diff --git a/gio/gdbus-2.0/codegen/codegen.py b/gio/gdbus-2.0/codegen/codegen.py
index aa1280f59..55cd7bb34 100644
--- a/gio/gdbus-2.0/codegen/codegen.py
+++ b/gio/gdbus-2.0/codegen/codegen.py
@@ -112,14 +112,11 @@ class HeaderCodeGenerator:
             if len(i.methods) > 0:
                 self.outfile.write('\n')
                 for m in i.methods:
-                    unix_fd = False
-                    if utils.lookup_annotation(m.annotations, 'org.gtk.GDBus.C.UnixFD'):
-                        unix_fd = True
                     key = (m.since, '_method_%s'%m.name_lower)
                     value  = '  gboolean (*handle_%s) (\n'%(m.name_lower)
                     value += '    %s *object,\n'%(i.camel_name)
                     value += '    GDBusMethodInvocation *invocation'%()
-                    if unix_fd:
+                    if m.unix_fd:
                         value += ',\n    GUnixFDList *fd_list'
                     for a in m.in_args:
                         value += ',\n    %sarg_%s'%(a.ctype_in, a.name)
@@ -176,15 +173,12 @@ class HeaderCodeGenerator:
                 self.outfile.write('\n')
                 self.outfile.write('/* D-Bus method call completion functions: */\n')
                 for m in i.methods:
-                    unix_fd = False
-                    if utils.lookup_annotation(m.annotations, 'org.gtk.GDBus.C.UnixFD'):
-                        unix_fd = True
                     if m.deprecated:
                         self.outfile.write('G_GNUC_DEPRECATED ')
                     self.outfile.write('void %s_complete_%s (\n'
                                        '    %s *object,\n'
                                        '    GDBusMethodInvocation *invocation'%(i.name_lower, m.name_lower, i.camel_name))
-                    if unix_fd:
+                    if m.unix_fd:
                         self.outfile.write(',\n    GUnixFDList *fd_list')
                     for a in m.out_args:
                         self.outfile.write(',\n    %s%s'%(a.ctype_in, a.name))
@@ -212,9 +206,6 @@ class HeaderCodeGenerator:
                 self.outfile.write('\n')
                 self.outfile.write('/* D-Bus method calls: */\n')
                 for m in i.methods:
-                    unix_fd = False
-                    if utils.lookup_annotation(m.annotations, 'org.gtk.GDBus.C.UnixFD'):
-                        unix_fd = True
                     # async begin
                     if m.deprecated:
                         self.outfile.write('G_GNUC_DEPRECATED ')
@@ -222,7 +213,7 @@ class HeaderCodeGenerator:
                                        '    %s *proxy'%(i.name_lower, m.name_lower, i.camel_name))
                     for a in m.in_args:
                         self.outfile.write(',\n    %sarg_%s'%(a.ctype_in, a.name))
-                    if unix_fd:
+                    if m.unix_fd:
                         self.outfile.write(',\n    GUnixFDList *fd_list')
                     self.outfile.write(',\n'
                                        '    GCancellable *cancellable,\n'
@@ -236,7 +227,7 @@ class HeaderCodeGenerator:
                                        '    %s *proxy'%(i.name_lower, m.name_lower, i.camel_name))
                     for a in m.out_args:
                         self.outfile.write(',\n    %sout_%s'%(a.ctype_out, a.name))
-                    if unix_fd:
+                    if m.unix_fd:
                         self.outfile.write(',\n    GUnixFDList **out_fd_list')
                     self.outfile.write(',\n'
                                        '    GAsyncResult *res,\n'
@@ -249,11 +240,11 @@ class HeaderCodeGenerator:
                                        '    %s *proxy'%(i.name_lower, m.name_lower, i.camel_name))
                     for a in m.in_args:
                         self.outfile.write(',\n    %sarg_%s'%(a.ctype_in, a.name))
-                    if unix_fd:
+                    if m.unix_fd:
                         self.outfile.write(',\n    GUnixFDList  *fd_list')
                     for a in m.out_args:
                         self.outfile.write(',\n    %sout_%s'%(a.ctype_out, a.name))
-                    if unix_fd:
+                    if m.unix_fd:
                         self.outfile.write(',\n    GUnixFDList **out_fd_list')
                     self.outfile.write(',\n'
                                        '    GCancellable *cancellable,\n'
@@ -1153,9 +1144,6 @@ class CodeGenerator:
 
