diff --git a/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000100_customer_budget_reference_index/migration.sql b/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000100_customer_budget_reference_index/migration.sql
new file mode 100644
index 00000000000..cadc07c0ec2
--- /dev/null
+++ b/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000100_customer_budget_reference_index/migration.sql
@@ -0,0 +1 @@
+CREATE INDEX CONCURRENTLY IF NOT EXISTS "LiteLLM_EndUserTable_budget_id_idx" ON "LiteLLM_EndUserTable" ("budget_id");
diff --git a/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000200_key_budget_reference_index/migration.sql b/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000200_key_budget_reference_index/migration.sql
new file mode 100644
index 00000000000..88af995aa61
--- /dev/null
+++ b/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000200_key_budget_reference_index/migration.sql
@@ -0,0 +1 @@
+CREATE INDEX CONCURRENTLY IF NOT EXISTS "LiteLLM_VerificationToken_budget_id_idx" ON "LiteLLM_VerificationToken" ("budget_id");
diff --git a/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000300_key_customer_budget_reference_index/migration.sql b/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000300_key_customer_budget_reference_index/migration.sql
new file mode 100644
index 00000000000..68c99aa75d3
--- /dev/null
+++ b/litellm-proxy-extras/litellm_proxy_extras/migrations/20261018000300_key_customer_budget_reference_index/migration.sql
@@ -0,0 +1 @@
+CREATE INDEX CONCURRENTLY IF NOT EXISTS "LiteLLM_VerificationToken_end_user_budget_id_idx" ON "LiteLLM_VerificationToken" USING GIN (("metadata"->'end_user_budget_id') jsonb_path_ops);
diff --git a/litellm-proxy-extras/litellm_proxy_extras/schema.prisma b/litellm-proxy-extras/litellm_proxy_extras/schema.prisma
index 83a0e6f9e05..9bdb51d1ea7 100644
--- a/litellm-proxy-extras/litellm_proxy_extras/schema.prisma
+++ b/litellm-proxy-extras/litellm_proxy_extras/schema.prisma
@@ -563,6 +563,7 @@ model LiteLLM_VerificationToken {
 
     // SELECT ... FROM "public"."LiteLLM_VerificationToken" WHERE (("public"."LiteLLM_VerificationToken"."expires" IS NULL OR "public"."LiteLLM_VerificationToken"."expires" > $1) AND "public"."LiteLLM_VerificationToken"."budget_reset_at" < $2) OFFSET $3
     @@index([budget_reset_at, expires])
+    @@index([budget_id])
 }
 
 model LiteLLM_JWTKeyMapping {
@@ -678,6 +679,7 @@ model LiteLLM_EndUserTable {
   litellm_budget_table LiteLLM_BudgetTable?   @relation(fields: [budget_id], references: [budget_id])
   object_permission LiteLLM_ObjectPermissionTable?   @relation(fields: [object_permission_id], references: [object_permission_id])
   blocked Boolean @default(false)
+    @@index([budget_id])
 }
 
 // Budget and shared spend for a model access group. The groups themselves are not rows anywhere:
diff --git a/litellm/proxy/management_endpoints/customer_endpoints.py b/litellm/proxy/management_endpoints/customer_endpoints.py
index 65ce424c5e4..90afe9faaa4 100644
--- a/litellm/proxy/management_endpoints/customer_endpoints.py
+++ b/litellm/proxy/management_endpoints/customer_endpoints.py
@@ -76,7 +76,8 @@ _CUSTOMER_SHARED_BUDGET_SQL: Final = """
 SELECT "budget_id" FROM "LiteLLM_BudgetTable" WHERE "budget_id" = $1 AND EXISTS (
     SELECT 1 FROM "LiteLLM_EndUserTable" WHERE "budget_id" = $1 AND "user_id" <> $2
     UNION ALL SELECT 1 FROM "LiteLLM_VerificationToken" WHERE "budget_id" = $1
-        OR "metadata"->>'end_user_budget_id' = $1
+        OR (("metadata"->'end_user_budget_id') @> to_jsonb($1::text)
+            AND jsonb_typeof("metadata"->'end_user_budget_id') = 'string')
     UNION ALL SELECT 1 FROM "LiteLLM_OrganizationTable" WHERE "budget_id" = $1
     UNION ALL SELECT 1 FROM "LiteLLM_ProjectTable" WHERE "budget_id" = $1
     UNION ALL SELECT 1 FROM "LiteLLM_TagTable" WHERE "budget_id" = $1
diff --git a/litellm/proxy/schema.prisma b/litellm/proxy/schema.prisma
index 83a0e6f9e05..9bdb51d1ea7 100644
--- a/litellm/proxy/schema.prisma
+++ b/litellm/proxy/schema.prisma
@@ -563,6 +563,7 @@ model LiteLLM_VerificationToken {
 
     // SELECT ... FROM "public"."LiteLLM_VerificationToken" WHERE (("public"."LiteLLM_VerificationToken"."expires" IS NULL OR "public"."LiteLLM_VerificationToken"."expires" > $1) AND "public"."LiteLLM_VerificationToken"."budget_reset_at" < $2) OFFSET $3
     @@index([budget_reset_at, expires])
+    @@index([budget_id])
 }
 
 model LiteLLM_JWTKeyMapping {
@@ -678,6 +679,7 @@ model LiteLLM_EndUserTable {
   litellm_budget_table LiteLLM_BudgetTable?   @relation(fields: [budget_id], references: [budget_id])
   object_permission LiteLLM_ObjectPermissionTable?   @relation(fields: [object_permission_id], references: [object_permission_id])
   blocked Boolean @default(false)
+    @@index([budget_id])
 }
 
 // Budget and shared spend for a model access group. The groups themselves are not rows anywhere:
diff --git a/schema.prisma b/schema.prisma
index 83a0e6f9e05..9bdb51d1ea7 100644
--- a/schema.prisma
+++ b/schema.prisma
@@ -563,6 +563,7 @@ model LiteLLM_VerificationToken {
 
     // SELECT ... FROM "public"."LiteLLM_VerificationToken" WHERE (("public"."LiteLLM_VerificationToken"."expires" IS NULL OR "public"."LiteLLM_VerificationToken"."expires" > $1) AND "public"."LiteLLM_VerificationToken"."budget_reset_at" < $2) OFFSET $3
     @@index([budget_reset_at, expires])
+    @@index([budget_id])
 }
 
 model LiteLLM_JWTKeyMapping {
@@ -678,6 +679,7 @@ model LiteLLM_EndUserTable {
   litellm_budget_table LiteLLM_BudgetTable?   @relation(fields: [budget_id], references: [budget_id])
   object_permission LiteLLM_ObjectPermissionTable?   @relation(fields: [object_permission_id], references: [object_permission_id])
   blocked Boolean @default(false)
+    @@index([budget_id])
 }
 
