diff --git a/keyboards/zinc/keymaps/default/rules.mk b/keyboards/zinc/keymaps/default/rules.mk
index 883f0fc603..5cdd1c81aa 100644
--- a/keyboards/zinc/keymaps/default/rules.mk
+++ b/keyboards/zinc/keymaps/default/rules.mk
@@ -14,6 +14,7 @@ AUDIO_ENABLE = no           # Audio output
 UNICODE_ENABLE = no         # Unicode
 RGBLIGHT_ENABLE = no        # Enable WS2812 RGB underlight.  Do not enable this with audio at the same time.
 SWAP_HANDS_ENABLE = no        # Enable one-hand typing
+LTO_ENABLE = no             # if firmware size over limit, try this option
 
 define ZINC_CUSTOMISE_MSG
   $(info Zinc customize)
@@ -35,7 +36,6 @@ RGB_MATRIX = no             # RGB LED Matrix
 RGB_MATRIX_SPLIT_RIGHT = no # RGB Matrix for RIGHT Hand
 LED_ANIMATIONS = yes        # LED animations
 IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-Link_Time_Optimization = no # if firmware size over limit, try this option
 
 ####  LED_BACK_ENABLE and LED_UNDERGLOW_ENABLE.
 ####    Do not enable these with audio at the same time.
@@ -121,10 +121,6 @@ ifeq ($(strip $(RGB_MATRIX_SPLIT_RIGHT)), yes)
     OPT_DEFS += -DRGB_MATRIX_SPLIT_RIGHT
 endif
 
-ifeq ($(strip $(Link_Time_Optimization)),yes)
-  EXTRAFLAGS += -flto -DUSE_Link_Time_Optimization
-endif
-
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
 
diff --git a/keyboards/zinc/keymaps/ginjake/rules.mk b/keyboards/zinc/keymaps/ginjake/rules.mk
index 63e5227ef9..f2cb3633c6 100644
--- a/keyboards/zinc/keymaps/ginjake/rules.mk
+++ b/keyboards/zinc/keymaps/ginjake/rules.mk
@@ -15,6 +15,7 @@ UNICODE_ENABLE = no         # Unicode
 BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
 RGBLIGHT_ENABLE = no        # Enable WS2812 RGB underlight.  Do not enable this with audio at the same time.
 SWAP_HANDS_ENABLE = no        # Enable one-hand typing
+LTO_ENABLE = no             # if firmware size over limit, try this option
 
 define ZINC_CUSTOMISE_MSG
   $(info Zinc customize)
@@ -33,7 +34,6 @@ LED_BOTH_ENABLE = no        # LED backlight and underglow
 LED_RGB_CONT = no           # LED continuous backlight or/and underglow between left Zinc and right Zinc
 LED_ANIMATIONS = yes        # LED animations
 IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-Link_Time_Optimization = no # if firmware size over limit, try this option
 
 ####  LED_BACK_ENABLE and LED_UNDERGLOW_ENABLE.
 ####    Do not enable these with audio at the same time.
@@ -104,10 +104,6 @@ ifeq ($(strip $(LED_ANIMATIONS)), yes)
 
 endif
 
-ifeq ($(strip $(Link_Time_Optimization)),yes)
-  EXTRAFLAGS += -flto -DUSE_Link_Time_Optimization
-endif
-
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
 
diff --git a/keyboards/zinc/keymaps/monks/rules.mk b/keyboards/zinc/keymaps/monks/rules.mk
index d8ec4497e7..46646f919c 100644
--- a/keyboards/zinc/keymaps/monks/rules.mk
+++ b/keyboards/zinc/keymaps/monks/rules.mk
@@ -15,6 +15,7 @@ UNICODE_ENABLE = no         # Unicode
 BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
 RGBLIGHT_ENABLE = no        # Enable WS2812 RGB underlight.  Do not enable this with audio at the same time.
 SWAP_HANDS_ENABLE = no        # Enable one-hand typing
+LTO_ENABLE = no             # if firmware size over limit, try this option
 
 define ZINC_CUSTOMISE_MSG
   $(info Zinc customize)
@@ -33,7 +34,6 @@ LED_BOTH_ENABLE = no        # LED backlight and underglow
 LED_RGB_CONT = no           # LED continuous backlight or/and underglow between left Zinc and right Zinc
 LED_ANIMATIONS = yes        # LED animations
 IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-Link_Time_Optimization = no # if firmware size over limit, try this option
 
 ####  LED_BACK_ENABLE and LED_UNDERGLOW_ENABLE.
 ####    Do not enable these with audio at the same time.
@@ -104,10 +104,6 @@ ifeq ($(strip $(LED_ANIMATIONS)), yes)
 
 endif
 
-ifeq ($(strip $(Link_Time_Optimization)),yes)
-  EXTRAFLAGS += -flto -DUSE_Link_Time_Optimization
-endif
-
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
 
diff --git a/keyboards/zinc/keymaps/toshi0383/rules.mk b/keyboards/zinc/keymaps/toshi0383/rules.mk
index 7860cbd019..9fef6963a1 100644
--- a/keyboards/zinc/keymaps/toshi0383/rules.mk
+++ b/keyboards/zinc/keymaps/toshi0383/rules.mk
@@ -15,6 +15,7 @@ UNICODE_ENABLE = no         # Unicode
 BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
 RGBLIGHT_ENABLE = no        # Enable WS2812 RGB underlight.  Do not enable this with audio at the same time.
 SWAP_HANDS_ENABLE = no      # Enable one-hand typing
+LTO_ENABLE = no             # if firmware size over limit, try this option
 
 define ZINC_CUSTOMISE_MSG
   $(info Zinc customize)
@@ -36,7 +37,6 @@ RGB_MATRIX = no             # RGB LED Matrix
 RGB_MATRIX_SPLIT_RIGHT = no # RGB Matrix for RIGHT Hand
 LED_ANIMATIONS = yes        # LED animations
 IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-Link_Time_Optimization = no # if firmware size over limit, try this option
 
 ####  LED_BACK_ENABLE and LED_UNDERGLOW_ENABLE.
 ####    Do not enable these with audio at the same time.
@@ -122,10 +122,6 @@ ifeq ($(strip $(RGB_MATRIX_SPLIT_RIGHT)), yes)
     OPT_DEFS += -DRGB_MATRIX_SPLIT_RIGHT
 endif
 
-ifeq ($(strip $(Link_Time_Optimization)),yes)
-  EXTRAFLAGS += -flto -DUSE_Link_Time_Optimization
-endif
-
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend