diff --git a/crates/ty_python_semantic/src/types.rs b/crates/ty_python_semantic/src/types.rs
index d66e85dc25..c8d1c00280 100644
--- a/crates/ty_python_semantic/src/types.rs
+++ b/crates/ty_python_semantic/src/types.rs
@@ -7267,10 +7267,7 @@ impl<'db> Type<'db> {
             }
 
             (Some(Place::Defined(new_method, ..)), Place::Defined(init_method, ..)) => {
-                let callable = UnionBuilder::new(db)
-                    .add(*new_method)
-                    .add(*init_method)
-                    .build();
+                let callable = UnionType::from_elements(db, [new_method, init_method]);
 
                 let new_method_bindings = new_method
                     .bindings(db)
@@ -10758,11 +10755,7 @@ fn walk_type_var_constraints<'db, V: visitor::TypeVisitor<'db> + ?Sized>(
 
 impl<'db> TypeVarConstraints<'db> {
     fn as_type(self, db: &'db dyn Db) -> Type<'db> {
-        let mut builder = UnionBuilder::new(db);
-        for ty in self.elements(db) {
-            builder = builder.add(*ty);
-        }
-        builder.build()
+        UnionType::from_elements(db, self.elements(db))
     }
 
     fn to_instance(self, db: &'db dyn Db) -> Option<TypeVarConstraints<'db>> {
diff --git a/crates/ty_python_semantic/src/types/infer/builder/type_expression.rs b/crates/ty_python_semantic/src/types/infer/builder/type_expression.rs
index f5cf054bd8..933b2cbe56 100644
--- a/crates/ty_python_semantic/src/types/infer/builder/type_expression.rs
+++ b/crates/ty_python_semantic/src/types/infer/builder/type_expression.rs
@@ -1083,13 +1083,9 @@ impl<'db> TypeInferenceBuilder<'db, '_> {
                     &mut self.inner_expression_inference_state,
                     InnerExpressionInferenceState::Get,
                 );
-                let union = union
-                    .elements(self.db())
-                    .iter()
-                    .fold(UnionBuilder::new(self.db()), |builder, elem| {
-                        builder.add(self.infer_subscript_type_expression(subscript, *elem))
-                    })
-                    .build();
+                let union = union.map(self.db(), |element| {
+                    self.infer_subscript_type_expression(subscript, *element)
+                });
                 self.inner_expression_inference_state = previous_slice_inference_state;
                 union
             }
diff --git a/crates/ty_python_semantic/src/types/narrow.rs b/crates/ty_python_semantic/src/types/narrow.rs
index 88958752c2..101bc159a7 100644
--- a/crates/ty_python_semantic/src/types/narrow.rs
+++ b/crates/ty_python_semantic/src/types/narrow.rs
@@ -926,10 +926,7 @@ impl<'db, 'ast> NarrowingConstraintsBuilder<'db, 'ast> {
                 .build();
 
             // Keep order: first literal complement, then broader arms.
-            let result = UnionBuilder::new(self.db)
-                .add(narrowed_single)
-                .add(rest_union)
-                .build();
+            let result = UnionType::from_elements(self.db, [narrowed_single, rest_union]);
             Some(result)
         } else {
             None