diff --git a/backend/crates/gateway-admin/src/ports/store.rs b/backend/crates/gateway-admin/src/ports/store.rs
index 411f0072d..7a5f6eda9 100644
--- a/backend/crates/gateway-admin/src/ports/store.rs
+++ b/backend/crates/gateway-admin/src/ports/store.rs
@@ -218,7 +218,12 @@ pub trait ClientKeyStore: Send + Sync {
 /// 用量、趋势、诊断与运维错误的只读能力。
 #[async_trait]
 pub trait ObservabilityStore: Send + Sync {
-    async fn dashboard_summary(&self, range: TimeRange) -> AdminStoreResult<DashboardObservation>;
+    /// 返回历史统计区间和指定观测时刻下的实时账号状态。
+    async fn dashboard_summary(
+        &self,
+        range: TimeRange,
+        observed_at: DateTime<Utc>,
+    ) -> AdminStoreResult<DashboardObservation>;
 
     /// 返回 Dashboard 可选的实时槽位事实。
     ///
diff --git a/backend/crates/gateway-admin/src/use_case/observability.rs b/backend/crates/gateway-admin/src/use_case/observability.rs
index a116f81b6..8939e6426 100644
--- a/backend/crates/gateway-admin/src/use_case/observability.rs
+++ b/backend/crates/gateway-admin/src/use_case/observability.rs
@@ -98,10 +98,11 @@ impl ObservabilityService for DefaultObservabilityService {
         range: TimeRange,
         kind: TrendKind,
     ) -> Result<DashboardResult, AdminError> {
+        let observed_at = Utc::now();
         let (mut observation, settings, runtime_slots) = futures::try_join!(
-            self.store.dashboard_summary(range),
+            self.store.dashboard_summary(range, observed_at),
             self.settings.load_runtime_settings(),
-            self.store.dashboard_runtime_slots(range.end),
+            self.store.dashboard_runtime_slots(observed_at),
         )
         .map_err(|error| map_store_error(error, "dashboard"))?;
         self.enrich_billing(&mut observation.recent_requests);
diff --git a/backend/crates/gateway-admin/tests/use_case/mod.rs b/backend/crates/gateway-admin/tests/use_case/mod.rs
index c7b1b196e..cda8de9db 100644
--- a/backend/crates/gateway-admin/tests/use_case/mod.rs
+++ b/backend/crates/gateway-admin/tests/use_case/mod.rs
@@ -14,6 +14,7 @@ use std::{
 };
 
 use async_trait::async_trait;
+use chrono::{DateTime, Utc};
 use futures::future::BoxFuture;
 use gateway_admin::{
     AdminConfig, AdminServices, InitialAdminPassword,
@@ -391,7 +392,11 @@ impl ClientKeyStore for UnavailableStore {
 
 #[async_trait]
 impl ObservabilityStore for UnavailableStore {
-    async fn dashboard_summary(&self, _: TimeRange) -> AdminStoreResult<DashboardObservation> {
+    async fn dashboard_summary(
+        &self,
+        _: TimeRange,
+        _: DateTime<Utc>,
+    ) -> AdminStoreResult<DashboardObservation> {
         Err(unavailable("dashboard"))
     }
 
diff --git a/backend/crates/gateway-admin/tests/use_case/observability.rs b/backend/crates/gateway-admin/tests/use_case/observability.rs
index 3deec85ab..15a91e5d6 100644
--- a/backend/crates/gateway-admin/tests/use_case/observability.rs
+++ b/backend/crates/gateway-admin/tests/use_case/observability.rs
@@ -200,6 +200,25 @@ async fn dashboard_summary_should_project_rebuildable_runtime_slots() {
     assert_eq!(capacity.available_slots, Some(1));
 }
 
