diff --git a/client/src/pages/ProfitAnalysis.tsx b/client/src/pages/ProfitAnalysis.tsx
index 2b27aeb..3f3511f 100644
--- a/client/src/pages/ProfitAnalysis.tsx
+++ b/client/src/pages/ProfitAnalysis.tsx
@@ -29,35 +29,9 @@ const ProfitAnalysis = () => {
     return ProfitAnalysisService.filterOrdersByDateRange(orders || [], dateRange);
   }, [orders, dateRange]);
 
-  // Filter expenses by the same date range
+  // Filter expenses by the same date range as orders (shared logic)
   const filteredExpenses = useMemo(() => {
-    if (!expenses || dateRange === 'all') return expenses || [];
-    
-    const now = new Date();
-    return expenses.filter(expense => {
-      const expenseDate = new Date(expense.date);
-      
-      // Handle specific month format (e.g., "2025-07" for July 2025)
-      if (dateRange.match(/^\d{4}-\d{2}$/)) {
-        const [year, month] = dateRange.split('-');
-        return expenseDate.getFullYear() === parseInt(year) && 
-               expenseDate.getMonth() === parseInt(month) - 1;
-      }
-      
-      // Handle preset ranges
-      switch (dateRange) {
-        case 'week':
-          return expenseDate >= new Date(now.getTime() - 7 * 24 * 60 * 60 * 1000);
-        case 'month':
-          return expenseDate >= new Date(now.getTime() - 30 * 24 * 60 * 60 * 1000);
-        case 'quarter':
-          return expenseDate >= new Date(now.getTime() - 90 * 24 * 60 * 60 * 1000);
-        case 'year':
-          return expenseDate >= new Date(now.getTime() - 365 * 24 * 60 * 60 * 1000);
-        default:
-          return true;
-      }
-    });
+    return ProfitAnalysisService.filterExpensesByDateRange(expenses || [], dateRange);
   }, [expenses, dateRange]);
 
   // Calculate profit metrics using the service with expenses
diff --git a/client/src/utils/profitAnalysisService.ts b/client/src/utils/profitAnalysisService.ts
index d36bd98..8be732e 100644
--- a/client/src/utils/profitAnalysisService.ts
+++ b/client/src/utils/profitAnalysisService.ts
@@ -258,65 +258,67 @@ export class ProfitAnalysisService {
     return results;
   }
 
+  /**
+   * Whether a date falls within a date-range token. Single source of truth so
+   * orders and expenses are always filtered identically (months, quarters,
+   * years, custom ranges, and legacy presets).
+   */
+  static isInDateRange(dateValue: string | Date, dateRange: string): boolean {
+    if (dateRange === 'all') return true;
+
+    const date = new Date(dateValue);
+
+    // Specific month format (e.g., "2025-07")
+    if (dateRange.match(/^\d{4}-\d{2}$/)) {
+      const [year, month] = dateRange.split('-');
+      return date.getFullYear() === parseInt(year) && date.getMonth() === parseInt(month) - 1;
+    }
+
+    // Quarter format (e.g., "2025-Q1")
+    if (dateRange.match(/^\d{4}-Q[1-4]$/)) {
+      const [year, quarter] = dateRange.split('-Q');
+      return date.getFullYear() === parseInt(year) &&
+             Math.floor(date.getMonth() / 3) + 1 === parseInt(quarter);
+    }
+
+    // Year format (e.g., "2025")
+    if (dateRange.match(/^\d{4}$/)) {
+      return date.getFullYear() === parseInt(dateRange);
+    }
+
+    // Custom range (e.g., "2025-01-01_2025-12-31")
+    if (dateRange.includes('_')) {
+      const [startDate, endDate] = dateRange.split('_');
+      const end = new Date(endDate);
+      end.setHours(23, 59, 59, 999);
+      return date >= new Date(startDate) && date <= end;
+    }
+
+    // Legacy preset ranges
+    const daysDiff = (Date.now() - date.getTime()) / (24 * 60 * 60 * 1000);
+    switch (dateRange) {
+      case 'week': return daysDiff >= 0 && daysDiff <= 7;
+      case 'month': return daysDiff >= 0 && daysDiff <= 30;
+      case 'quarter': return daysDiff >= 0 && daysDiff <= 90;
+      case 'year': return daysDiff >= 0 && daysDiff <= 365;
+      default: return true;
+    }
+  }
+
   /**
    * Filter orders by date range
    */
   static filterOrdersByDateRange(orders: Order[], dateRange: string): Order[] {
     if (dateRange === 'all' || !orders) return orders;
+    return orders.filter(order => this.isInDateRange(order.dateOrdered, dateRange));
+  }
 
-    const now = new Date();
-    const filteredOrders = orders.filter(order => {
-      const orderDate = new Date(order.dateOrdered);
-      
-      // Handle specific month format (e.g., "2025-07" for July 2025)
-      if (dateRange.match(/^\d{4}-\d{2}$/)) {
-        const [year, month] = dateRange.split('-');
-        return orderDate.getFullYear() === parseInt(year) && 
-               orderDate.getMonth() === parseInt(month) - 1;
-      }
-      
-      // Handle quarter format (e.g., "2025-Q1")
-      if (dateRange.match(/^\d{4}-Q[1-4]$/)) {
-        const [year, quarter] = dateRange.split('-Q');
-        const targetYear = parseInt(year);
-        const targetQuarter = parseInt(quarter);
-        const orderYear = orderDate.getFullYear();
-        const orderQuarter = Math.floor(orderDate.getMonth() / 3) + 1;
-        return orderYear === targetYear && orderQuarter === targetQuarter;
-      }
-      
-      // Handle year format (e.g., "2025")
-      if (dateRange.match(/^\d{4}$/)) {
-        return orderDate.getFullYear() === parseInt(dateRange);
-      }
-      
-      // Handle custom date range format (e.g., "2025-01-01_2025-12-31")
-      if (dateRange.includes('_')) {
-        const [startDate, endDate] = dateRange.split('_');
-        const start = new Date(startDate);
-        const end = new Date(endDate);
-        return orderDate >= start && orderDate <= end;
-      }
-      
-      // Handle legacy preset ranges
-      const timeDiff = now.getTime() - orderDate.getTime();
-      const daysDiff = timeDiff / (24 * 60 * 60 * 1000);
-
-      switch (dateRange) {
-        case 'week':
-          return daysDiff >= 0 && daysDiff <= 7;
-        case 'month':
-          return daysDiff >= 0 && daysDiff <= 30;
-        case 'quarter':
-          return daysDiff >= 0 && daysDiff <= 90;
-        case 'year':
-          return daysDiff >= 0 && daysDiff <= 365;
-        default:
-          return true;
-      }
-    });
-
-    return filteredOrders;
+  /**
+   * Filter expenses by date range (same logic as orders)
+   */
+  static filterExpensesByDateRange(expenses: Expense[], dateRange: string): Expense[] {
+    if (dateRange === 'all' || !expenses) return expenses;
+    return expenses.filter(expense => this.isInDateRange(expense.date, dateRange));
   }
 
   /**