diff --git a/include/fmt/os.h b/include/fmt/os.h
index f6c0f329858c..43ffd3cf0ac8 100644
--- a/include/fmt/os.h
+++ b/include/fmt/os.h
@@ -401,12 +401,6 @@ class FMT_API ostream final : private detail::buffer<char> {
  private:
   file file_;
 
-  void flush() {
-    if (size() == 0) return;
-    file_.write(data(), size());
-    clear();
-  }
-
   void grow(size_t) override;
 
   ostream(cstring_view path, const detail::ostream_params& params)
@@ -426,6 +420,12 @@ class FMT_API ostream final : private detail::buffer<char> {
     delete[] data();
   }
 
+  void flush() {
+    if (size() == 0) return;
+    file_.write(data(), size());
+    clear();
+  }
+
   template <typename... T>
   friend ostream output_file(cstring_view path, T... params);
 
diff --git a/test/os-test.cc b/test/os-test.cc
index b2bd20f2a2c9..01ab7036c678 100644
--- a/test/os-test.cc
+++ b/test/os-test.cc
@@ -336,6 +336,14 @@ TEST(ostream_test, truncate) {
   EXPECT_EQ("foo", read(in, 4));
 }
 
+TEST(ostream_test, flush) {
+  auto out = fmt::output_file("test-file");
+  out.print("x");
+  out.flush();
+  auto in = fmt::file("test-file", file::RDONLY);
+  EXPECT_READ(in, "x");
+}
+
 TEST(file_test, default_ctor) {
   file f;
   EXPECT_EQ(-1, f.descriptor());