diff --git a/quickshell/Services/NotificationService.qml b/quickshell/Services/NotificationService.qml
index 0294f3f2..0615b580 100644
--- a/quickshell/Services/NotificationService.qml
+++ b/quickshell/Services/NotificationService.qml
@@ -19,6 +19,7 @@ Singleton {
     readonly property string historyFile: Paths.strip(Paths.cache) + "/notification_history.json"
     readonly property string imageCacheDir: Paths.strip(Paths.cache) + "/notification_images"
     property bool historyLoaded: false
+    property int historyEntryCounter: 0
 
     property list<NotifWrapper> notificationQueue: []
     property list<NotifWrapper> visibleNotifications: []
@@ -73,6 +74,12 @@ Singleton {
         onTriggered: root.performSaveHistory()
     }
 
+    function _makeHistoryEntryId(sourceId, timestamp) {
+        historyEntryCounter += 1;
+        const safeSource = sourceId && sourceId !== "" ? sourceId : "notification";
+        return safeSource + "_" + (timestamp || Date.now()) + "_" + historyEntryCounter;
+    }
+
     function getImageCachePath(wrapper) {
         const ts = wrapper.time ? wrapper.time.getTime() : Date.now();
         const id = wrapper.notification?.id?.toString() || "0";
@@ -80,12 +87,13 @@ Singleton {
     }
 
     function updateHistoryImage(wrapperId, imagePath) {
-        const idx = historyList.findIndex(n => n.id === wrapperId);
+        const idx = historyList.findIndex(n => n.sourceNotificationId === wrapperId || n.id === wrapperId);
         if (idx < 0)
             return;
         const item = historyList[idx];
         const updated = {
             id: item.id,
+            sourceNotificationId: item.sourceNotificationId || item.id,
             summary: item.summary,
             body: item.body,
             htmlBody: item.htmlBody,
@@ -113,8 +121,11 @@ Singleton {
         } else if (imageUrl && !imageUrl.startsWith("image://qsimage/")) {
             persistableImage = imageUrl;
         }
+        const sourceNotificationId = wrapper.notification?.id?.toString() || "";
+        const timestamp = wrapper.time.getTime();
         const data = {
-            id: wrapper.notification?.id?.toString() || Date.now().toString(),
+            id: _makeHistoryEntryId(sourceNotificationId, timestamp),
+            sourceNotificationId: sourceNotificationId,
             summary: wrapper.summary || "",
             body: wrapper.body || "",
             htmlBody: wrapper.htmlBody || wrapper.body || "",
@@ -122,7 +133,7 @@ Singleton {
             appIcon: wrapper.appIcon || "",
             image: persistableImage,
             urgency: urg,
-            timestamp: wrapper.time.getTime(),
+            timestamp: timestamp,
             desktopEntry: wrapper.desktopEntry || ""
         };
         let newList = [data, ...historyList];
@@ -152,6 +163,8 @@ Singleton {
             const now = Date.now();
             const maxAgeMs = maxAgeDays > 0 ? maxAgeDays * 24 * 60 * 60 * 1000 : 0;
             const loaded = [];
+            const seenIds = {};
+            let needsRewrite = false;
 
             for (const item of historyAdapter.notifications || []) {
                 if (maxAgeMs > 0 && (now - item.timestamp) > maxAgeMs)
@@ -162,8 +175,18 @@ Singleton {
                 if (htmlBody) {
                     htmlBody = htmlBody.replace(/<img\b[^>]*>/gi, "");
                 }
+                const sourceNotificationId = (item.sourceNotificationId || item.id || "").toString();
+                let historyId = (item.id || "").toString();
+                if (!historyId || seenIds[historyId]) {
+                    historyId = _makeHistoryEntryId(sourceNotificationId, item.timestamp || now);
+                    needsRewrite = true;
+                }
+                if (!item.sourceNotificationId)
+                    needsRewrite = true;
+                seenIds[historyId] = true;
                 loaded.push({
-                    id: item.id || "",
+                    id: historyId,
+                    sourceNotificationId: sourceNotificationId,
                     summary: item.summary || "",
                     body: body,
                     htmlBody: htmlBody,
@@ -177,7 +200,7 @@ Singleton {
             }
             historyList = loaded;
             historyLoaded = true;
-            if (maxAgeMs > 0 && loaded.length !== (historyAdapter.notifications || []).length)
+            if ((maxAgeMs > 0 && loaded.length !== (historyAdapter.notifications || []).length) || needsRewrite)
                 saveHistory();
         } catch (e) {
             console.warn("NotificationService: load history failed:", e);