From 9783ef4e797d39e9f3b02859c8ff7ff1a4b60c25 Mon Sep 17 00:00:00 2001
From: michelligabriele <gabriele.michelli@icloud.com>
Date: Mon, 11 May 2026 21:27:36 +0200
Subject: [PATCH] fix(usage): remove timezone date-window expansion in
 aggregated dashboard

---
 .../common_daily_activity.py                  | 42 ++++++-------------
 .../test_common_daily_activity.py             | 28 +++++++++++++
 2 files changed, 40 insertions(+), 30 deletions(-)

diff --git a/litellm/proxy/management_endpoints/common_daily_activity.py b/litellm/proxy/management_endpoints/common_daily_activity.py
index d173cd745ba..7cd0134bf38 100644
--- a/litellm/proxy/management_endpoints/common_daily_activity.py
+++ b/litellm/proxy/management_endpoints/common_daily_activity.py
@@ -1,5 +1,5 @@
 import asyncio
-from datetime import datetime, timedelta
+from datetime import datetime
 from types import SimpleNamespace
 from typing import Any, Callable, Dict, List, Optional, Set, Tuple, Union
 
@@ -386,38 +386,20 @@ def _adjust_dates_for_timezone(
     timezone_offset_minutes: Optional[int],
 ) -> Tuple[str, str]:
     """
-    Adjust date range to account for timezone differences.
+    Return the date range unchanged.
 
-    The database stores dates in UTC. When a user in a different timezone
-    selects a local date range, we need to expand the UTC query range to
-    capture all records that fall within their local date range.
+    ``LiteLLM_DailyUserSpend.date`` is stored as a ``YYYY-MM-DD`` UTC string
+    at day granularity, and the UI formats ``start_date``/``end_date`` from
+    the browser's local year/month/day — so the strings already line up with
+    how rows are keyed. The previous ±1 day expansion pulled an adjacent UTC
+    day into the result set, inflating single-day totals for any non-UTC
+    user (e.g. IST users saw two days summed together).
 
-    Args:
-        start_date: Start date in YYYY-MM-DD format (user's local date)
-        end_date: End date in YYYY-MM-DD format (user's local date)
-        timezone_offset_minutes: Minutes behind UTC (positive = west of UTC)
-            This matches JavaScript's Date.getTimezoneOffset() convention.
-            For example: PST = +480 (8 hours * 60 = 480 minutes behind UTC)
-
-    Returns:
-        Tuple of (adjusted_start_date, adjusted_end_date) in YYYY-MM-DD format
+    ``timezone_offset_minutes`` is kept in the signature for compatibility
+    with callers; it is intentionally ignored.
     """
-    if timezone_offset_minutes is None or timezone_offset_minutes == 0:
-        return start_date, end_date
-
-    start = datetime.strptime(start_date, "%Y-%m-%d")
-    end = datetime.strptime(end_date, "%Y-%m-%d")
-
-    if timezone_offset_minutes > 0:
-        # West of UTC (Americas): local evening extends into next UTC day
-        # e.g., Feb 4 23:59 PST = Feb 5 07:59 UTC
-        end = end + timedelta(days=1)
-    else:
-        # East of UTC (Asia/Europe): local morning starts in previous UTC day
-        # e.g., Feb 4 00:00 IST = Feb 3 18:30 UTC
-        start = start - timedelta(days=1)
-
-    return start.strftime("%Y-%m-%d"), end.strftime("%Y-%m-%d")
+    del timezone_offset_minutes
+    return start_date, end_date
 
 
 def _build_where_conditions(
diff --git a/tests/test_litellm/proxy/management_endpoints/test_common_daily_activity.py b/tests/test_litellm/proxy/management_endpoints/test_common_daily_activity.py
index dc983aa26fd..1c8d15d9632 100644
--- a/tests/test_litellm/proxy/management_endpoints/test_common_daily_activity.py
+++ b/tests/test_litellm/proxy/management_endpoints/test_common_daily_activity.py
@@ -9,6 +9,7 @@ sys.path.insert(
 )  # Adds the parent directory to the system path
 
 from litellm.proxy.management_endpoints.common_daily_activity import (
+    _adjust_dates_for_timezone,
     _is_user_agent_tag,
     get_api_key_metadata,
     get_daily_activity,
@@ -57,6 +58,33 @@ async def test_get_daily_activity_empty_entity_id_list():
     assert where_conditions["team_id"] == {"in": []}
 
 
+@pytest.mark.parametrize(
+    "timezone_offset_minutes",
+    [
+        pytest.param(480, id="pst_west_of_utc"),
+        pytest.param(-330, id="ist_east_of_utc"),
+        pytest.param(0, id="utc"),
+        pytest.param(None, id="no_offset"),
+    ],
+)
+def test_adjust_dates_for_timezone_single_day_is_unchanged(timezone_offset_minutes):
+    # Regression: selecting a single local day in any timezone must keep the
+    # query window pinned to that one day. Previously, ±1 day was added based
+    # on the JS timezone offset, which inflated single-day totals on the
+    # aggregated usage dashboard for non-UTC users.
+    start, end = _adjust_dates_for_timezone(
+        "2026-04-15", "2026-04-15", timezone_offset_minutes
+    )
+    assert start == "2026-04-15"
+    assert end == "2026-04-15"
+
+
+def test_adjust_dates_for_timezone_multi_day_range_is_unchanged():
+    start, end = _adjust_dates_for_timezone("2026-04-10", "2026-04-15", -330)
+    assert start == "2026-04-10"
+    assert end == "2026-04-15"
+
+
 def test_is_user_agent_tag():
     """Test _is_user_agent_tag function."""
     # Test None and empty string