             if len(i.methods) > 0:
                 for m in i.methods:
-                    unix_fd = False
-                    if utils.lookup_annotation(m.annotations, 'org.gtk.GDBus.C.UnixFD'):
-                        unix_fd = True
                     self.generate_args('_%s_method_info_%s_IN_ARG'%(i.name_lower, m.name_lower), m.in_args)
                     self.generate_args('_%s_method_info_%s_OUT_ARG'%(i.name_lower, m.name_lower), m.out_args)
 
@@ -1181,7 +1169,7 @@ class CodeGenerator:
                     self.outfile.write('  },\n'
                                        '  "handle-%s",\n'
                                        '  %s\n'
-                                       %(m.name_hyphen, 'TRUE' if unix_fd else 'FALSE'))
+                                       %(m.name_hyphen, 'TRUE' if m.unix_fd else 'FALSE'))
                     self.outfile.write('};\n'
                                        '\n')
 
@@ -1399,16 +1387,13 @@ class CodeGenerator:
         if len(i.methods) > 0:
             self.outfile.write('  /* GObject signals for incoming D-Bus method calls: */\n')
             for m in i.methods:
-                unix_fd = False
-                if utils.lookup_annotation(m.annotations, 'org.gtk.GDBus.C.UnixFD'):
-                    unix_fd = True
                 self.outfile.write(self.docbook_gen.expand(
                         '  /**\n'
                         '   * %s::handle-%s:\n'
                         '   * @object: A #%s.\n'
                         '   * @invocation: A #GDBusMethodInvocation.\n'
                         %(i.camel_name, m.name_hyphen, i.camel_name), False))
-                if unix_fd:
+                if m.unix_fd:
                     self.outfile.write('   * @fd_list: (nullable): A #GUnixFDList or %NULL.\n')
                 for a in m.in_args:
                     self.outfile.write('   * @arg_%s: Argument passed by remote caller.\n'%(a.name))
@@ -1421,7 +1406,7 @@ class CodeGenerator:
                         '   * Returns: %%TRUE if the invocation was handled, %%FALSE to let other signal handlers run.\n'
                         %(i.name, m.name, i.name_lower, m.name_lower), False))
                 self.write_gtkdoc_deprecated_and_since_and_close(m, self.outfile, 2)
-                if unix_fd:
+                if m.unix_fd:
                     extra_args = 2
                 else:
                     extra_args = 1
@@ -1436,7 +1421,7 @@ class CodeGenerator:
                                    '    %d,\n'
                                    '    G_TYPE_DBUS_METHOD_INVOCATION'
                                    %(m.name_hyphen, i.camel_name, m.name_lower, len(m.in_args) + extra_args))
-                if unix_fd:
+                if m.unix_fd:
                     self.outfile.write(', G_TYPE_UNIX_FD_LIST')
                 for a in m.in_args:
                     self.outfile.write(', %s'%(a.gtype))
@@ -1662,9 +1647,6 @@ class CodeGenerator:
 
