diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index 90eb6e0357..9d7d6b15ef 100644
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -2006,7 +2006,7 @@ static void clean_up_after_endstop_or_probe_move() {
   //   - Raise to the BETWEEN height
   // - Return the probed Z position
   //
-  static float probe_pt(float x, float y, bool stow = true, int verbose_level = 1) {
+  static float probe_pt(const float &x, const float &y, bool stow = true, int verbose_level = 1) {
     #if ENABLED(DEBUG_LEVELING_FEATURE)
       if (DEBUGGING(LEVELING)) {
         SERIAL_ECHOPAIR(">>> probe_pt(", x);