diff --git a/script/api_protobuf/api_protobuf.py b/script/api_protobuf/api_protobuf.py
index 97cc95e556..7f9067cd22 100644
--- a/script/api_protobuf/api_protobuf.py
+++ b/script/api_protobuf/api_protobuf.py
@@ -821,7 +821,7 @@ cpp += """\
 namespace esphome {
 namespace api {
 
-static const char *TAG = "api.service";
+static const char *const TAG = "api.service";
 
 """