diff --git a/plugins/tmux/tmux.plugin.zsh b/plugins/tmux/tmux.plugin.zsh
index 08cf3c7a5..c501ad701 100644
--- a/plugins/tmux/tmux.plugin.zsh
+++ b/plugins/tmux/tmux.plugin.zsh
@@ -88,7 +88,7 @@ _build_tmux_alias "tkss" "kill-session" "-t"
 unfunction _build_tmux_alias
 
 # Determine if the terminal supports at least 256 colors
-if [[ $terminfo[colors] -ge 256 ]]; then
+if (( ${+terminfo[colors]} )) && [[ $terminfo[colors] -ge 256 ]]; then
   export ZSH_TMUX_TERM=$ZSH_TMUX_FIXTERM_WITH_256COLOR
 else
   export ZSH_TMUX_TERM=$ZSH_TMUX_FIXTERM_WITHOUT_256COLOR