diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index 7981b26209..6489b357fa 100644
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -9327,6 +9327,14 @@ inline void gcode_M221() {
     planner.flow_percentage[target_extruder] = parser.value_int();
     planner.refresh_e_factor(target_extruder);
   }
+  else {
+    SERIAL_ECHO_START();
+    SERIAL_CHAR('E');
+    SERIAL_CHAR('0' + target_extruder);
+    SERIAL_ECHOPAIR(" Flow: ", planner.flow_percentage[target_extruder]);
+    SERIAL_CHAR('%');
+    SERIAL_EOL();
+  }
 }
 
 /**