diff --git a/qutebrowser/browser/downloads.py b/qutebrowser/browser/downloads.py
index a03faa07f..81768978d 100644
--- a/qutebrowser/browser/downloads.py
+++ b/qutebrowser/browser/downloads.py
@@ -104,6 +104,11 @@ def create_full_filename(basename, filename):
     Return:
         The full absolute path, or None if filename creation was not possible.
     """
+    # Remove chars which can't be encoded in the filename encoding.
+    # See https://github.com/The-Compiler/qutebrowser/issues/427
+    encoding = sys.getfilesystemencoding()
+    filename = utils.force_encoding(filename, encoding)
+    basename = utils.force_encoding(basename, encoding)
     if os.path.isabs(filename) and os.path.isdir(filename):
         # We got an absolute directory from the user, so we save it under
         # the default filename in that directory.
@@ -523,10 +528,6 @@ class DownloadItem(QObject):
                              "existing: {}, fileobj {}".format(
                                  filename, self._filename, self.fileobj))
         filename = os.path.expanduser(filename)
-        # Remove chars which can't be encoded in the filename encoding.
-        # See https://github.com/The-Compiler/qutebrowser/issues/427
-        encoding = sys.getfilesystemencoding()
-        filename = utils.force_encoding(filename, encoding)
         self._filename = create_full_filename(self.basename, filename)
         if self._filename is None:
             # We only got a filename (without directory) or a relative path
diff --git a/tests/integration/test_invocations.py b/tests/integration/test_invocations.py
index c88462207..a13c6ac25 100644
--- a/tests/integration/test_invocations.py
+++ b/tests/integration/test_invocations.py
@@ -17,7 +17,7 @@
 # You should have received a copy of the GNU General Public License
 # along with qutebrowser.  If not, see <http://www.gnu.org/licenses/>.
 
-"""Test starting qutebrowser with various commandline arguments."""
+"""Test starting qutebrowser with special arguments/environments."""
 
 import pytest
 
@@ -51,3 +51,23 @@ def test_no_config(tmpdir, quteproc_new):
     quteproc_new.start(args, env=env)
     quteproc_new.send_cmd(':quit')
     quteproc_new.wait_for_quit()
+
+
+@pytest.mark.linux
+def test_ascii_locale(httpbin, tmpdir, quteproc_new):
+    """Test downloads with LC_ALL=C set.
+
+    https://github.com/The-Compiler/qutebrowser/issues/908
+    """
+    args = ['--debug', '--no-err-windows', '--temp-basedir', 'about:blank']
+    quteproc_new.start(args, env={'LC_ALL': 'C'})
+    quteproc_new.set_setting('storage', 'download-directory', str(tmpdir))
+    quteproc_new.set_setting('storage', 'prompt-download-directory', 'false')
+    url = 'http://localhost:{port}/data/downloads/ä-issue908.bin'.format(
+        port=httpbin.port)
+    quteproc_new.send_cmd(':download {}'.format(url))
+    quteproc_new.send_cmd(':quit')
+    quteproc_new.wait_for_quit()
+
+    assert len(tmpdir.listdir()) == 1
+    assert (tmpdir / '?-issue908.bin').exists()