diff --git a/backend/src/services/clientTarget.service.ts b/backend/src/services/clientTarget.service.ts
index db6a160..f3b6a0d 100644
--- a/backend/src/services/clientTarget.service.ts
+++ b/backend/src/services/clientTarget.service.ts
@@ -212,6 +212,8 @@ export interface ClientTargetWithBalance {
   currentPeriodTrackedSeconds: number;
   currentPeriodTargetSeconds: number;
   periods: PeriodBalance[];
+  /** True when an active timer is running for a project belonging to this client. */
+  hasOngoingTimer: boolean;
 }
 
 // ---------------------------------------------------------------------------
@@ -405,6 +407,32 @@ export class ClientTargetService {
     const overallEnd = periods[periods.length - 1].end;
     const today = new Date().toISOString().split('T')[0];
 
+    // Fetch active timer for this user (if any) and check if it belongs to this client
+    const ongoingTimer = await prisma.ongoingTimer.findUnique({
+      where: { userId: target.userId },
+      include: { project: { select: { clientId: true } } },
+    });
+
+    // Elapsed seconds from the active timer attributed to this client target.
+    // We only count it if the timer has a project assigned and that project
+    // belongs to the same client as this target.
+    let ongoingTimerSeconds = 0;
+    let ongoingTimerPeriodStart: string | null = null;
+
+    if (
+      ongoingTimer &&
+      ongoingTimer.projectId !== null &&
+      ongoingTimer.project?.clientId === target.clientId
+    ) {
+      ongoingTimerSeconds = Math.floor(
+        (Date.now() - ongoingTimer.startTime.getTime()) / 1000,
+      );
+      // Determine which period the timer's start time falls into
+      const timerDateStr = ongoingTimer.startTime.toISOString().split('T')[0];
+      const timerPeriod = getPeriodForDate(timerDateStr, periodType);
+      ongoingTimerPeriodStart = timerPeriod.start;
+    }
+
     // Fetch all time tracked for this client across the full range in one query
     type TrackedRow = { period_start: string; tracked_seconds: bigint };
 
@@ -489,7 +517,13 @@ export class ClientTargetService {
         ? computePeriodTargetHours(period, startDateStr, target.targetHours, periodType)
         : target.targetHours;
 
-      const trackedSeconds = trackedByPeriod.get(period.start) ?? 0;
+      // Add ongoing timer seconds to the period it started in (if it belongs to this client)
+      const timerContribution =
+        ongoingTimerPeriodStart !== null && period.start === ongoingTimerPeriodStart
+          ? ongoingTimerSeconds
+          : 0;
+
+      const trackedSeconds = (trackedByPeriod.get(period.start) ?? 0) + timerContribution;
       const correctionHours = correctionsByPeriod.get(period.start) ?? 0;
 
       const isOngoing = cmpDate(period.start, today) <= 0 && cmpDate(today, period.end) <= 0;
@@ -574,6 +608,7 @@ export class ClientTargetService {
         ? Math.round(currentPeriod.targetHours * 3600)
         : Math.round(target.targetHours * 3600),
       periods: periodBalances,
+      hasOngoingTimer: ongoingTimerSeconds > 0,
     };
   }
 
@@ -594,6 +629,7 @@ export class ClientTargetService {
       currentPeriodTrackedSeconds: 0,
       currentPeriodTargetSeconds: Math.round(target.targetHours * 3600),
       periods: [],
+      hasOngoingTimer: false,
     };
   }
 }
diff --git a/frontend/src/hooks/useClientTargets.ts b/frontend/src/hooks/useClientTargets.ts
index 4c243e9..65ee5b2 100644
--- a/frontend/src/hooks/useClientTargets.ts
+++ b/frontend/src/hooks/useClientTargets.ts
@@ -1,5 +1,6 @@
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { clientTargetsApi } from '@/api/clientTargets';
+import { useTimer } from '@/contexts/TimerContext';
 import type {
   CreateClientTargetInput,
   UpdateClientTargetInput,
@@ -8,10 +9,13 @@ import type {
 
 export function useClientTargets() {
   const queryClient = useQueryClient();
+  const { ongoingTimer } = useTimer();
 
   const { data: targets, isLoading, error } = useQuery({
     queryKey: ['clientTargets'],
     queryFn: clientTargetsApi.getAll,
+    // Poll every 30 s while a timer is running so the balance stays current
+    refetchInterval: ongoingTimer ? 30_000 : false,
   });
 
   const createTarget = useMutation({
diff --git a/frontend/src/pages/ClientsPage.tsx b/frontend/src/pages/ClientsPage.tsx
index 6dae4a1..7d4ee7a 100644
--- a/frontend/src/pages/ClientsPage.tsx
+++ b/frontend/src/pages/ClientsPage.tsx
@@ -316,6 +316,12 @@ function ClientTargetPanel({
             <span className="font-medium">{target!.targetHours}h</span>/{periodLabel}
           </span>
           <span className={`text-xs font-semibold ${balance.color}`}>{balance.text}</span>
+          {target!.hasOngoingTimer && (
+            <span
+              className="inline-block h-2 w-2 rounded-full bg-green-500 animate-pulse"
+              title="Timer running — balance updates every 30 s"
+            />
+          )}
         </div>
         <div className="flex items-center gap-1">
           <button
diff --git a/frontend/src/pages/DashboardPage.tsx b/frontend/src/pages/DashboardPage.tsx
index ebce84c..96d2c83 100644
--- a/frontend/src/pages/DashboardPage.tsx
+++ b/frontend/src/pages/DashboardPage.tsx
@@ -132,19 +132,27 @@ export function DashboardPage() {
                       </p>
                   </div>
                   <div className="text-right">
-                    <p
-                      className={`text-sm font-bold ${
-                        isEven
-                          ? 'text-gray-500'
-                          : isOver
-                          ? 'text-green-600'
-                          : 'text-red-600'
-                      }`}
-                    >
-                      {isEven
-                        ? '±0'
-                        : (isOver ? '+' : '−') + formatDurationHoursMinutes(absBalance)}
-                    </p>
+                    <div className="flex items-center justify-end gap-1.5">
+                      {target.hasOngoingTimer && (
+                        <span
+                          className="inline-block h-2 w-2 rounded-full bg-green-500 animate-pulse"
+                          title="Timer running — balance updates every 30 s"
+                        />
+                      )}
+                      <p
+                        className={`text-sm font-bold ${
+                          isEven
+                            ? 'text-gray-500'
+                            : isOver
+                            ? 'text-green-600'
+                            : 'text-red-600'
+                        }`}
+                      >
+                        {isEven
+                          ? '±0'
+                          : (isOver ? '+' : '−') + formatDurationHoursMinutes(absBalance)}
+                      </p>
+                    </div>
                     <p className="text-xs text-gray-400">running balance</p>
                   </div>
                 </div>
diff --git a/frontend/src/types/index.ts b/frontend/src/types/index.ts
index 3d309f1..65c070b 100644
--- a/frontend/src/types/index.ts
+++ b/frontend/src/types/index.ts
@@ -186,6 +186,8 @@ export interface ClientTargetWithBalance {
   currentPeriodTrackedSeconds: number;
   currentPeriodTargetSeconds: number;
   periods: PeriodBalance[];
+  /** True when an active timer for a project belonging to this client is running. */
+  hasOngoingTimer: boolean;
 }
 
 export interface CreateClientTargetInput {