diff --git a/litellm/proxy/_types.py b/litellm/proxy/_types.py
index 819a38eec19..9e3cd18ff55 100644
--- a/litellm/proxy/_types.py
+++ b/litellm/proxy/_types.py
@@ -1997,7 +1997,12 @@ class TeamRequest(LiteLLMPydanticObjectBase):
 
 
 class LiteLLM_BudgetTable(LiteLLMPydanticObjectBase):
-    """Represents user-controllable params for a LiteLLM_BudgetTable record"""
+    """Represents user-controllable params for a LiteLLM_BudgetTable record.
+
+    Budget-write paths use `model_fields.keys()` on this class as an allowlist
+    for user input. Keep server-managed fields (e.g. `budget_reset_at`) on
+    `LiteLLM_BudgetTableFull` so they aren't user-settable.
+    """
 
     budget_id: Optional[str] = None
     soft_budget: Optional[float] = None
@@ -2007,7 +2012,6 @@ class LiteLLM_BudgetTable(LiteLLMPydanticObjectBase):
     rpm_limit: Optional[int] = None
     model_max_budget: Optional[dict] = None
     budget_duration: Optional[str] = None
-    budget_reset_at: Optional[datetime] = None
     allowed_models: Optional[List[str]] = (
         None  # per-member model scope; empty = inherit team models
     )
@@ -2016,8 +2020,9 @@ class LiteLLM_BudgetTable(LiteLLMPydanticObjectBase):
 
 
 class LiteLLM_BudgetTableFull(LiteLLM_BudgetTable):
-    """Represents all params for a LiteLLM_BudgetTable record"""
+    """LiteLLM_BudgetTable + server-managed fields returned on API responses."""
 
+    budget_reset_at: Optional[datetime] = None
     created_at: datetime
 
 
@@ -3696,7 +3701,12 @@ class LiteLLM_TeamMembership(LiteLLMPydanticObjectBase):
     budget_id: Optional[str] = None
     spend: Optional[float] = 0.0
     total_spend: Optional[float] = 0.0
-    litellm_budget_table: Optional[LiteLLM_BudgetTable]
+    # Union so Pydantic picks Full when data has server-managed fields
+    # (/team/info) and Base when callers/tests construct with only
+    # user-settable fields.
+    litellm_budget_table: Optional[
+        Union[LiteLLM_BudgetTableFull, LiteLLM_BudgetTable]
+    ]
 
     def safe_get_team_member_rpm_limit(self) -> Optional[int]:
         if self.litellm_budget_table is not None: