diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/Kconfig.board b/boards/boards_legacy/arm/b_l4s5i_iot01a/Kconfig.board
deleted file mode 100644
index 927b683f71e..00000000000
--- a/boards/boards_legacy/arm/b_l4s5i_iot01a/Kconfig.board
+++ /dev/null
@@ -1,8 +0,0 @@
-# B_L4S5I_IOT01A discovery kit configuration
-
-# Copyright (c) 2020 STMicroelectronics
-# SPDX-License-Identifier: Apache-2.0
-
-config BOARD_B_L4S5I_IOT01A
-	bool "STM32L4S5I IOT Discovery kit"
-	depends on SOC_STM32L4S5XX
diff --git a/boards/st/b_l4s5i_iot01a/Kconfig.b_l4s5i_iot01a b/boards/st/b_l4s5i_iot01a/Kconfig.b_l4s5i_iot01a
new file mode 100644
index 00000000000..e4c8a21a27a
--- /dev/null
+++ b/boards/st/b_l4s5i_iot01a/Kconfig.b_l4s5i_iot01a
@@ -0,0 +1,5 @@
+# Copyright (c) 2020 STMicroelectronics
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_B_L4S5I_IOT01A
+	select SOC_STM32L4S5XX
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/Kconfig.defconfig b/boards/st/b_l4s5i_iot01a/Kconfig.defconfig
similarity index 94%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/Kconfig.defconfig
rename to boards/st/b_l4s5i_iot01a/Kconfig.defconfig
index 059f36907a2..36b722dbf38 100644
--- a/boards/boards_legacy/arm/b_l4s5i_iot01a/Kconfig.defconfig
+++ b/boards/st/b_l4s5i_iot01a/Kconfig.defconfig
@@ -5,9 +5,6 @@
 
 if BOARD_B_L4S5I_IOT01A
 
-config BOARD
-	default "b_l4s5i_iot01a"
-
 config SPI_STM32_INTERRUPT
 	default y
 	depends on SPI
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/arduino_r3_connector.dtsi b/boards/st/b_l4s5i_iot01a/arduino_r3_connector.dtsi
similarity index 100%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/arduino_r3_connector.dtsi
rename to boards/st/b_l4s5i_iot01a/arduino_r3_connector.dtsi
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/b_l4s5i_iot01a.dts b/boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a.dts
similarity index 100%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/b_l4s5i_iot01a.dts
rename to boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a.dts
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/b_l4s5i_iot01a.yaml b/boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a.yaml
similarity index 100%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/b_l4s5i_iot01a.yaml
rename to boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a.yaml
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig b/boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig
similarity index 81%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig
rename to boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig
index 981dd5f1670..9e3dfce576e 100644
--- a/boards/boards_legacy/arm/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig
+++ b/boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig
@@ -1,8 +1,5 @@
 # SPDX-License-Identifier: Apache-2.0
 
-CONFIG_SOC_SERIES_STM32L4X=y
-CONFIG_SOC_STM32L4S5XX=y
-
 # enable uart driver
 CONFIG_SERIAL=y
 
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/board.cmake b/boards/st/b_l4s5i_iot01a/board.cmake
similarity index 100%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/board.cmake
rename to boards/st/b_l4s5i_iot01a/board.cmake
diff --git a/boards/st/b_l4s5i_iot01a/board.yml b/boards/st/b_l4s5i_iot01a/board.yml
new file mode 100644
index 00000000000..e41cb4b1002
--- /dev/null
+++ b/boards/st/b_l4s5i_iot01a/board.yml
@@ -0,0 +1,5 @@
+board:
+  name: b_l4s5i_iot01a
+  vendor: st
+  socs:
+    - name: stm32l4s5xx
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/doc/img/b-l4s5i_iot01a.jpg b/boards/st/b_l4s5i_iot01a/doc/img/b-l4s5i_iot01a.jpg
similarity index 100%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/doc/img/b-l4s5i_iot01a.jpg
rename to boards/st/b_l4s5i_iot01a/doc/img/b-l4s5i_iot01a.jpg
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/doc/index.rst b/boards/st/b_l4s5i_iot01a/doc/index.rst
similarity index 99%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/doc/index.rst
rename to boards/st/b_l4s5i_iot01a/doc/index.rst
index d5b11c8b30b..3cceb1109fc 100644
--- a/boards/boards_legacy/arm/b_l4s5i_iot01a/doc/index.rst
+++ b/boards/st/b_l4s5i_iot01a/doc/index.rst
@@ -135,7 +135,7 @@ The Zephyr b_l4s5i_iot01a board configuration supports the following hardware fe
 
 The default configuration can be found in the defconfig file:
 
-	``boards/arm/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig``
+	``boards/st/b_l4s5i_iot01a/b_l4s5i_iot01a_defconfig``
 
 
 Connections and IOs
diff --git a/boards/boards_legacy/arm/b_l4s5i_iot01a/support/openocd.cfg b/boards/st/b_l4s5i_iot01a/support/openocd.cfg
similarity index 100%
rename from boards/boards_legacy/arm/b_l4s5i_iot01a/support/openocd.cfg
rename to boards/st/b_l4s5i_iot01a/support/openocd.cfg