diff --git a/tmux.1 b/tmux.1
index 11282404..bedf404b 100644
--- a/tmux.1
+++ b/tmux.1
@@ -1343,7 +1343,7 @@ was given to the
 .Ic set-environment
 command).
 The default is
-.Ev DISPLAY .
+"DISPLAY WINDOWID SSH_ASKPASS SSH_AUTH_SOCK SSH_AGENT_PID SSH_CONNECTION".
 .It Xo Ic visual-activity
 .Op Ic on | off
 .Xc
diff --git a/tmux.c b/tmux.c
index 4437f07b..eab2c2aa 100644
--- a/tmux.c
+++ b/tmux.c
@@ -381,7 +381,8 @@ main(int argc, char **argv)
 		options_set_number(&global_s_options, "status-utf8", 0);
 	options_set_string(&global_s_options,
 	    "terminal-overrides", "*88col*:colors=88,*256col*:colors=256");
-	options_set_string(&global_s_options, "update-environment", "DISPLAY");
+	options_set_string(&global_s_options, "update-environment", "DISPLAY "
+	    "WINDOWID SSH_ASKPASS SSH_AUTH_SOCK SSH_AGENT_PID SSH_CONNECTION");
 	options_set_number(&global_s_options, "visual-activity", 0);
 	options_set_number(&global_s_options, "visual-bell", 0);
 	options_set_number(&global_s_options, "visual-content", 0);