diff --git a/data/start-cosmic b/data/start-cosmic
index 6e05738..a947e16 100755
--- a/data/start-cosmic
+++ b/data/start-cosmic
@@ -38,6 +38,19 @@ export QT_AUTO_SCREEN_SCALE_FACTOR=1
 export QT_ENABLE_HIGHDPI_SCALING=1
 export DCONF_PROFILE=cosmic
 
+# Set the QT platform theme to CuteCosmic. Fallback to qt6ct if CuteCosmic is not installed.
+export QT_QPA_PLATFORMTHEME=cosmic
+for QT_PLUGIN_PATH in /usr/lib{*,/*}/qt6/plugins; do
+    if [ -f "${QT_PLUGIN_PATH}/platformthemes/libcutecosmictheme.so" ]; then
+        # CuteCosmic found, no need for a fallback.
+        export QT_QPA_PLATFORMTHEME=cosmic
+        break
+    elif [ -f "${QT_PLUGIN_PATH}/platformthemes/libqt6ct.so" ]; then
+        # Fallback to qt6ct, but keep looking for CuteCosmic.
+        export QT_QPA_PLATFORMTHEME=qt6ct
+    fi
+done
+
 # Start gnome keyring components if the daemon is active
 # -> check if /run/user/$UID/keyring exists
 if [ -d "/run/user/$(id -u)/keyring" ]; then