
 // some tests when url is called direct