diff --git a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h
index fb1218068eb3..a38be0bef765 100644
--- a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h
+++ b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h
@@ -151,7 +151,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h
index 49c4dffa04ed..ce1372ed7a94 100644
--- a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h
+++ b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h
@@ -174,7 +174,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h b/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h
index 23558b2e0474..59d6a06cf423 100644
--- a/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h
+++ b/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h
@@ -153,7 +153,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h b/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h
index d112cc5d5080..2d09fe1feae5 100644
--- a/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h
+++ b/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h
@@ -163,7 +163,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_NANO_V2.h b/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_NANO_V2.h
index 01415d7bf0e2..d911ab2b517b 100644
--- a/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_NANO_V2.h
+++ b/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_NANO_V2.h
@@ -132,7 +132,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_PRO.h b/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_PRO.h
index c00466677a25..9b3817df8c7b 100644
--- a/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_PRO.h
+++ b/Marlin/src/pins/stm32f1/pins_MKS_ROBIN_PRO.h
@@ -125,7 +125,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/stm32f4/pins_BTT_GTR_V1_0.h b/Marlin/src/pins/stm32f4/pins_BTT_GTR_V1_0.h
index 55d1a37aa7f7..8cc1ca5e98b2 100644
--- a/Marlin/src/pins/stm32f4/pins_BTT_GTR_V1_0.h
+++ b/Marlin/src/pins/stm32f4/pins_BTT_GTR_V1_0.h
@@ -171,7 +171,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/stm32f4/pins_BTT_SKR_PRO_common.h b/Marlin/src/pins/stm32f4/pins_BTT_SKR_PRO_common.h
index 9e6a43c36b9a..b45914284adf 100644
--- a/Marlin/src/pins/stm32f4/pins_BTT_SKR_PRO_common.h
+++ b/Marlin/src/pins/stm32f4/pins_BTT_SKR_PRO_common.h
@@ -178,7 +178,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1
diff --git a/Marlin/src/pins/stm32f4/pins_RUMBA32_MKS.h b/Marlin/src/pins/stm32f4/pins_RUMBA32_MKS.h
index fe6e559bdb8e..ab277d43722a 100644
--- a/Marlin/src/pins/stm32f4/pins_RUMBA32_MKS.h
+++ b/Marlin/src/pins/stm32f4/pins_RUMBA32_MKS.h
@@ -57,7 +57,7 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial
+  //#define X_HARDWARE_SERIAL  Serial1
   //#define X2_HARDWARE_SERIAL Serial1
   //#define Y_HARDWARE_SERIAL  Serial1
   //#define Y2_HARDWARE_SERIAL Serial1