diff --git a/Marlin/src/pins/stm32f1/pins_BTT_SKR_CR6.h b/Marlin/src/pins/stm32f1/pins_BTT_SKR_CR6.h
index c614a2dbb9..f58f13dc2f 100644
--- a/Marlin/src/pins/stm32f1/pins_BTT_SKR_CR6.h
+++ b/Marlin/src/pins/stm32f1/pins_BTT_SKR_CR6.h
@@ -165,6 +165,7 @@
 #if SD_CONNECTION_IS(ONBOARD)
   #define SD_DETECT_PIN                     PC4
   #define ONBOARD_SD_CS_PIN                 PA4   // Chip select for "System" SD card
+  #define SDSS                              ONBOARD_SD_CS_PIN
 #endif
 
 //