 // Budget and shared spend for a model access group. The groups themselves are not rows anywhere:
diff --git a/tests/integration/database/migrations/test_customer_budget_reference_lookup.py b/tests/integration/database/migrations/test_customer_budget_reference_lookup.py
new file mode 100644
index 00000000000..1717ee59f39
--- /dev/null
+++ b/tests/integration/database/migrations/test_customer_budget_reference_lookup.py
@@ -0,0 +1,89 @@
+import os
+from pathlib import Path
+from typing import Final
+
+import psycopg
+from psycopg import sql
+from pydantic import BaseModel, Field, TypeAdapter
+
+from litellm.proxy.management_endpoints.customer_endpoints import _CUSTOMER_SHARED_BUDGET_SQL
+
+_REPOSITORY: Final = Path(__file__).resolve().parents[4]
+_MIGRATIONS: Final = _REPOSITORY / "litellm-proxy-extras" / "litellm_proxy_extras" / "migrations"
+_INDEX_MIGRATIONS: Final = (
+    "20261018000100_customer_budget_reference_index",
+    "20261018000200_key_budget_reference_index",
+    "20261018000300_key_customer_budget_reference_index",
+)
+_REFERENCE_TABLES: Final = (
+    "LiteLLM_OrganizationTable",
+    "LiteLLM_ProjectTable",
+    "LiteLLM_TagTable",
+    "LiteLLM_ModelAccessGroupBudgetTable",
+    "LiteLLM_TeamMembership",
+    "LiteLLM_OrganizationMembership",
+    "LiteLLM_TeamTable",
+)
+
+
+class _PlanNode(BaseModel):
+    rows: float = Field(default=0, alias="Actual Rows")
+    removed: float = Field(default=0, alias="Rows Removed by Filter")
+    loops: float = Field(default=0, alias="Actual Loops")
+    plans: tuple["_PlanNode", ...] = Field(default=(), alias="Plans")
+
+    def examined_rows(self) -> float:
+        return (self.rows + self.removed) * self.loops + sum(plan.examined_rows() for plan in self.plans)
+
+
+class _QueryPlan(BaseModel):
+    plan: _PlanNode = Field(alias="Plan")
+
+
+def test_customer_budget_guard_keeps_generic_plan_work_bounded() -> None:
+    with psycopg.connect(os.environ["DATABASE_URL"], autocommit=True) as connection:
+        connection.execute('CREATE TABLE "LiteLLM_BudgetTable" (budget_id text PRIMARY KEY)')
+        connection.execute('CREATE TABLE "LiteLLM_EndUserTable" (user_id text PRIMARY KEY, budget_id text)')
+        connection.execute(
+            'CREATE TABLE "LiteLLM_VerificationToken" (token text PRIMARY KEY, budget_id text, metadata jsonb)'
+        )
+        for table in _REFERENCE_TABLES:
+            connection.execute(
+                sql.SQL("CREATE TABLE {} (budget_id text, metadata jsonb)").format(sql.Identifier(table))
+            )
+        connection.execute("INSERT INTO \"LiteLLM_BudgetTable\" SELECT 'budget-'||n FROM generate_series(0,500) n")
+        connection.execute(
+            "INSERT INTO \"LiteLLM_EndUserTable\" SELECT 'customer-'||n,'budget-'||n FROM generate_series(0,500) n"
+        )
+        key_count: Final = 50_000
+        connection.execute(
+            "INSERT INTO \"LiteLLM_VerificationToken\" SELECT 'key-'||n,NULL,"
+            "jsonb_build_object('end_user_budget_id','unrelated-budget') FROM generate_series(1,%s) n",
+            (key_count,),
+        )
+        for migration in _INDEX_MIGRATIONS:
+            connection.execute((_MIGRATIONS / migration / "migration.sql").read_text())
+        connection.execute("ANALYZE")
+        connection.execute("SET plan_cache_mode = force_generic_plan")
+        connection.execute("PREPARE guard(text,text) AS " + _CUSTOMER_SHARED_BUDGET_SQL)
+        plan_row: Final = connection.execute(
+            "EXPLAIN (ANALYZE, FORMAT JSON) EXECUTE guard('budget-0','customer-0')"
+        ).fetchone()
+        assert plan_row is not None
+        plan: Final = TypeAdapter(tuple[_QueryPlan, ...]).validate_python(plan_row[0])[0].plan
+        assert plan.examined_rows() < key_count / 100
+        assert connection.execute("EXECUTE guard('budget-0','customer-0')").fetchall() == []
+        for metadata in ('{"end_user_budget_id": ["budget-0"]}', '{"end_user_budget_id": null}'):
+            connection.execute(
+                "INSERT INTO \"LiteLLM_VerificationToken\" VALUES ('malformed',NULL,%s::jsonb)", (metadata,)
+            )
+            assert connection.execute("EXECUTE guard('budget-0','customer-0')").fetchall() == []
+            connection.execute("DELETE FROM \"LiteLLM_VerificationToken\" WHERE token='malformed'")
+        connection.execute(
+            'INSERT INTO "LiteLLM_VerificationToken" VALUES '
+            "('metadata-budget',NULL,jsonb_build_object('end_user_budget_id','budget-0'))"
+        )
+        assert connection.execute("EXECUTE guard('budget-0','customer-0')").fetchall() == [("budget-0",)]
+        connection.execute("DELETE FROM \"LiteLLM_VerificationToken\" WHERE token='metadata-budget'")
+        connection.execute("INSERT INTO \"LiteLLM_VerificationToken\" VALUES ('direct-budget','budget-0','{}')")
+        assert connection.execute("EXECUTE guard('budget-0','customer-0')").fetchall() == [("budget-0",)]
diff --git a/tests/unit/proxy/management_endpoints/test_customer_endpoints.py b/tests/unit/proxy/management_endpoints/test_customer_endpoints.py
index 32515d649bc..50fb179da09 100644
--- a/tests/unit/proxy/management_endpoints/test_customer_endpoints.py
+++ b/tests/unit/proxy/management_endpoints/test_customer_endpoints.py
@@ -1318,7 +1318,10 @@ class _CustomerBatchDatabase:
                 [
                     dict(row)
                     for row in database.execute(
-                        query, {str(index): value for index, value in enumerate(parameters, 1)}
+                        query.replace("@> to_jsonb($1::text)", "= json_quote($1)")
+                        .replace("jsonb_typeof", "json_type")
+                        .replace("= 'string'", "= 'text'"),
+                        {str(index): value for index, value in enumerate(parameters, 1)},
                     ).fetchall()
                 ]
             )