diff --git a/include/miniocpp/args.h b/include/miniocpp/args.h
index d1c4d12..ed6c485 100644
--- a/include/miniocpp/args.h
+++ b/include/miniocpp/args.h
@@ -360,6 +360,7 @@ struct ComposeObjectArgs : public ObjectWriteArgs {
 
 struct UploadObjectArgs : public PutObjectBaseArgs {
   std::string filename;
+  std::ios_base::openmode openmode = std::ios_base::in;
   http::ProgressFunction progressfunc = nullptr;
   void* progress_userdata = nullptr;
 
diff --git a/src/client.cc b/src/client.cc
index 94ffd56..62e2cb6 100644
--- a/src/client.cc
+++ b/src/client.cc
@@ -777,7 +777,7 @@ UploadObjectResponse Client::UploadObject(UploadObjectArgs args) {
   std::ifstream file;
   file.exceptions(std::ifstream::failbit | std::ifstream::badbit);
   try {
-    file.open(args.filename);
+    file.open(args.filename, args.openmode);
   } catch (std::system_error& err) {
     return error::make<UploadObjectResponse>(
         "unable to open file " + args.filename + "; " + err.code().message());