+#[tokio::test]
+async fn dashboard_summary_should_share_one_current_observation_time_across_runtime_facts() {
+    let historical_end = Utc::now() - Duration::hours(1);
+    let store = Arc::new(FixtureObservabilityStore::new(observation_range(
+        historical_end,
+    )));
+    let services = observability_services(store.clone()).await;
+
+    services
+        .observability()
+        .dashboard_summary(observation_range(historical_end), TrendKind::Usage)
+        .await
+        .expect("dashboard summary");
+
+    let (summary_observed_at, slots_observed_at) = store.observed_times();
+    assert_eq!(summary_observed_at, slots_observed_at);
+    assert!(summary_observed_at.is_some_and(|value| value > historical_end));
+}
+
 #[tokio::test]
 async fn observability_services_should_calculate_usage_insights_and_diagnostic_shares() {
     let now = Utc::now();
@@ -394,6 +413,8 @@ struct FixtureObservabilityStore {
     calculated_billing_facts: Mutex<Vec<UsageCalculatedBillingFact>>,
     diagnostics: Mutex<Vec<DiagnosticObservation>>,
     runtime_slots: Mutex<Option<DashboardRuntimeSlots>>,
+    summary_observed_at: Mutex<Option<DateTime<Utc>>>,
+    slots_observed_at: Mutex<Option<DateTime<Utc>>>,
     usage_records: Mutex<Vec<UsageRecord>>,
 }
 
@@ -410,6 +431,8 @@ impl FixtureObservabilityStore {
             calculated_billing_facts: Mutex::new(Vec::new()),
             diagnostics: Mutex::new(Vec::new()),
             runtime_slots: Mutex::new(None),
+            summary_observed_at: Mutex::new(None),
+            slots_observed_at: Mutex::new(None),
             usage_records: Mutex::new(Vec::new()),
         }
     }
@@ -437,6 +460,16 @@ impl FixtureObservabilityStore {
         *self.runtime_slots.lock().expect("runtime slots") = runtime_slots;
     }
 
+    fn observed_times(&self) -> (Option<DateTime<Utc>>, Option<DateTime<Utc>>) {
+        (
+            *self
+                .summary_observed_at
+                .lock()
+                .expect("summary observed at"),
+            *self.slots_observed_at.lock().expect("slots observed at"),
+        )
+    }
+
     fn replace_usage_records(&self, records: Vec<UsageRecord>) {
         *self.usage_records.lock().expect("usage records") = records;
     }
@@ -444,7 +477,15 @@ impl FixtureObservabilityStore {
 
 #[async_trait]
 impl ObservabilityStore for FixtureObservabilityStore {
-    async fn dashboard_summary(&self, range: TimeRange) -> AdminStoreResult<DashboardObservation> {
+    async fn dashboard_summary(
+        &self,
+        range: TimeRange,
+        observed_at: DateTime<Utc>,
+    ) -> AdminStoreResult<DashboardObservation> {
+        *self
+            .summary_observed_at
+            .lock()
+            .expect("summary observed at") = Some(observed_at);
         Ok(DashboardObservation {
             range,
             requests: RequestMetrics::default(),
@@ -459,8 +500,9 @@ impl ObservabilityStore for FixtureObservabilityStore {
 
     async fn dashboard_runtime_slots(
         &self,
-        _: DateTime<Utc>,
+        observed_at: DateTime<Utc>,
     ) -> AdminStoreResult<Option<DashboardRuntimeSlots>> {
+        *self.slots_observed_at.lock().expect("slots observed at") = Some(observed_at);
         Ok(*self.runtime_slots.lock().expect("runtime slots"))
     }
 
diff --git a/backend/crates/gateway-api/tests/admin/mod.rs b/backend/crates/gateway-api/tests/admin/mod.rs
index 08c148842..eab9d45d5 100644
--- a/backend/crates/gateway-api/tests/admin/mod.rs
+++ b/backend/crates/gateway-api/tests/admin/mod.rs
@@ -7,7 +7,7 @@ use std::{
 };
 
 use async_trait::async_trait;
-use chrono::{Duration, Utc};
+use chrono::{DateTime, Duration, Utc};
 use futures::future::BoxFuture;
 use gateway_admin::{
     AdminConfig, AdminServices, InitialAdminPassword,
@@ -528,7 +528,11 @@ impl AccountStore for UnusedStore {
 
