diff --git a/library/CM/Log/Handler/MongoDb.php b/library/CM/Log/Handler/MongoDb.php
index 6d37c77f0..e47fff897 100644
--- a/library/CM/Log/Handler/MongoDb.php
+++ b/library/CM/Log/Handler/MongoDb.php
@@ -84,6 +84,10 @@ protected function _formatRecord(CM_Log_Record $record) {
                 'server'  => $request->getServer(),
                 'headers' => $request->getHeaders(),
             ];
+
+            if ($request->hasClientId()) {
+                $formattedContext['httpRequest']['clientId'] = $request->getClientId();
+            }
         }
 
         return [
diff --git a/tests/library/CM/Log/Handler/MongoDbTest.php b/tests/library/CM/Log/Handler/MongoDbTest.php
index 58a4b477a..175a652d0 100644
--- a/tests/library/CM/Log/Handler/MongoDbTest.php
+++ b/tests/library/CM/Log/Handler/MongoDbTest.php
@@ -34,6 +34,7 @@ public function testWriting() {
         $ttl = 30;
         $user = CMTest_TH::createUser();
         $httpRequest = CM_Http_Request_Abstract::factory('post', '/foo?bar=1&baz=quux', ['bar' => 'baz'], ['foo' => 'quux'], '{"bar":"2", "quux":"baz"}');
+        $clientId = $httpRequest->getClientId();
         $computerInfo = new CM_Log_Context_ComputerInfo('www.example.com', 'v7.0.1');
 
         $mongoClient = $this->getServiceManager()->getMongoDb();
@@ -68,6 +69,7 @@ public function testWriting() {
         $this->assertSame(['bar' => '2', 'baz' => 'quux', 'quux' => 'baz'], $context['httpRequest']['query']);
         $this->assertSame(['bar' => 'baz'], $context['httpRequest']['headers']);
         $this->assertSame(['foo' => 'quux'], $context['httpRequest']['server']);
+        $this->assertSame($clientId, $context['httpRequest']['clientId']);
         $this->assertSame('www.example.com', $context['computerInfo']['fqdn']);
         $this->assertSame('v7.0.1', $context['computerInfo']['phpVersion']);
         $this->assertSame(['bar' => ['baz' => 'quux']], $context['extra']);