     def generate_method_calls(self, i):
         for m in i.methods:
-            unix_fd = False
-            if utils.lookup_annotation(m.annotations, 'org.gtk.GDBus.C.UnixFD'):
-                unix_fd = True
             # async begin
             self.outfile.write('/**\n'
                                ' * %s_call_%s:\n'
@@ -1672,7 +1654,7 @@ class CodeGenerator:
                                %(i.name_lower, m.name_lower, i.camel_name))
             for a in m.in_args:
                 self.outfile.write(' * @arg_%s: Argument to pass with the method invocation.\n'%(a.name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(' * @fd_list: (nullable): A #GUnixFDList or %NULL.\n')
             self.outfile.write(self.docbook_gen.expand(
                     ' * @cancellable: (nullable): A #GCancellable or %%NULL.\n'
@@ -1691,14 +1673,14 @@ class CodeGenerator:
                                '    %s *proxy'%(i.name_lower, m.name_lower, i.camel_name))
             for a in m.in_args:
                 self.outfile.write(',\n    %sarg_%s'%(a.ctype_in, a.name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(',\n    GUnixFDList *fd_list')
             self.outfile.write(',\n'
                                '    GCancellable *cancellable,\n'
                                '    GAsyncReadyCallback callback,\n'
                                '    gpointer user_data)\n'
                                '{\n')
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write('  g_dbus_proxy_call_with_unix_fd_list (G_DBUS_PROXY (proxy),\n')
             else:
                 self.outfile.write('  g_dbus_proxy_call (G_DBUS_PROXY (proxy),\n')
@@ -1712,7 +1694,7 @@ class CodeGenerator:
             self.outfile.write('),\n'
                                '    G_DBUS_CALL_FLAGS_NONE,\n'
                                '    -1,\n')
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write('    fd_list,\n')
             self.outfile.write('    cancellable,\n'
                                '    callback,\n'
@@ -1726,7 +1708,7 @@ class CodeGenerator:
                                %(i.name_lower, m.name_lower, i.camel_name))
             for a in m.out_args:
                 self.outfile.write(' * @out_%s: (out) (optional)%s: Return location for return parameter or %%NULL to ignore.\n'%(a.name, ' ' + a.array_annotation if a.array_annotation else ''))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(' * @out_fd_list: (out) (optional): Return location for a #GUnixFDList or %NULL to ignore.\n')
             self.outfile.write(self.docbook_gen.expand(
                     ' * @res: The #GAsyncResult obtained from the #GAsyncReadyCallback passed to %s_call_%s().\n'
@@ -1742,14 +1724,14 @@ class CodeGenerator:
                                '    %s *proxy'%(i.name_lower, m.name_lower, i.camel_name))
             for a in m.out_args:
                 self.outfile.write(',\n    %sout_%s'%(a.ctype_out, a.name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(',\n    GUnixFDList **out_fd_list')
             self.outfile.write(',\n'
                                '    GAsyncResult *res,\n'
                                '    GError **error)\n'
                                '{\n'
                                '  GVariant *_ret;\n')
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write('  _ret = g_dbus_proxy_call_with_unix_fd_list_finish (G_DBUS_PROXY (proxy), out_fd_list, res, error);\n')
             else:
                 self.outfile.write('  _ret = g_dbus_proxy_call_finish (G_DBUS_PROXY (proxy), res, error);\n')
@@ -1777,11 +1759,11 @@ class CodeGenerator:
                                %(i.name_lower, m.name_lower, i.camel_name))
             for a in m.in_args:
                 self.outfile.write(' * @arg_%s: Argument to pass with the method invocation.\n'%(a.name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(' * @fd_list: (nullable): A #GUnixFDList or %NULL.\n')
             for a in m.out_args:
                 self.outfile.write(' * @out_%s: (out) (optional)%s: Return location for return parameter or %%NULL to ignore.\n'%(a.name, ' ' + a.array_annotation if a.array_annotation else ''))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(' * @out_fd_list: (out): Return location for a #GUnixFDList or %NULL.\n')
             self.outfile.write(self.docbook_gen.expand(
                     ' * @cancellable: (nullable): A #GCancellable or %%NULL.\n'
@@ -1799,18 +1781,18 @@ class CodeGenerator:
                                '    %s *proxy'%(i.name_lower, m.name_lower, i.camel_name))
             for a in m.in_args:
                 self.outfile.write(',\n    %sarg_%s'%(a.ctype_in, a.name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(',\n    GUnixFDList  *fd_list')
             for a in m.out_args:
                 self.outfile.write(',\n    %sout_%s'%(a.ctype_out, a.name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(',\n    GUnixFDList **out_fd_list')
             self.outfile.write(',\n'
                                '    GCancellable *cancellable,\n'
                                '    GError **error)\n'
                                '{\n'
                                '  GVariant *_ret;\n')
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write('  _ret = g_dbus_proxy_call_with_unix_fd_list_sync (G_DBUS_PROXY (proxy),\n')
             else:
                 self.outfile.write('  _ret = g_dbus_proxy_call_sync (G_DBUS_PROXY (proxy),\n')
@@ -1824,7 +1806,7 @@ class CodeGenerator:
             self.outfile.write('),\n'
                                '    G_DBUS_CALL_FLAGS_NONE,\n'
                                '    -1,\n')
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write('    fd_list,\n'
                                    '    out_fd_list,\n')
             self.outfile.write('    cancellable,\n'
@@ -1849,15 +1831,12 @@ class CodeGenerator:
 
