diff --git a/system/Database/BaseConnection.php b/system/Database/BaseConnection.php
index 5f678e5114d7..53e5dad1b351 100644
--- a/system/Database/BaseConnection.php
+++ b/system/Database/BaseConnection.php
@@ -258,14 +258,14 @@ abstract class BaseConnection implements ConnectionInterface
      *
      * @var float
      */
-    protected $connectTime;
+    protected $connectTime = 0.0;
 
     /**
      * How long it took to establish connection.
      *
      * @var float
      */
-    protected $connectDuration;
+    protected $connectDuration = 0.0;
 
     /**
      * If true, no queries will actually be
diff --git a/tests/system/Database/BaseConnectionTest.php b/tests/system/Database/BaseConnectionTest.php
index 7d2352a0e9b2..9bb8ddee1499 100644
--- a/tests/system/Database/BaseConnectionTest.php
+++ b/tests/system/Database/BaseConnectionTest.php
@@ -123,6 +123,16 @@ public function testStoresConnectionTimings()
         $this->assertGreaterThan(0.0, $db->getConnectDuration());
     }
 
+    /**
+     * @see https://github.com/codeigniter4/CodeIgniter4/issues/5535
+     */
+    public function testStoresConnectionTimingsNotConnected()
+    {
+        $db = new MockConnection($this->options);
+
+        $this->assertSame('0.000000', $db->getConnectDuration());
+    }
+
     public function testMagicIssetTrue()
     {
         $db = new MockConnection($this->options);