diff --git a/mypy/checker.py b/mypy/checker.py
index 851f23185f4f..b8898f1ebf32 100644
--- a/mypy/checker.py
+++ b/mypy/checker.py
@@ -2376,7 +2376,20 @@ def check_assignment(self, lvalue: Lvalue, rvalue: Expression, infer_lvalue_type
                 self.check_indexed_assignment(index_lvalue, rvalue, lvalue)
 
             if inferred:
-                rvalue_type = self.expr_checker.accept(rvalue)
+                type_hint = None
+                if isinstance(lvalue, RefExpr):
+                    inferred_node = lvalue.node
+                    if (isinstance(inferred_node, Var) and
+                            lvalue.kind in (MDEF, None) and  # None for Vars defined via self
+                            len(inferred_node.info.bases) > 0):
+                        for base in inferred_node.info.mro[1:]:
+                            base_type, base_node = self.lvalue_type_from_base(inferred_node, base)
+
+                            if base_type:
+                                type_hint = base_type
+                                break
+
+                rvalue_type = self.expr_checker.accept(rvalue, type_hint)
                 if not inferred.is_final:
                     rvalue_type = remove_instance_last_known_values(rvalue_type)
                 self.infer_variable_type(inferred, lvalue, rvalue_type, rvalue)
diff --git a/test-data/unit/check-inference.test b/test-data/unit/check-inference.test
index 4de6e4a76f92..f2f5424a98bf 100644
--- a/test-data/unit/check-inference.test
+++ b/test-data/unit/check-inference.test
@@ -2813,8 +2813,8 @@ class C(A):
     x = ['12']
 
 reveal_type(A.x) # N: Revealed type is "builtins.list[Any]"
-reveal_type(B.x) # N: Revealed type is "builtins.list[builtins.int]"
-reveal_type(C.x) # N: Revealed type is "builtins.list[builtins.str]"
+reveal_type(B.x) # N: Revealed type is "builtins.list[Any]"
+reveal_type(C.x) # N: Revealed type is "builtins.list[Any]"
 
 [builtins fixtures/list.pyi]
 
@@ -3255,3 +3255,20 @@ reveal_type(x)  # N: Revealed type is "builtins.bytes*"
 if x:
     reveal_type(x)  # N: Revealed type is "builtins.bytes*"
 [builtins fixtures/dict.pyi]
+
+[case testInferHintFromBase]
+from typing import Union, List
+
+class A: pass
+class B: pass
+
+U = Union[A, B]
+
+class Base:
+    variable1 : List[U] = []
+    variable2 : List[U] = []
+
+class Derived(Base):
+    variable1 = [A()]
+    variable2 = variable1
+[out]