diff --git a/src/buffer.c b/src/buffer.c
index 1564674d86d..7af8dbc334c 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -5302,7 +5302,8 @@ nil here means use current buffer's major mode.  */);
 
   DEFVAR_PER_BUFFER ("fill-column", &current_buffer->fill_column,
 		     make_number (Lisp_Int),
-		     doc: /* *Column beyond which automatic line-wrapping should happen.  */);
+		     doc: /* *Column beyond which automatic line-wrapping should happen.
+Interactively, you can set this using \\[set-fill-column].  */);
 
   DEFVAR_PER_BUFFER ("left-margin", &current_buffer->left_margin,
 		     make_number (Lisp_Int),