diff --git a/boards/nxp/frdm_mcxa156/Kconfig.defconfig b/boards/nxp/frdm_mcxa156/Kconfig.defconfig
deleted file mode 100644
index 117b55f95e843..0000000000000
--- a/boards/nxp/frdm_mcxa156/Kconfig.defconfig
+++ /dev/null
@@ -1,15 +0,0 @@
-# FRDM-MCXA156 board
-
-# Copyright 2024 NXP
-# SPDX-License-Identifier: Apache-2.0
-
-if BOARD_FRDM_MCXA156
-
-if BOOTLOADER_MCUBOOT
-choice MCUBOOT_BOOTLOADER_MODE
-	# Board only supports MCUBoot via "upgrade only" method:
-	default MCUBOOT_BOOTLOADER_MODE_OVERWRITE_ONLY
-endchoice
-endif #BOOTLOADER_MCUBOOT
-
-endif # BOARD_FRDM_MCXA156
diff --git a/boards/nxp/frdm_mcxa156/Kconfig.sysbuild b/boards/nxp/frdm_mcxa156/Kconfig.sysbuild
deleted file mode 100644
index 4625c7d2929d2..0000000000000
--- a/boards/nxp/frdm_mcxa156/Kconfig.sysbuild
+++ /dev/null
@@ -1,6 +0,0 @@
-# Copyright 2024 NXP
-# SPDX-License-Identifier: Apache-2.0
-
-choice MCUBOOT_MODE
-	default MCUBOOT_MODE_OVERWRITE_ONLY
-endchoice