diff --git a/boot/zephyr/boards/nrf54l15pdk_nrf54l15_cpuapp_ext_flash.conf b/boot/zephyr/boards/nrf54l15pdk_nrf54l15_cpuapp_ext_flash.conf
new file mode 100644
index 000000000..841922dbd
--- /dev/null
+++ b/boot/zephyr/boards/nrf54l15pdk_nrf54l15_cpuapp_ext_flash.conf
@@ -0,0 +1,8 @@
+CONFIG_MULTITHREADING=y
+CONFIG_SPI=y
+CONFIG_SPI_NOR=y
+CONFIG_FLASH=y
+CONFIG_PM_PARTITION_SIZE_MCUBOOT=0x14000
+CONFIG_MAIN_STACK_SIZE=20480
+CONFIG_BOOT_MAX_IMG_SECTORS=512
+CONFIG_SPI_NOR_FLASH_LAYOUT_PAGE_SIZE=4096
diff --git a/boot/zephyr/boards/nrf54l15pdk_nrf54l15_cpuapp_ext_flash.overlay b/boot/zephyr/boards/nrf54l15pdk_nrf54l15_cpuapp_ext_flash.overlay
new file mode 100644
index 000000000..2341ffd26
--- /dev/null
+++ b/boot/zephyr/boards/nrf54l15pdk_nrf54l15_cpuapp_ext_flash.overlay
@@ -0,0 +1,10 @@
+/ {
+	chosen {
+		nordic,pm-ext-flash = &mx25r64;
+	};
+};
+
+
+&mx25r64 {
+	status = "okay";
+};