diff --git a/panels/zcalibrate.py b/panels/zcalibrate.py
index 5dd84dcf..d072f86b 100644
--- a/panels/zcalibrate.py
+++ b/panels/zcalibrate.py
@@ -135,6 +135,7 @@ class ZCalibratePanel(ScreenPanel):
         self.labels['popover'].show_all()
 
     def start_calibration(self, widget, method):
+        x_position = y_position = 0
         self.labels['popover'].popdown()
         if self._screen.printer.get_stat("toolhead", "homed_axes") != "xyz":
             self._screen._ws.klippy.gcode_script(KlippyGcodes.HOME)