diff --git a/man/tio.1 b/man/tio.1
index cdb0295..c4eeac0 100644
--- a/man/tio.1
+++ b/man/tio.1
@@ -56,6 +56,11 @@ option is provided, tio will exit if the device is not present or an established
 
 Enable local echo.
 
+.TP
+.BR \-t ", " \-\-timestamp
+
+Prefix each new line with a timestamp.
+
 .TP
 .BR \-l ", " "\-\-log " \fI<filename>