     def generate_method_completers(self, i):
         for m in i.methods:
-            unix_fd = False
-            if utils.lookup_annotation(m.annotations, 'org.gtk.GDBus.C.UnixFD'):
-                unix_fd = True
             self.outfile.write('/**\n'
                                ' * %s_complete_%s:\n'
                                ' * @object: A #%s.\n'
                                ' * @invocation: (transfer full): A #GDBusMethodInvocation.\n'
                                %(i.name_lower, m.name_lower, i.camel_name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(' * @fd_list: (nullable): A #GUnixFDList or %NULL.\n')
             for a in m.out_args:
                 self.outfile.write(' * @%s: Parameter to return.\n'%(a.name))
@@ -1872,14 +1851,14 @@ class CodeGenerator:
                                '%s_complete_%s (\n'
                                '    %s *object,\n'
                                '    GDBusMethodInvocation *invocation'%(i.name_lower, m.name_lower, i.camel_name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write(',\n    GUnixFDList *fd_list')
             for a in m.out_args:
                 self.outfile.write(',\n    %s%s'%(a.ctype_in, a.name))
             self.outfile.write(')\n'
                                '{\n')
 
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write('  g_dbus_method_invocation_return_value_with_unix_fd_list (invocation,\n'
                                    '    g_variant_new ("(')
             else:
@@ -1890,7 +1869,7 @@ class CodeGenerator:
             self.outfile.write(')"')
             for a in m.out_args:
                 self.outfile.write(',\n                   %s'%(a.name))
-            if unix_fd:
+            if m.unix_fd:
                 self.outfile.write('),\n    fd_list);\n')
             else:
                 self.outfile.write('));\n')
diff --git a/gio/gdbus-2.0/codegen/dbustypes.py b/gio/gdbus-2.0/codegen/dbustypes.py
index 60c53c4be..498ea668b 100644
--- a/gio/gdbus-2.0/codegen/dbustypes.py
+++ b/gio/gdbus-2.0/codegen/dbustypes.py
@@ -260,6 +260,7 @@ class Method:
         self.doc_string = ''
         self.since = ''
         self.deprecated = False
+        self.unix_fd = False
 
     def post_process(self, interface_prefix, cns, cns_upper, cns_lower, containing_iface):
         if len(self.doc_string) == 0:
@@ -283,14 +284,21 @@ class Method:
         for a in self.in_args:
             a.post_process(interface_prefix, cns, cns_upper, cns_lower, arg_count)
             arg_count += 1
+            if 'h' in a.signature:
+                self.unix_fd = True
 
         for a in self.out_args:
             a.post_process(interface_prefix, cns, cns_upper, cns_lower, arg_count)
             arg_count += 1
+            if 'h' in a.signature:
+                self.unix_fd = True
 
         if utils.lookup_annotation(self.annotations, 'org.freedesktop.DBus.Deprecated') == 'true':
             self.deprecated = True
 
