diff --git a/src/allmydata/test/test_eliotutil.py b/src/allmydata/test/test_eliotutil.py
index 1a8c2f801..0073a7675 100644
--- a/src/allmydata/test/test_eliotutil.py
+++ b/src/allmydata/test/test_eliotutil.py
@@ -57,11 +57,14 @@ from ..util.eliotutil import (
     _parse_destination_description,
     _EliotLogging,
 )
+from ..util.jsonbytes import BytesJSONEncoder
+
 from .common import (
     SyncTestCase,
     AsyncTestCase,
 )
 
+
 class EliotLoggedTestTests(AsyncTestCase):
     def test_returns_none(self):
         Message.log(hello="world")
@@ -94,7 +97,7 @@ class ParseDestinationDescriptionTests(SyncTestCase):
         reactor = object()
         self.assertThat(
             _parse_destination_description("file:-")(reactor),
-            Equals(FileDestination(stdout)),
+            Equals(FileDestination(stdout, encoder=BytesJSONEncoder)),
         )
 
 
diff --git a/src/allmydata/util/eliotutil.py b/src/allmydata/util/eliotutil.py
index 096356dfa..9e3cdd3e1 100644
--- a/src/allmydata/util/eliotutil.py
+++ b/src/allmydata/util/eliotutil.py
@@ -86,6 +86,9 @@ from twisted.internet.defer import (
 )
 from twisted.application.service import Service
 
+from .jsonbytes import BytesJSONEncoder
+
+
 def validateInstanceOf(t):
     """
     Return an Eliot validator that requires values to be instances of ``t``.
@@ -302,7 +305,7 @@ class _DestinationParser(object):
                     rotateLength=rotate_length,
                     maxRotatedFiles=max_rotated_files,
                 )
-        return lambda reactor: FileDestination(get_file())
+        return lambda reactor: FileDestination(get_file(), BytesJSONEncoder)
 
 
 _parse_destination_description = _DestinationParser().parse