diff --git a/CHANGELOG.md b/CHANGELOG.md
index 469726701..673cfea18 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -57,6 +57,9 @@ Increment the:
   request body on a 32-bit build
   [#4630](https://github.com/open-telemetry/opentelemetry-cpp/pull/4630)
 
+* [BUG] Fix a data race on the curl operation's last result code
+  [#4618](https://github.com/open-telemetry/opentelemetry-cpp/pull/4618)
+
 ## [1.29.0] 2026-09-13
 
 * [RELEASE] Bump main branch to 1.29.0-dev (#4259)
diff --git a/ext/src/http/client/curl/http_operation_curl.cc b/ext/src/http/client/curl/http_operation_curl.cc
index a92299597..483e8fbc0 100644
--- a/ext/src/http/client/curl/http_operation_curl.cc
+++ b/ext/src/http/client/curl/http_operation_curl.cc
@@ -508,8 +508,8 @@ HttpOperation::~HttpOperation()
       {
         if (HttpOperationAccessor::GetThreadId(*async_data_) != std::this_thread::get_id())
         {
-          async_data_->result_future.wait();
-          last_curl_result_ = async_data_->result_future.get();
+          // PerformCurlMessage() stores this, then calls the Cleanup() that sets the promise.
+          static_cast<void>(async_data_->result_future.get());
         }
       }
       break;
@@ -533,8 +533,8 @@ void HttpOperation::Finish()
     // We should not wait in callback from Cleanup()
     if (HttpOperationAccessor::GetThreadId(*async_data_) != std::this_thread::get_id())
     {
-      async_data_->result_future.wait();
-      last_curl_result_ = async_data_->result_future.get();
+      // PerformCurlMessage() stores this, then calls the Cleanup() that sets the promise.
+      static_cast<void>(async_data_->result_future.get());
     }
   }
 }