diff --git a/include/spdlog/details/os-inl.h b/include/spdlog/details/os-inl.h
index 8762d847..16f3d2e9 100644
--- a/include/spdlog/details/os-inl.h
+++ b/include/spdlog/details/os-inl.h
@@ -407,7 +407,7 @@ SPDLOG_INLINE int pid() SPDLOG_NOEXCEPT
 #ifdef _WIN32
     return static_cast<int>(::GetCurrentProcessId());
 #else
-    return ::getpid();
+    return static_cast<int>(::getpid());
 #endif
 }