diff --git a/db/patch-notification_sent_history.sql b/db/patch-notification_sent_history.sql
new file mode 100644
index 000000000..759eb3821
--- /dev/null
+++ b/db/patch-notification_sent_history.sql
@@ -0,0 +1,18 @@
+-- You should not modify if this have pushed to Github, unless it does serious wrong with the db.
+BEGIN TRANSACTION;
+
+CREATE TABLE [notification_sent_history] (
+    [id] INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
+    [type] VARCHAR(50) NOT NULL,
+    [monitor_id] INTEGER NOT NULL,
+    [days] INTEGER NOT NULL,
+    UNIQUE([type], [monitor_id], [days])
+);
+
+CREATE INDEX [good_index] ON [notification_sent_history] (
+    [type],
+    [monitor_id],
+    [days]
+);
+
+COMMIT;
diff --git a/server/database.js b/server/database.js
index 98494251d..41d91e858 100644
--- a/server/database.js
+++ b/server/database.js
@@ -51,6 +51,7 @@ class Database {
         "patch-monitor-push_token.sql": true,
         "patch-http-monitor-method-body-and-headers.sql": true,
         "patch-2fa-invalidate-used-token.sql": true,
+        "patch-notification_sent_history.sql": true,
     }
 
     /**
diff --git a/server/jobs.js b/server/jobs.js
index 8a768b91b..0469d5cab 100644
--- a/server/jobs.js
+++ b/server/jobs.js
@@ -6,7 +6,7 @@ const jobs = [
     {
         name: "clear-old-data",
         interval: "at 03:14",
-    }
+    },
 ];
 
 const initBackgroundJobs = function (args) {
diff --git a/server/model/monitor.js b/server/model/monitor.js
index 2f28e5b95..a1aa1656d 100644
--- a/server/model/monitor.js
+++ b/server/model/monitor.js
@@ -168,7 +168,14 @@ class Monitor extends BeanModel {
                     let certInfoStartTime = dayjs().valueOf();
                     if (this.getUrl()?.protocol === "https:") {
                         try {
-                            tlsInfo = await this.updateTlsInfo(checkCertificate(res));
+                            let tlsInfoObject = checkCertificate(res);
+                            tlsInfo = await this.updateTlsInfo(tlsInfoObject);
+
+                            if (!this.getIgnoreTls()) {
+                                debug("call sendCertNotification");
+                                await this.sendCertNotification(tlsInfoObject);
+                            }
+
                         } catch (e) {
                             if (e.message !== "No TLS certificate in response") {
                                 console.error(e.message);
@@ -444,10 +451,36 @@ class Monitor extends BeanModel {
         let tls_info_bean = await R.findOne("monitor_tls_info", "monitor_id = ?", [
             this.id,
         ]);
+
         if (tls_info_bean == null) {
             tls_info_bean = R.dispense("monitor_tls_info");
             tls_info_bean.monitor_id = this.id;
+        } else {
+
+            // Clear sent history if the cert changed.
+            try {
+                let oldCertInfo = JSON.parse(tls_info_bean.info_json);
+
+                let isValidObjects = oldCertInfo && oldCertInfo.certInfo && checkCertificateResult && checkCertificateResult.certInfo;
+
+                if (isValidObjects) {
+                    if (oldCertInfo.certInfo.fingerprint256 !== checkCertificateResult.certInfo.fingerprint256) {
+                        debug("Resetting sent_history");
+                        await R.exec("DELETE FROM notification_sent_history WHERE type = 'certificate' AND monitor_id = ?", [
+                            this.id
+                        ]);
+                    } else {
+                        debug("No need to reset sent_history");
+                        debug(oldCertInfo.certInfo.fingerprint256);
+                        debug(checkCertificateResult.certInfo.fingerprint256);
+                    }
+                } else {
+                    debug("Not valid object");
+                }
+            } catch (e) { }
+
         }
+
         tls_info_bean.info_json = JSON.stringify(checkCertificateResult);
         await R.store(tls_info_bean);
 
@@ -595,9 +628,7 @@ class Monitor extends BeanModel {
 
     static async sendNotification(isFirstBeat, monitor, bean) {
         if (!isFirstBeat || bean.status === DOWN) {
-            let notificationList = await R.getAll("SELECT notification.* FROM notification, monitor_notification WHERE monitor_id = ? AND monitor_notification.notification_id = notification.id ", [
-                monitor.id,
-            ]);
+            const notificationList = await Monitor.getNotificationList(monitor);
 
             let text;
             if (bean.status === UP) {
@@ -619,6 +650,70 @@ class Monitor extends BeanModel {
         }
     }
 
+    static async getNotificationList(monitor) {
+        let notificationList = await R.getAll("SELECT notification.* FROM notification, monitor_notification WHERE monitor_id = ? AND monitor_notification.notification_id = notification.id ", [
+            monitor.id,
+        ]);
+        return notificationList;
+    }
+
+    async sendCertNotification(tlsInfoObject) {
+        if (tlsInfoObject && tlsInfoObject.certInfo && tlsInfoObject.certInfo.daysRemaining) {
+            const notificationList = await Monitor.getNotificationList(this);
+
+            debug("call sendCertNotificationByTargetDays");
+            await this.sendCertNotificationByTargetDays(tlsInfoObject.certInfo.daysRemaining, 21, notificationList);
+            await this.sendCertNotificationByTargetDays(tlsInfoObject.certInfo.daysRemaining, 14, notificationList);
+            await this.sendCertNotificationByTargetDays(tlsInfoObject.certInfo.daysRemaining, 7, notificationList);
+        }
+    }
+
+    async sendCertNotificationByTargetDays(daysRemaining, targetDays, notificationList) {
+
+        if (daysRemaining > targetDays) {
+            debug(`No need to send cert notification. ${daysRemaining} > ${targetDays}`);
+            return;
+        }
+
+        if (notificationList.length > 0) {
+
+            let row = await R.getRow("SELECT * FROM notification_sent_history WHERE type = ? AND monitor_id = ? AND days = ?", [
+                "certificate",
+                this.id,
+                targetDays,
+            ]);
+
+            // Sent already, no need to send again
+            if (row) {
+                debug("Sent already, no need to send again");
+                return;
+            }
+
+            let sent = false;
+            debug("Send certificate notification");
+
+            for (let notification of notificationList) {
+                try {
+                    debug("Sending to " + notification.name);
+                    await Notification.send(JSON.parse(notification.config), `[${this.name}][${this.url}] Certificate will be expired in ${daysRemaining} days`);
+                    sent = true;
+                } catch (e) {
+                    console.error("Cannot send cert notification to " + notification.name);
+                    console.error(e);
+                }
+            }
+
+            if (sent) {
+                await R.exec("INSERT INTO notification_sent_history (type, monitor_id, days) VALUES(?, ?, ?)", [
+                    "certificate",
+                    this.id,
+                    targetDays,
+                ]);
+            }
+        } else {
+            debug("No notification, no need to send cert notification");
+        }
+    }
 }
 
 module.exports = Monitor;