diff --git a/modules/mcuboot/boot/zephyr/Kconfig b/modules/mcuboot/boot/zephyr/Kconfig
index d4752cf04c1a..e1f8d8884f34 100644
--- a/modules/mcuboot/boot/zephyr/Kconfig
+++ b/modules/mcuboot/boot/zephyr/Kconfig
@@ -39,6 +39,7 @@ config PM_PARTITION_SIZE_MCUBOOT
 	hex "Flash space allocated for the MCUboot partition" if !BOOT_USE_MIN_PARTITION_SIZE
 	default 0xb800 if MCUBOOT_MCUBOOT_IMAGE_NUMBER != -1 && SOC_SERIES_NRF54LX
 	default 0xbe00 if MCUBOOT_MCUBOOT_IMAGE_NUMBER != -1 && !SOC_SERIES_NRF54LX
+	default 0xd000 if SOC_SERIES_NRF54LX && BOOT_SIGNATURE_TYPE_ED25519 && !BOOT_SIGNATURE_USING_KMU
 	default 0xc000
 	help
 	  Flash space set aside for the MCUboot partition.
diff --git a/sysbuild/Kconfig.mcuboot b/sysbuild/Kconfig.mcuboot
index b72c2043b69d..675a710780d8 100644
--- a/sysbuild/Kconfig.mcuboot
+++ b/sysbuild/Kconfig.mcuboot
@@ -139,6 +139,7 @@ choice BOOT_SIGNATURE_TYPE
 	default BOOT_SIGNATURE_TYPE_RSA if THINGY91_STATIC_PARTITIONS_FACTORY
 	default BOOT_SIGNATURE_TYPE_ECDSA_P256 if ((SOC_NRF52840 || SOC_SERIES_NRF91X) && !BOARD_THINGY91_NRF9160 && !BOARD_THINGY91_NRF52840)
 	default BOOT_SIGNATURE_TYPE_ECDSA_P256 if SECURE_BOOT_APPCORE
+	default BOOT_SIGNATURE_TYPE_ED25519 if SOC_SERIES_NRF54LX
 
 endchoice