diff --git a/ets2panda/checker/ETSAnalyzer.cpp b/ets2panda/checker/ETSAnalyzer.cpp
index ab87ed9b46aab0375ecb4a7396fca515aedbbab6..6617b370466d0645a91458ef6370d6f235454d13 100644
--- a/ets2panda/checker/ETSAnalyzer.cpp
+++ b/ets2panda/checker/ETSAnalyzer.cpp
@@ -2995,7 +2995,7 @@ checker::Type *ETSAnalyzer::Check(ir::UpdateExpression *expr) const
         return expr->SetTsType(checker->GlobalTypeError());
     }
 
-    return expr->SetTsType(operandType);
+    return expr->SetTsType(checker->ApplyUnaryOperatorPromotion(expr->argument_, operandType));
 }
 
 // compile methods for LITERAL EXPRESSIONS in alphabetical order
diff --git a/ets2panda/test/ast/compiler/ets/update_expression_type_widen.ets b/ets2panda/test/ast/compiler/ets/update_expression_type_widen.ets
new file mode 100644
index 0000000000000000000000000000000000000000..43a461178b943b956fa8c11f6be63275f1a613a3
--- /dev/null
+++ b/ets2panda/test/ast/compiler/ets/update_expression_type_widen.ets
@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2025 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+function want_byte(x: byte) {
+}
+let b: byte = 1
+want_byte(++b)
+
+/* @@? 19:1 Error TypeError: No matching call signature for want_byte(Int) */
+/* @@? 19:11 Error TypeError: Type 'Int' is not compatible with type 'Byte' at index 1 */