diff --git a/ckan/lib/formatters.py b/ckan/lib/formatters.py
index f731144c606..ccf9f437439 100644
--- a/ckan/lib/formatters.py
+++ b/ckan/lib/formatters.py
@@ -99,12 +99,10 @@ def months_between(date1, date2):
         return months
 
     if not show_date:
-        now = datetime.datetime.utcnow()
-        if datetime_.tzinfo is not None:
-            now = now.replace(tzinfo=datetime_.tzinfo)
-        else:
-            now = now.replace(tzinfo=pytz.utc)
-            datetime_ = datetime_.replace(tzinfo=pytz.utc)
+        now = datetime.datetime.now(pytz.utc)
+        if datetime_.tzinfo is None:
+            datetime_ = datetime_.astimezone(pytz.utc)
+
         date_diff = now - datetime_
         days = date_diff.days
         if days < 1 and now > datetime_:
diff --git a/ckan/model/activity.py b/ckan/model/activity.py
index cfd6d02e2a5..fdfa52660cc 100644
--- a/ckan/model/activity.py
+++ b/ckan/model/activity.py
@@ -40,7 +40,7 @@ class Activity(domain_object.DomainObject):
     def __init__(self, user_id, object_id, revision_id, activity_type,
             data=None):
         self.id = _types.make_uuid()
-        self.timestamp = datetime.datetime.now()
+        self.timestamp = datetime.datetime.utcnow()
         self.user_id = user_id
         self.object_id = object_id
         self.revision_id = revision_id