diff --git a/analytics/lib/counts.py b/analytics/lib/counts.py
index 26b0a0bb87..72a8f88a19 100644
--- a/analytics/lib/counts.py
+++ b/analytics/lib/counts.py
@@ -8,7 +8,7 @@ from analytics.models import InstallationCount, RealmCount, \
 from zerver.models import Realm, UserProfile, Message, Stream, \
     UserActivityInterval, RealmAuditLog, models
 from zerver.lib.timestamp import floor_to_day, floor_to_hour, ceiling_to_day, \
-    ceiling_to_hour
+    ceiling_to_hour, verify_UTC
 
 from typing import Any, Callable, Dict, List, Optional, Text, Tuple, Type, Union
 
@@ -78,8 +78,7 @@ def process_count_stat(stat, fill_to_time):
     else:
         raise AssertionError("Unknown frequency: %s" % (stat.frequency,))
 
-    if fill_to_time.tzinfo is None:
-        raise ValueError("fill_to_time must be timezone aware: %s" % (fill_to_time,))
+    verify_UTC(fill_to_time)
     if floor_to_hour(fill_to_time) != fill_to_time:
         raise ValueError("fill_to_time must be on an hour boundary: %s" % (fill_to_time,))
 
diff --git a/analytics/tests/test_counts.py b/analytics/tests/test_counts.py
index 84cc7d8edb..197e938b18 100644
--- a/analytics/tests/test_counts.py
+++ b/analytics/tests/test_counts.py
@@ -15,7 +15,7 @@ from analytics.models import BaseCount, InstallationCount, RealmCount, \
     last_successful_fill
 from zerver.lib.actions import do_create_user, do_deactivate_user, \
     do_activate_user, do_reactivate_user, update_user_activity_interval
-from zerver.lib.timestamp import floor_to_day
+from zerver.lib.timestamp import floor_to_day, TimezoneNotUTCException
 from zerver.models import Realm, UserProfile, Message, Stream, Recipient, \
     Huddle, Client, UserActivityInterval, RealmAuditLog, get_client, get_user
 
@@ -198,8 +198,8 @@ class TestProcessCountStat(AnalyticsTestCase):
         stat = self.make_dummy_count_stat('test stat')
         with self.assertRaises(ValueError):
             process_count_stat(stat, installation_epoch() + 65*self.MINUTE)
-        with self.assertRaises(ValueError):
-            process_count_stat(stat, installation_epoch().replace(tzinfo=None) + self.HOUR)
+        with self.assertRaises(TimezoneNotUTCException):
+            process_count_stat(stat, installation_epoch().replace(tzinfo=None))
 
     # This tests the LoggingCountStat branch of the code in do_delete_counts_at_hour.
     # It is important that do_delete_counts_at_hour not delete any of the collected