diff --git a/include/spdlog/common.h b/include/spdlog/common.h
index ef54a798..b420ef82 100644
--- a/include/spdlog/common.h
+++ b/include/spdlog/common.h
@@ -63,7 +63,7 @@ using log_clock = std::chrono::system_clock;
 using sink_ptr = std::shared_ptr < sinks::sink > ;
 using sinks_init_list = std::initializer_list < sink_ptr > ;
 using formatter_ptr = std::shared_ptr<spdlog::formatter>;
-using log_thread_id = std::size_t;
+
 
 //Log level enum
 namespace level
diff --git a/include/spdlog/details/async_log_helper.h b/include/spdlog/details/async_log_helper.h
index ee4c6a01..657c70bb 100644
--- a/include/spdlog/details/async_log_helper.h
+++ b/include/spdlog/details/async_log_helper.h
@@ -59,7 +59,7 @@ class async_log_helper
         std::string logger_name;
         level::level_enum level;
         log_clock::time_point time;
-        log_thread_id thread_id;
+        size_t thread_id;
         std::string txt;
 
         async_msg() = default;
diff --git a/include/spdlog/details/log_msg.h b/include/spdlog/details/log_msg.h
index fd89bd1e..bf58aca9 100644
--- a/include/spdlog/details/log_msg.h
+++ b/include/spdlog/details/log_msg.h
@@ -90,7 +90,7 @@ struct log_msg
     std::string logger_name;
     level::level_enum level;
     log_clock::time_point time;
-    log_thread_id thread_id;
+    size_t thread_id;
     fmt::MemoryWriter raw;
     fmt::MemoryWriter formatted;
 };