diff --git a/arch/arm/src/stm32/Kconfig b/arch/arm/src/stm32/Kconfig
index 22564254cf8..d1098add85f 100644
--- a/arch/arm/src/stm32/Kconfig
+++ b/arch/arm/src/stm32/Kconfig
@@ -2488,6 +2488,7 @@ config STM32_RTC
 	bool "RTC"
 	default n
 	select RTC
+	depends on !RTC_EXTERNAL
 
 config STM32_USBHOST
 	bool
diff --git a/arch/arm/src/stm32f7/Kconfig b/arch/arm/src/stm32f7/Kconfig
index 9bcb24df6d4..ca9ae596bb6 100644
--- a/arch/arm/src/stm32f7/Kconfig
+++ b/arch/arm/src/stm32f7/Kconfig
@@ -1426,6 +1426,7 @@ config STM32F7_RTC
 	bool "RTC"
 	default n
 	select RTC
+	depends on !RTC_EXTERNAL
 
 config STM32F7_PWR
 	bool "PWR"
diff --git a/arch/arm/src/stm32l4/Kconfig b/arch/arm/src/stm32l4/Kconfig
index 68bf1845afd..d3dde3b4eda 100644
--- a/arch/arm/src/stm32l4/Kconfig
+++ b/arch/arm/src/stm32l4/Kconfig
@@ -805,6 +805,7 @@ config STM32L4_RTC
 	bool "RTC"
 	default n
 	select RTC
+	depends on !RTC_EXTERNAL
 
 config STM32L4_HAVE_SDMMC1
 	bool