diff --git a/documentation/migration-guides/migration-6.0.rst b/documentation/migration-guides/migration-6.0.rst
index 15dbd08a0..16046dad8 100644
--- a/documentation/migration-guides/migration-6.0.rst
+++ b/documentation/migration-guides/migration-6.0.rst
@@ -189,6 +189,36 @@ class, meaning recipes using these variables that not yet inheriting the
 
 See commit :oecore_rev:`68d2d38483efada7bc2409e10508b03a7431caff` for more information.
 
+
+.. _ref-migration-6-0-wic-sector-size-change:
+
+:term:`WIC_SECTOR_SIZE` should be replaced by ``--sector-size``
+---------------------------------------------------------------
+
+The :term:`WIC_SECTOR_SIZE` variable was previously used to define the sector
+size of the partitions generated by the :doc:`WIC </dev-manual/wic>` tool. The
+``wic`` command-line tool now supports a ``--sector-size`` argument that
+replaces this variable.
+
+While this variable can still be used in recipes, a warning is now printed on
+the console when used::
+
+   DEPRECATED: WIC_SECTOR_SIZE is deprecated, use the --sector-size command-line argument instead.
+
+Using the ``--sector-size`` command-line argument can be done through the
+:term:`WIC_CREATE_EXTRA_ARGS` variable.
+
+For example, a previous assignment to :term:`WIC_SECTOR_SIZE`::
+
+   WIC_SECTOR_SIZE = "4096"
+
+Should be replaced by::
+
+   WIC_CREATE_EXTRA_ARGS += "--sector-size 4096"
+
+See commit :oecore_rev:`b50d6debf7baa555fbfb3521c4f952675bba2d37` for more
+information.
+
 Rust language changes
 ---------------------
 
diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst
index 89a5e632b..b698e865f 100644
--- a/documentation/ref-manual/variables.rst
+++ b/documentation/ref-manual/variables.rst
@@ -12261,6 +12261,13 @@ system and gives an overview of their function and contents.
       Wic creation process.
 
    :term:`WIC_SECTOR_SIZE`
+
+      .. warning::
+
+         This variable is deprecated in favor of the ``--sector-size`` wic
+         command-line argument. See :ref:`ref-migration-6-0-wic-sector-size-change`
+         for more information.
+
       The variable :term:`WIC_SECTOR_SIZE` controls the sector size of Wic
       images. In the background, this controls the value of the
       ``PARTED_SECTOR_SIZE`` environment variable passed to the ``parted``