diff --git a/CHANGELOG.md b/CHANGELOG.md
index 12888672..d822023a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,4 @@
+* Add tests for file open in append mode.
 * Fix file open with append/append_existing flag on Windows.
 
 --------------------------------------------------------------------------------
diff --git a/test/beast/core/file_test.hpp b/test/beast/core/file_test.hpp
index 280bf727..fac2f45b 100644
--- a/test/beast/core/file_test.hpp
+++ b/test/beast/core/file_test.hpp
@@ -17,7 +17,9 @@
 #include <boost/filesystem/operations.hpp>
 #include <boost/filesystem/fstream.hpp>
 #include <cstdio>
+#include <fstream>
 #include <string>
+#include <iterator>
 #include <type_traits>
 
 namespace boost {
@@ -100,6 +102,20 @@ test_file()
             BEAST_EXPECT(! fs::exists(path));
         };
 
+    auto const consume_file =
+        [](fs::path const& path)
+        {
+            // no exceptions - failure will result in an empty string
+            std::ifstream in;
+            in.open(path.native());
+            noskipws(in);
+            auto s = std::string(
+                std::istream_iterator<char>(in),
+                std::istream_iterator<char>());
+            in.close();
+            return s;
+        };
+
     temp_path path;
 
     // bad file descriptor
@@ -230,7 +246,14 @@ test_file()
             f.open(path, file_mode::append, ec);
             BEAST_EXPECT(! ec);
             BEAST_EXPECT(fs::exists(path));
+            static const std::string extra = "the";
+            f.write(extra.c_str(), extra.size(), ec);
+            BEAST_EXPECT(!ec);
+            f.close(ec);
+            auto s = consume_file(path);
+            BEAST_EXPECT(s == "the");
         }
+
         {
             File f;
             error_code ec;
@@ -238,6 +261,12 @@ test_file()
             f.open(path, file_mode::append, ec);
             BEAST_EXPECT(! ec);
             BEAST_EXPECT(fs::exists(path));
+            static const std::string extra = " cat";
+            f.write(extra.c_str(), extra.size(), ec);
+            BEAST_EXPECT(!ec);
+            f.close(ec);
+            auto s = consume_file(path);
+            BEAST_EXPECTS(s == "the cat", s);
         }
         remove(path);
     }