diff --git a/system/HTTP/IncomingRequest.php b/system/HTTP/IncomingRequest.php
index 12fb1887e7d6..b7c04dfba89a 100755
--- a/system/HTTP/IncomingRequest.php
+++ b/system/HTTP/IncomingRequest.php
@@ -427,7 +427,7 @@ public function getPostGet($index = null, $filter = null, $flags = null)
 		// Use $_POST directly here, since filter_has_var only
 		// checks the initial POST data, not anything that might
 		// have been added since.
-		return isset($_POST[$index]) ? $this->getPost($index, $filter, $flags) : $this->getGet($index, $filter, $flags);
+		return isset($_POST[$index]) ? $this->getPost($index, $filter, $flags) : (isset($_GET[$index]) ? $this->getGet($index, $filter, $flags) : $this->getPost());
 	}
 
 	//--------------------------------------------------------------------
@@ -446,7 +446,7 @@ public function getGetPost($index = null, $filter = null, $flags = null)
 		// Use $_GET directly here, since filter_has_var only
 		// checks the initial GET data, not anything that might
 		// have been added since.
-		return isset($_GET[$index]) ? $this->getGet($index, $filter, $flags) : $this->getPost($index, $filter, $flags);
+		return isset($_GET[$index]) ? $this->getGet($index, $filter, $flags) : (isset($_POST[$index]) ? $this->getPost($index, $filter, $flags) : $this->getGet());
 	}
 
 	//--------------------------------------------------------------------
diff --git a/tests/system/HTTP/IncomingRequestTest.php b/tests/system/HTTP/IncomingRequestTest.php
index 9f748ba5e223..6457f92da6a6 100644
--- a/tests/system/HTTP/IncomingRequestTest.php
+++ b/tests/system/HTTP/IncomingRequestTest.php
@@ -423,4 +423,15 @@ public function testSpoofing()
 		$this->assertEquals('wink', $this->request->getMethod());
 	}
 
+	/**
+	 * @see https://github.com/codeigniter4/CodeIgniter4/issues/2839
+	 */
+	public function testGetPostEmpty()
+	{
+		$_POST['TEST'] = 5;
+		$_GET['TEST']  = 3;
+		$this->assertEquals($_POST, $this->request->getPostGet());
+		$this->assertEquals($_GET, $this->request->getGetPost());
+	}
+
 }