diff --git a/weboob/tools/application/formatters/json.py b/weboob/tools/application/formatters/json.py
index e9ae2350..cfb0f4bf 100644
--- a/weboob/tools/application/formatters/json.py
+++ b/weboob/tools/application/formatters/json.py
@@ -19,6 +19,7 @@
 
 
 from weboob.tools.json import json
+from weboob.capabilities.base import NotAvailable, NotLoaded
 
 from .iformatter import IFormatter
 
@@ -32,12 +33,14 @@ class Encoder(json.JSONEncoder):
         try:
             return json.JSONEncoder.default(self, obj)
         except TypeError:
+            if obj is NotAvailable or obj is NotLoaded:
+                return None
+
             try:
                 dct = obj.to_dict()
             except AttributeError:
                 return str(obj)
-            for z in dct.itervalues():
-                return z
+            return dct
 
 
 class JsonFormatter(IFormatter):