diff --git a/moviepy/video/VideoClip.py b/moviepy/video/VideoClip.py
index bda751018..1fca68ba7 100644
--- a/moviepy/video/VideoClip.py
+++ b/moviepy/video/VideoClip.py
@@ -218,6 +218,7 @@ def write_videofile(
         ffmpeg_params=None,
         logger="bar",
         pixel_format=None,
+        with_mask=False,
     ):
         """Write the clip to a videofile.
 
@@ -314,6 +315,9 @@ def write_videofile(
         pixel_format
           Pixel format for the output video file.
 
+        with_mask
+          Set to ``True`` if there is a mask in the video to be encoded.
+
         Examples
         --------
 
@@ -390,6 +394,7 @@ def write_videofile(
             ffmpeg_params=ffmpeg_params,
             logger=logger,
             pixel_format=pixel_format,
+            with_mask=with_mask
         )
 
         if remove_temp and make_audio: