diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index c7a00f595..4483bdd6f 100644
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -8970,7 +8970,7 @@ inline void gcode_M503() {
     SERIAL_ECHOPAIR("Advance K=", planner.extruder_advance_k);
     SERIAL_ECHOPGM(" E/D=");
     const float ratio = planner.advance_ed_ratio;
-    ratio ? SERIAL_ECHO(ratio) : SERIAL_ECHOPGM("Auto");
+    if (ratio) SERIAL_ECHO(ratio); else SERIAL_ECHOPGM("Auto");
     SERIAL_EOL;
   }
 #endif // LIN_ADVANCE