diff --git a/toxav/toxav.h b/toxav/toxav.h
index 4615a0a0..c019bfb4 100644
--- a/toxav/toxav.h
+++ b/toxav/toxav.h
@@ -315,6 +315,11 @@ bool toxav_answer(ToxAV *av, uint32_t friend_number, uint32_t audio_bit_rate, ui
 
 enum TOXAV_FRIEND_CALL_STATE {
 
+    /**
+     * The empty bit mask. None of the bits specified below are set.
+     */
+    TOXAV_FRIEND_CALL_STATE_NONE = 0,
+
     /**
      * Set by the AV core if an error occurred on the remote end or if friend
      * timed out. This is the final state after which no more state