diff --git a/CRM/Contact/BAO/Group.php b/CRM/Contact/BAO/Group.php
index 6885eec95e27..6ebf3b8b96af 100644
--- a/CRM/Contact/BAO/Group.php
+++ b/CRM/Contact/BAO/Group.php
@@ -910,7 +910,7 @@ public static function getGroupList(&$params) {
     $links = self::actionLinks();
 
     $allTypes = CRM_Core_OptionGroup::values('group_type');
-    $values = $groupsToCount = array();
+    $values = array();
 
     $visibility = CRM_Core_SelectValues::ufVisibility();
 
@@ -964,8 +964,6 @@ public static function getGroupList(&$params) {
 
       $values[$object->id]['visibility'] = $visibility[$values[$object->id]['visibility']];
 
-      $groupsToCount[$object->saved_search_id ? 'civicrm_group_contact_cache' : 'civicrm_group_contact'][] = $object->id;
-
       if (isset($values[$object->id]['group_type'])) {
         $groupTypes = explode(CRM_Core_DAO::VALUE_SEPARATOR,
           substr($values[$object->id]['group_type'], 1, -1)
@@ -1017,20 +1015,9 @@ public static function getGroupList(&$params) {
         $contactUrl = CRM_Utils_System::url('civicrm/contact/view', "reset=1&cid={$object->created_id}");
         $values[$object->id]['created_by'] = "<a href='{$contactUrl}'>{$object->created_by}</a>";
       }
-    }
 
-    // Get group counts - executes one query for regular groups and another for smart groups
-    foreach ($groupsToCount as $table => $groups) {
-      $where = "g.group_id IN (" . implode(',', $groups) . ")";
-      if ($table == 'civicrm_group_contact') {
-        $where .= " AND g.status = 'Added'";
-      }
-      // Exclude deleted contacts
-      $where .= " and c.id = g.contact_id AND c.is_deleted = 0";
-      $dao = CRM_Core_DAO::executeQuery("SELECT g.group_id, COUNT(*) as `count` FROM $table g, civicrm_contact c WHERE $where GROUP BY g.group_id");
-      while ($dao->fetch()) {
-        $values[$dao->group_id]['count'] = $dao->count;
-      }
+      // get group contact count using Contact.GetCount API
+      $values[$object->id]['count'] = civicrm_api3('Contact', 'getcount', array('group' => $object->id));
     }
 
     // CRM-16905 - Sort by count cannot be done with sql
@@ -1356,23 +1343,39 @@ protected function assignTestValue($fieldName, &$fieldDef, $counter) {
   /**
    * Get child group ids
    *
-   * @param array $ids
+   * @param array $regularGroupIDs
    *    Parent Group IDs
    *
    * @return array
    */
-  public static function getChildGroupIds($ids) {
-    $notFound = FALSE;
-    $childGroupIds = array();
-    foreach ($ids as $id) {
-      $childId = CRM_Core_DAO::getFieldValue('CRM_Contact_DAO_Group', $id, 'children');
-      while (!empty($childId)) {
-        $childGroupIds[] = $childId;
-        $childId = CRM_Core_DAO::getFieldValue('CRM_Contact_DAO_Group', $childId, 'children');
+  public static function getChildGroupIds($regularGroupIDs) {
+    $childGroupIDs = array();
+
+    foreach ($regularGroupIDs as $regularGroupID) {
+      // temporary store the child group ID(s) of regular group identified by $id,
+      //   later merge with main child group array
+      $tempChildGroupIDs = array();
+      // check that the regular group has any child group, if not then continue
+      if ($childrenFound = CRM_Core_DAO::getFieldValue('CRM_Contact_DAO_Group', $regularGroupID, 'children')) {
+        $tempChildGroupIDs[] = $childrenFound;
+      }
+      else {
+        continue;
+      }
+      // as civicrm_group.children stores multiple group IDs in comma imploded string format,
+      //   so we need to convert it into array of child group IDs first
+      $tempChildGroupIDs = explode(',', implode(',', $tempChildGroupIDs));
+      $childGroupIDs = array_merge($childGroupIDs, $tempChildGroupIDs);
+      // recursively fetch the child group IDs
+      while (count($tempChildGroupIDs)) {
+        $tempChildGroupIDs = self::getChildGroupIds($tempChildGroupIDs);
+        if (count($tempChildGroupIDs)) {
+          $childGroupIDs = array_merge($childGroupIDs, $tempChildGroupIDs);
+        }
       }
     }
 