+        if utils.lookup_annotation(self.annotations, 'org.gtk.GDBus.C.UnixFD'):
+            self.unix_fd = True
+
         for a in self.annotations:
             a.post_process(interface_prefix, cns, cns_upper, cns_lower, self)
 
diff --git a/gio/tests/gdbus-test-codegen.c b/gio/tests/gdbus-test-codegen.c
index 985cb1095..ba0f6ed61 100644
--- a/gio/tests/gdbus-test-codegen.c
+++ b/gio/tests/gdbus-test-codegen.c
@@ -2588,6 +2588,61 @@ test_standalone_interface_info (void)
   g_clear_object (&skel);
 }
 
+/* ---------------------------------------------------------------------------------------------------- */
+static gboolean
+handle_hello_fd (FooiGenFDPassing *object,
+                 GDBusMethodInvocation *invocation,
+                 GUnixFDList *fd_list,
+                 const gchar *arg_greeting)
+{
+  foo_igen_fdpassing_complete_hello_fd (object, invocation, fd_list, arg_greeting);
+  return TRUE;
+}
+
+static gboolean
+handle_no_annotation (FooiGenFDPassing *object,
+                      GDBusMethodInvocation *invocation,
+                      GUnixFDList *fd_list,
+                      GVariant *arg_greeting,
+                      const gchar *arg_greeting_locale)
+{
+  foo_igen_fdpassing_complete_no_annotation (object, invocation, fd_list, arg_greeting, arg_greeting_locale);
+  return TRUE;
+}
+
+static gboolean
+handle_no_annotation_nested (FooiGenFDPassing *object,
+                             GDBusMethodInvocation *invocation,
+                             GUnixFDList *fd_list,
+                             GVariant *arg_files)
+{
+  foo_igen_fdpassing_complete_no_annotation_nested (object, invocation, fd_list);
+  return TRUE;
+}
+
+/* Test that generated code for methods includes GUnixFDList arguments if:
+ * - the method is explicitly annotated as C.UnixFD; or
+ * - the method signature contains the type 'h'
+ */
+static void
+test_unix_fd_list (void)
+{
+  FooiGenFDPassingIface iface;
+
+  g_test_bug ("https://gitlab.gnome.org/GNOME/glib/issues/1726");
+
+  /* This method is explicitly annotated. */
+  iface.handle_hello_fd = handle_hello_fd;
+  /* This one is not, but it's got an in and out 'h' parameter so should
+   * automatically grow GUnixFDList arguments.
+   */
+  iface.handle_no_annotation = handle_no_annotation;
+  /* This method has an 'h' inside a complex type. */
+  iface.handle_no_annotation_nested = handle_no_annotation_nested;
+
+  (void) iface;
+}
+
 /* ---------------------------------------------------------------------------------------------------- */
 
 int
@@ -2603,6 +2658,7 @@ main (int   argc,
   g_test_add_func ("/gdbus/codegen/autocleanups", test_autocleanups);
   g_test_add_func ("/gdbus/codegen/deprecations", test_deprecations);
   g_test_add_func ("/gdbus/codegen/standalone-interface-info", test_standalone_interface_info);
+  g_test_add_func ("/gdbus/codegen/unix-fd-list", test_unix_fd_list);
 
   return session_bus_run ();
 }
diff --git a/gio/tests/test-codegen.xml b/gio/tests/test-codegen.xml
index 39d8769c7..3090cad4a 100644
--- a/gio/tests/test-codegen.xml
+++ b/gio/tests/test-codegen.xml
@@ -481,6 +481,15 @@
       <arg name="greeting" direction="in" type="s"/>
       <arg name="response" direction="out" type="s"/>
     </method>
+    <method name="NoAnnotation">
+      <arg name="greeting" direction="in" type="h"/>
+      <arg name="greeting_locale" direction="in" type="s"/>
+      <arg name="response" direction="out" type="h"/>
+      <arg name="response_locale" direction="out" type="s"/>
+    </method>
+    <method name="NoAnnotationNested">
+      <arg name="files" type="a{sh}" direction="in"/>
+    </method>
   </interface>
 
   <interface name="Naming">