diff --git a/Classes/Domain/Factory/FileFactory.php b/Classes/Domain/Factory/FileFactory.php
index 999ce37fe..8d4bcacd6 100644
--- a/Classes/Domain/Factory/FileFactory.php
+++ b/Classes/Domain/Factory/FileFactory.php
@@ -105,7 +105,9 @@ protected function makeFileInstance(
         $file->setNewName(StringUtility::cleanString($originalName));
         $file->setUploadFolder($this->getUploadFolder());
         if ($size === 0) {
-            $size = (int)filesize($file->getNewPathAndFilename(true));
+            $size = (int)filesize(
+                $uploaded ? $file->getNewPathAndFilename(true) : $file->getTemporaryName()
+            );
         }
 
         $file->setSize($size);