 #[async_trait]
 impl ObservabilityStore for UnusedStore {
-    async fn dashboard_summary(&self, range: TimeRange) -> AdminStoreResult<DashboardObservation> {
+    async fn dashboard_summary(
+        &self,
+        range: TimeRange,
+        _: DateTime<Utc>,
+    ) -> AdminStoreResult<DashboardObservation> {
         *self
             .dashboard_summary_range
             .lock()
diff --git a/backend/crates/gateway-store/src/postgres/observability/admin_adapter.rs b/backend/crates/gateway-store/src/postgres/observability/admin_adapter.rs
index 98b438f66..fa4171470 100644
--- a/backend/crates/gateway-store/src/postgres/observability/admin_adapter.rs
+++ b/backend/crates/gateway-store/src/postgres/observability/admin_adapter.rs
@@ -98,6 +98,7 @@ impl ObservabilityRepository for PgObservabilityRepository {
     async fn dashboard_summary(
         &self,
         range: ObservabilityRange,
+        observed_at: DateTime<Utc>,
     ) -> StoreResult<DashboardObservation> {
         let filter = UsageRecordFilter::default();
         let account_usage_range = ObservabilityRange::new(
@@ -123,7 +124,7 @@ impl ObservabilityRepository for PgObservabilityRepository {
             attempt_metrics(&self.pool, range, &filter),
             dashboard_totals(&self.pool),
         )?;
-        let (provider_accounts, _) = self.account_status_snapshot(range.end).await?;
+        let (provider_accounts, _) = self.account_status_snapshot(observed_at).await?;
         let (trend, account_usage, recent_requests) = futures::try_join!(
             request_metric_series(&self.pool, range, &filter),
             provider_account_usage(&self.pool, account_usage_query),
@@ -215,10 +216,11 @@ impl AdminObservabilityStore for PgAdminObservabilityStore {
     async fn dashboard_summary(
         &self,
         range: admin_observability::TimeRange,
+        observed_at: DateTime<Utc>,
     ) -> AdminStoreResult<admin_observability::DashboardObservation> {
         let observation = self
             .repository
-            .dashboard_summary(store_range(range)?)
+            .dashboard_summary(store_range(range)?, observed_at)
             .await
             .map_err(observability_error)?;
         admin_dashboard_observation(observation)
diff --git a/backend/crates/gateway-store/src/postgres/observability/model.rs b/backend/crates/gateway-store/src/postgres/observability/model.rs
index 33d8083d3..cb43aac33 100644
--- a/backend/crates/gateway-store/src/postgres/observability/model.rs
+++ b/backend/crates/gateway-store/src/postgres/observability/model.rs
@@ -683,6 +683,7 @@ pub trait ObservabilityRepository: Send + Sync {
     async fn dashboard_summary(
         &self,
         range: ObservabilityRange,
+        observed_at: DateTime<Utc>,
     ) -> StoreResult<DashboardObservation>;
     async fn dashboard_trend(
         &self,
diff --git a/backend/crates/gateway-store/tests/postgres/observability.rs b/backend/crates/gateway-store/tests/postgres/observability.rs
index c506487bc..ab23dc1fa 100644
--- a/backend/crates/gateway-store/tests/postgres/observability.rs
+++ b/backend/crates/gateway-store/tests/postgres/observability.rs
@@ -166,7 +166,7 @@ async fn dashboard_account_metrics_should_partition_account_statuses() {
         .expect("dashboard range");
 
     let metrics = repository
-        .dashboard_summary(range)
+        .dashboard_summary(range, now)
         .await
         .expect("dashboard summary")
         .provider_accounts;
@@ -252,7 +252,7 @@ async fn dashboard_account_metrics_with_cooldowns_should_only_reclassify_eligibl
         .expect("dashboard range");
 
     let metrics = repository
-        .dashboard_summary(range)
+        .dashboard_summary(range, now)
         .await
         .expect("dashboard summary")
         .provider_accounts;
@@ -416,7 +416,7 @@ async fn admin_observability_adapter_preserves_utc_queries_metrics_costs_and_det
     let store = PgAdminObservabilityStore::new(database.pool.clone(), None, None);
 
     let dashboard = store
-        .dashboard_summary(range)
+        .dashboard_summary(range, now)
         .await
         .expect("admin dashboard summary");
     assert_eq!(dashboard.range, range);
@@ -714,7 +714,7 @@ async fn dashboard_summary_totals_include_history_outside_selected_range() {
     let repository = PgObservabilityRepository::new(database.pool.clone(), None);
 
     let dashboard = repository
-        .dashboard_summary(range)
+        .dashboard_summary(range, now)
         .await
         .expect("dashboard summary");
     assert_eq!(dashboard.requests.request_count, 2);
@@ -753,7 +753,7 @@ async fn observability_queries_preserve_request_account_cost_and_diagnostic_fact
     let repository = PgObservabilityRepository::new(database.pool.clone(), None);
 
     let dashboard = repository
-        .dashboard_summary(range)
+        .dashboard_summary(range, now)
         .await
         .expect("dashboard summary");
     assert_eq!(dashboard.requests.request_count, 3);