diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst
index b4c6bc957..5713da32e 100644
--- a/documentation/ref-manual/variables.rst
+++ b/documentation/ref-manual/variables.rst
@@ -12283,6 +12283,14 @@ system and gives an overview of their function and contents.
       Additionally, you should also set the
       :term:`USERADD_ERROR_DYNAMIC` variable.
 
+   :term:`USERMOD_PARAMS`
+      When a recipe inherits the :ref:`ref-classes-useradd` class, this variable
+      specifies for a package what parameters should be passed to the ``usermod``
+      command if you wish to modify a user when the package is installed.
+      Is is typically used to add the user to one or more groups. For example::
+
+         USERMOD_PARAM:${PN} = "--append --groups group1,group2 user"
+
    :term:`VIRTUAL-RUNTIME`
       :term:`VIRTUAL-RUNTIME` is a commonly used prefix for defining virtual
       packages for runtime usage, typically for use in :term:`RDEPENDS`