diff --git a/pos/static/js/dashboard.js b/pos/static/js/dashboard.js
index f5e8205..96c8591 100644
--- a/pos/static/js/dashboard.js
+++ b/pos/static/js/dashboard.js
@@ -495,16 +495,15 @@ const Dashboard = (() => {
                 buckets[label] = { total: 0, date: d };
             });
         } else if (period === 'mes') {
-            const start = new Date();
-            start.setDate(start.getDate() - 27);
-            dateFrom = start.toISOString().slice(0, 10);
-            dateTo = todayStr();
-            for (let i = 3; i >= 0; i--) {
-                const d = new Date();
-                d.setDate(d.getDate() - (i * 7 + 6));
-                const label = weekLabel(d);
+            const year = now.getFullYear();
+            const month = now.getMonth();
+            const lastDay = new Date(year, month + 1, 0).getDate();
+            dateFrom = new Date(year, month, 1).toISOString().slice(0, 10);
+            dateTo = new Date(year, month, lastDay).toISOString().slice(0, 10);
+            for (let i = 1; i <= 4; i++) {
+                const label = `Sem ${i}`;
                 labelOrder.push(label);
-                buckets[label] = 0;
+                buckets[label] = { total: 0, week: i };
             }
         } else if (period === 'año') {
             for (let i = 11; i >= 0; i--) {
@@ -558,17 +557,9 @@ const Dashboard = (() => {
             if (period === 'hoy') key = 'Hoy';
             else if (period === 'semana') key = DAY_NAMES_SHORT[date.getDay()];
             else if (period === 'mes') {
-                // Find which week bucket this date belongs to
-                for (let i = 0; i < 4; i++) {
-                    const bucketStart = new Date();
-                    bucketStart.setDate(bucketStart.getDate() - ((3 - i) * 7 + 6));
-                    const bucketEnd = new Date(bucketStart);
-                    bucketEnd.setDate(bucketEnd.getDate() + 6);
-                    if (date >= bucketStart && date <= bucketEnd) {
-                        key = labelOrder[i];
-                        break;
-                    }
-                }
+                const day = date.getDate();
+                const weekNum = day <= 7 ? 1 : day <= 14 ? 2 : day <= 21 ? 3 : 4;
+                key = `Sem ${weekNum}`;
             } else {
                 key = monthLabel(date);
             }
diff --git a/pos/templates/dashboard.html b/pos/templates/dashboard.html
index 66183e0..2ad7b7d 100644
--- a/pos/templates/dashboard.html
+++ b/pos/templates/dashboard.html
@@ -568,7 +568,7 @@
   <script src="/pos/static/js/pos-utils.js?v=2" defer></script>
   <script src="/pos/static/js/sidebar.js" defer></script>
   <script src="/pos/static/js/dashboard-stats.js?v=3" defer></script>
-  <script src="/pos/static/js/dashboard.js?v=6" defer></script>
+  <script src="/pos/static/js/dashboard.js?v=7" defer></script>
   <script src="/pos/static/js/sync-engine.js" defer></script>
   <script>if('serviceWorker' in navigator){navigator.serviceWorker.register('/pos/sw.js',{scope:'/pos/'});}</script>
   <script src="/pos/static/js/pwa-install.js" defer></script>