diff --git a/app/serialization.py b/app/serialization.py
index 3a6699f6b..dfe2f4bb6 100644
--- a/app/serialization.py
+++ b/app/serialization.py
@@ -163,7 +163,9 @@ def serialize_host(
     if "reporter" in fields:
         serialized_host["reporter"] = host.reporter
     if "per_reporter_staleness" in fields:
-        serialized_host["per_reporter_staleness"] = host.per_reporter_staleness
+        serialized_host["per_reporter_staleness"] = _serialize_per_reporter_staleness(
+            host, staleness, staleness_timestamps
+        )
     if "stale_timestamp" in fields:
         serialized_host["stale_timestamp"] = stale_timestamp and _serialize_staleness_to_string(stale_timestamp)
     if "stale_warning_timestamp" in fields:
@@ -407,3 +409,21 @@ def serialize_staleness_to_dict(staleness_obj) -> dict:
         "immutable_time_to_stale_warning": staleness_obj.immutable_time_to_stale_warning,
         "immutable_time_to_delete": staleness_obj.immutable_time_to_delete,
     }
+
+
+def _serialize_per_reporter_staleness(host, staleness, staleness_timestamps):
+    for reporter in host.per_reporter_staleness:
+        if host.system_profile_facts.get("host_type") == "edge":
+            stale_timestamp = staleness_timestamps.stale_timestamp(
+                _deserialize_datetime(host.per_reporter_staleness[reporter]["last_check_in"]),
+                staleness["immutable_time_to_stale"],
+            )
+        else:
+            stale_timestamp = staleness_timestamps.stale_timestamp(
+                _deserialize_datetime(host.per_reporter_staleness[reporter]["last_check_in"]),
+                staleness["conventional_time_to_stale"],
+            )
+
+        host.per_reporter_staleness[reporter]["stale_timestamp"] = _serialize_staleness_to_string(stale_timestamp)
+
+        return host.per_reporter_staleness
diff --git a/tests/fixtures/mq_fixtures.py b/tests/fixtures/mq_fixtures.py
index fd2f230e4..88459fe4e 100644
--- a/tests/fixtures/mq_fixtures.py
+++ b/tests/fixtures/mq_fixtures.py
@@ -1,5 +1,6 @@
 import json
 from datetime import datetime
+from datetime import timezone
 from unittest.mock import patch
 
 import pytest
@@ -87,7 +88,9 @@ def mq_create_hosts_in_all_states(mq_create_or_update_host):
 @pytest.fixture(scope="function")
 def mq_create_deleted_hosts(mq_create_or_update_host):
     with patch("app.models.datetime") as mock_datetime:
-        mock_datetime.now.return_value = datetime(year=2023, month=4, day=2, hour=1, minute=1, second=1)
+        mock_datetime.now.return_value = datetime(
+            year=2023, month=4, day=2, hour=1, minute=1, second=1, tzinfo=timezone.utc
+        )
         mock_datetime.side_effect = lambda *args, **kw: datetime(*args, **kw)
 
         staleness_timestamps = get_staleness_timestamps()
diff --git a/tests/test_xjoin.py b/tests/test_xjoin.py
index c47572e9e..1df33459c 100644
--- a/tests/test_xjoin.py
+++ b/tests/test_xjoin.py
@@ -881,7 +881,7 @@ def test_response_processed_properly(graphql_query_with_response, api_get):
                     "puptoo": {
                         "check_in_succeeded": True,
                         "last_check_in": "2020-02-10T08:07:03.354307+00:00",
-                        "stale_timestamp": "2020-02-10T08:07:03.354307+00:00",
+                        "stale_timestamp": "2020-02-11T13:07:03.354307+00:00",
                     }
                 },
                 "subscription_manager_id": None,
@@ -912,7 +912,7 @@ def test_response_processed_properly(graphql_query_with_response, api_get):
                     "yupana": {
                         "check_in_succeeded": True,
                         "last_check_in": "2020-02-10T08:07:03.354307+00:00",
-                        "stale_timestamp": "2020-02-10T08:07:03.354307+00:00",
+                        "stale_timestamp": "2020-02-11T13:07:03.354307+00:00",
                     }
                 },
                 "subscription_manager_id": None,