diff --git a/README.rst b/README.rst
index feb4e91ac..8a9c2b594 100644
--- a/README.rst
+++ b/README.rst
@@ -96,6 +96,7 @@ in development
 * Add highlighting when clicking on "View In Hierarchy" link from class page.
 * Recognize variadic generics type variables (PEP 646).
 * Fix support for introspection of cython3 generated modules.
+* Instance variables are marked as such across subclasses.
 
 pydoctor 23.4.1
 ^^^^^^^^^^^^^^^
diff --git a/pydoctor/model.py b/pydoctor/model.py
index 7a720f5e1..2cb8cc375 100644
--- a/pydoctor/model.py
+++ b/pydoctor/model.py
@@ -1452,6 +1452,9 @@ def postProcess(self) -> None:
             if is_exception(cls):
                 cls.kind = DocumentableKind.EXCEPTION
 
+        for attrib in self.objectsOfType(Attribute):
+            _inherits_instance_variable_kind(attrib)
+
         for post_processor in self._post_processors:
             post_processor(self)
 
@@ -1463,6 +1466,20 @@ def fetchIntersphinxInventories(self, cache: CacheT) -> None:
         for url in self.options.intersphinx:
             self.intersphinx.update(cache, url)
 
+def _inherits_instance_variable_kind(attr: Attribute) -> None:
+    """
+    If any of the inherited members of a class variable is an instance variable,
+    then the subclass' class variable become an instance variable as well.
+    """
+    if attr.kind is not DocumentableKind.CLASS_VARIABLE:
+        return
+    docsources = attr.docsources()
+    next(docsources)
+    for inherited in docsources:
+        if inherited.kind is DocumentableKind.INSTANCE_VARIABLE:
+            attr.kind = DocumentableKind.INSTANCE_VARIABLE
+            break
+
 def get_docstring(
         obj: Documentable
         ) -> Tuple[Optional[str], Optional[Documentable]]:
diff --git a/pydoctor/test/test_astbuilder.py b/pydoctor/test/test_astbuilder.py
index 8edba83aa..b5af2de2e 100644
--- a/pydoctor/test/test_astbuilder.py
+++ b/pydoctor/test/test_astbuilder.py
@@ -2421,6 +2421,76 @@ def __init__(self):
     mod = fromText(src, systemcls=systemcls)
     assert getConstructorsText(mod.contents['Animal']) == "Animal()"
 
+@systemcls_param
+def test_class_var_override(systemcls: Type[model.System]) -> None:
+
+    src = '''\
+    from number import Number
+    class Thing(object):
+        def __init__(self):
+            self.var: Number = 1
+    class Stuff(Thing):
+        var:float
+        '''
+
+    mod = fromText(src, systemcls=systemcls, modname='mod')
+    var = mod.system.allobjects['mod.Stuff.var']
+    assert var.kind == model.DocumentableKind.INSTANCE_VARIABLE
+
+@systemcls_param
+def test_class_var_override_traverse_subclasses(systemcls: Type[model.System]) -> None:
+
+    src = '''\
+    from number import Number
+    class Thing(object):
+        def __init__(self):
+            self.var: Number = 1
+    class _Stuff(Thing):
+        ...
+    class Stuff(_Stuff):
+        var:float
+        '''
+
+    mod = fromText(src, systemcls=systemcls, modname='mod')
+    var = mod.system.allobjects['mod.Stuff.var']
+    assert var.kind == model.DocumentableKind.INSTANCE_VARIABLE
+
+    src = '''\
+    from number import Number
+    class Thing(object):
+        def __init__(self):
+            self.var: Optional[Number] = 0
+    class _Stuff(Thing):
+        var = None
+    class Stuff(_Stuff):
+        var: float
+        '''
+
+    mod = fromText(src, systemcls=systemcls, modname='mod')
+    var = mod.system.allobjects['mod._Stuff.var']
+    assert var.kind == model.DocumentableKind.INSTANCE_VARIABLE
+    
+    mod = fromText(src, systemcls=systemcls, modname='mod')
+    var = mod.system.allobjects['mod.Stuff.var']
+    assert var.kind == model.DocumentableKind.INSTANCE_VARIABLE
+
+def test_class_var_override_attrs() -> None:
+
+    systemcls = AttrsSystem
+
+    src = '''\
+    import attr
+    @attr.s
+    class Thing(object):
+        var = attr.ib()
+    class Stuff(Thing):
+        var: float
+        '''
+
+    mod = fromText(src, systemcls=systemcls, modname='mod')
+    var = mod.system.allobjects['mod.Stuff.var']
+    assert var.kind == model.DocumentableKind.INSTANCE_VARIABLE
+
 @systemcls_param
 def test_explicit_annotation_wins_over_inferred_type(systemcls: Type[model.System]) -> None:
     """