-    return $childGroupIds;
+    return $childGroupIDs;
   }
 
 }
diff --git a/CRM/Contact/BAO/Query.php b/CRM/Contact/BAO/Query.php
index d519eeef4337..4a8915abc3ff 100644
--- a/CRM/Contact/BAO/Query.php
+++ b/CRM/Contact/BAO/Query.php
@@ -2979,31 +2979,42 @@ public function group($values) {
     }
     $groupClause = array();
     if (count($regularGroupIDs) || empty($value)) {
+      // include child groups IDs if any
+      $childGroupIds = (array) CRM_Contact_BAO_Group::getChildGroupIds($regularGroupIDs);
+      foreach ($childGroupIds as $key => $id) {
+        if (CRM_Core_DAO::getFieldValue('CRM_Contact_DAO_Group', $id, 'saved_search_id')) {
+          $smartGroupIDs[] = $id;
+          unset($childGroupIds[$key]);
+        }
+      }
+      if (count($childGroupIds)) {
+        $regularGroupIDs = array_merge($regularGroupIDs, $childGroupIds);
+      }
+
+      // if $regularGroupIDs is populated with regular child group IDs
+      //   then change the mysql operator to desired
+      if (count($regularGroupIDs) > 1) {
+        $op = strpos($op, 'IN') ? $op : ($op == '!=') ? 'NOT IN' : 'IN';
+      }
       $groupIds = implode(',', (array) $regularGroupIDs);
       $gcTable = "`civicrm_group_contact-{$groupIds}`";
       $joinClause = array("contact_a.id = {$gcTable}.contact_id");
-      if ($statii) {
-        $joinClause[] = "{$gcTable}.status IN (" . implode(', ', $statii) . ")";
-      }
-      $this->_tables[$gcTable] = $this->_whereTables[$gcTable] = " LEFT JOIN civicrm_group_contact {$gcTable} ON (" . implode(' AND ', $joinClause) . ")";
+
       if (strpos($op, 'IN') !== FALSE) {
-        $clause = "{$gcTable}.group_id $op ( $groupIds ) %s ";
+        $clause = "{$gcTable}.group_id $op ( $groupIds ) ";
       }
       elseif ($op == '!=') {
-        $clause = "{$gcTable}.contact_id NOT IN (SELECT contact_id FROM civicrm_group_contact cgc WHERE cgc.group_id = $groupIds %s)";
+        $clause = "{$gcTable}.contact_id NOT IN (SELECT contact_id FROM civicrm_group_contact cgc WHERE cgc.group_id = $groupIds )";
       }
       else {
-        $clause = "{$gcTable}.group_id $op $groupIds %s ";
+        $clause = "{$gcTable}.group_id $op $groupIds ";
       }
+      $groupClause[] = "( {$clause} )";
 
-      // include child groups IDs if any
-      $childGroupIds = CRM_Contact_BAO_Group::getChildGroupIds($regularGroupIDs);
-      $childClause = '';
-      if (count($childGroupIds)) {
-        $gcTable = ($op == '!=') ? 'cgc' : $gcTable;
-        $childClause = " OR {$gcTable}.group_id IN (" . implode(',', $childGroupIds) . ") ";
+      if ($statii) {
+        $joinClause[] = "{$gcTable}.status IN (" . implode(', ', $statii) . ")";
       }
-      $groupClause[] = '(' . sprintf($clause, $childClause) . ')';
+      $this->_tables[$gcTable] = $this->_whereTables[$gcTable] = " LEFT JOIN civicrm_group_contact {$gcTable} ON (" . implode(' AND ', $joinClause) . ")";
     }
 
     //CRM-19589: contact(s) removed from a Smart Group, resides in civicrm_group_contact table
@@ -4385,8 +4396,9 @@ public static function apiQuery(
 
     $sql = "$select $from $where $having";
 
-    // add group by
-    if ($query->_useGroupBy) {
+    // add group by only when API action is not getcount
+    //  otherwise query fetches incorrect count
+    if ($query->_useGroupBy && !$count) {
       $sql .= self::getGroupByFromSelectColumns($query->_select, 'contact_a.id');
     }
     if (!empty($sort)) {
diff --git a/tests/phpunit/CRM/Contact/BAO/GroupContactTest.php b/tests/phpunit/CRM/Contact/BAO/GroupContactTest.php
index ca36c6d17606..3de4a6e18752 100644
--- a/tests/phpunit/CRM/Contact/BAO/GroupContactTest.php
+++ b/tests/phpunit/CRM/Contact/BAO/GroupContactTest.php
@@ -94,23 +94,45 @@ public function testGetGroupId() {
    */
   public function testContactSearchByParentGroup() {
     // create a parent group
-    $groupParams1 = array(
+    $parentGroup = $this->callAPISuccess('Group', 'create', array(
       'title' => 'Parent Group',
       'description' => 'Parent Group',
       'visibility' => 'User and User Admin Only',
       'is_active' => 1,
-    );
-    $parentGroup = $this->callAPISuccess('Group', 'create', $groupParams1);
+    ));
 
     // create a child group
-    $groupParams2 = array(
+    $childGroup = $this->callAPISuccess('Group', 'create', array(
       'title' => 'Child Group',
       'description' => 'Child Group',
       'visibility' => 'User and User Admin Only',
       'parents' => $parentGroup['id'],
       'is_active' => 1,
-    );
-    $childGroup = $this->callAPISuccess('Group', 'create', $groupParams2);
+    ));
+
+    // create smart group based on saved criteria Gender = Male
+    $batch = $this->callAPISuccess('SavedSearch', 'create', array(
+      'form_values' => 'a:1:{i:0;a:5:{i:0;s:9:"gender_id";i:1;s:1:"=";i:2;i:2;i:3;i:0;i:4;i:0;}}',
+    ));
+    // Create contact with Gender - Male
+    $childSmartGroupContact = $this->individualCreate(array(
+      'gender_id' => "Male",
+      'first_name' => 'C',
+    ), 1);
+    // then create smart group
+    $childSmartGroup = $this->callAPISuccess('Group', 'create', array(
+      'title' => 'Child Smart Group',
+      'description' => 'Child Smart Group',
+      'visibility' => 'User and User Admin Only',
+      'saved_search_id' => $batch['id'],
+      'is_active' => 1,
+      'parents' => $parentGroup['id'],
+    ));
+
+    $this->callAPISuccess('Group', 'create', array(
+      'id' => $parentGroup['id'],
+      'children' => implode(',', array($childGroup['id'], $childSmartGroup['id'])),
+    ));
 
     // Create a contact within parent group
     $parentContactParams = array(
@@ -129,23 +151,21 @@ public function testContactSearchByParentGroup() {
     $childContact = $this->individualCreate($childContactParams);
 
     // Check if searching by parent group  returns both parent and child group contacts
-    $searchParams = array(
+    $result = $this->callAPISuccess('contact', 'get', array(
       'group' => $parentGroup['id'],
-    );
-    $result = $this->callAPISuccess('contact', 'get', $searchParams);
+    ));
     $validContactIds = array($parentContact, $childContact);
     $resultContactIds = array();
     foreach ($result['values'] as $k => $v) {
       $resultContactIds[] = $v['contact_id'];
     }
-    $this->assertEquals(2, count($resultContactIds), 'Check the count of returned values');
+    $this->assertEquals(3, count($resultContactIds), 'Check the count of returned values');
     $this->assertEquals(array(), array_diff($validContactIds, $resultContactIds), 'Check that the difference between two arrays should be blank array');
 
     // Check if searching by child group returns just child group contacts
-    $searchParams = array(
+    $result = $this->callAPISuccess('contact', 'get', array(
       'group' => $childGroup['id'],
-    );
-    $result = $this->callAPISuccess('contact', 'get', $searchParams);
+    ));
     $validChildContactIds = array($childContact);
     $resultChildContactIds = array();
     foreach ($result['values'] as $k => $v) {
@@ -153,6 +173,23 @@ public function testContactSearchByParentGroup() {
     }
     $this->assertEquals(1, count($resultChildContactIds), 'Check the count of returned values');
     $this->assertEquals(array(), array_diff($validChildContactIds, $resultChildContactIds), 'Check that the difference between two arrays should be blank array');
+
+    // Check if searching by smart child group returns just smart child group contacts
+    $result = $this->callAPISuccess('contact', 'get', array(
+      'group' => $childSmartGroup['id'],
+    ));
+    $validChildContactIds = array($childSmartGroupContact);
+    $resultChildContactIds = array();
+    foreach ($result['values'] as $k => $v) {
+      $resultChildContactIds[] = $v['contact_id'];
+    }
+    $this->assertEquals(1, count($resultChildContactIds), 'Check the count of returned values');
+    $this->assertEquals(array(), array_diff($validChildContactIds, $resultChildContactIds), 'Check that the difference between two arrays should be blank array');
+
+    //cleanup
+    $this->callAPISuccess('Contact', 'delete', array('id' => $parentContact));
+    $this->callAPISuccess('Contact', 'delete', array('id' => $childContact));
+    $this->callAPISuccess('Contact', 'delete', array('id' => $childSmartGroupContact));
   }