diff --git a/boards/native/native_sim/Kconfig b/boards/native/native_sim/Kconfig
index fc84adda149..1e79e7409d6 100644
--- a/boards/native/native_sim/Kconfig
+++ b/boards/native/native_sim/Kconfig
@@ -45,6 +45,7 @@ config BOARD_NATIVE_POSIX
 config NATIVE_POSIX_SLOWDOWN_TO_REAL_TIME
 	bool "Slow down execution to real time (native_posix compat)"
 	select NATIVE_SIM_SLOWDOWN_TO_REAL_TIME
+	select DEPRECATED
 	help
 	  Transitional option which allows applications which targeted native_posix
 	  to set the correct native_sim option (CONFIG_NATIVE_SIM_SLOWDOWN_TO_REAL_TIME)