diff --git a/docs/configuration.md b/docs/configuration.md
index a715be3..39d4299 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -133,6 +133,15 @@ Controls how attachments in modmail threads are stored. Possible values:
 **Default:** *None*  
 When using attachmentStorage is set to "discord", the id of the channel on the inbox server where attachments are saved
 
+#### autoAlert
+**Default:** `off`  
+When enabled, the last moderator to reply to a modmail thread will be automatically alerted when the thread gets a new reply.  
+This alert kicks in after a delay, set by the `autoAlertDelay` option below.
+
+#### autoAlertDelay
+**Default:** `2m`  
+The delay after which `autoAlert` kicks in. Uses the same format as timed close; for example `1m30s` for 1 minute and 30 seconds.
+
 #### botMentionResponse
 **Default:** *None*  
 If set, the bot auto-replies to bot mentions (pings) with this message. Use `{userMention}` in the text to ping the user back.
diff --git a/src/data/Thread.js b/src/data/Thread.js
index 00e775a..ef0ecc8 100644
--- a/src/data/Thread.js
+++ b/src/data/Thread.js
@@ -169,6 +169,7 @@ class Thread {
 
   /**
    * @returns {Promise<Number>}
+   * @private
    */
   async _getAndIncrementNextMessageNumber() {
     return knex.transaction(async trx => {
@@ -186,6 +187,21 @@ class Thread {
     });
   }
 
+  /**
+   * Adds the specified moderator to the thread's alert list after config.autoAlertDelay
+   * @param {string} modId
+   * @returns {Promise<void>}
+   * @private
+   */
+  async _startAutoAlertTimer(modId) {
+    clearTimeout(this._autoAlertTimeout);
+    const autoAlertDelay = utils.convertDelayStringToMS(config.autoAlertDelay);
+    this._autoAlertTimeout = setTimeout(() => {
+      if (this.status !== THREAD_STATUS.OPEN) return;
+      this.addAlert(modId);
+    }, autoAlertDelay);
+  }
+
   /**
    * @param {Eris.Member} moderator
    * @param {string} text
@@ -296,6 +312,11 @@ class Thread {
       await this.postSystemMessage("Cancelling scheduled closing of this thread due to new reply");
     }
 
+    // If enabled, set up a reply alert for the moderator after a slight delay
+    if (config.autoAlert) {
+      this._startAutoAlertTimer(moderator.id);
+    }
+
     return true;
   }
 
diff --git a/src/data/cfg.jsdoc.js b/src/data/cfg.jsdoc.js
index 4431a30..f743562 100644
--- a/src/data/cfg.jsdoc.js
+++ b/src/data/cfg.jsdoc.js
@@ -62,6 +62,8 @@
  * @property {boolean} [errorOnUnknownInlineSnippet=true]
  * @property {boolean} [allowChangingDisplayRole=true]
  * @property {string} [fallbackRoleName=null]
+ * @property {boolean} [autoAlert=false]
+ * @property {string} [autoAlertDelay="2m"] Delay before auto-alert kicks in. Uses the same format as timed close; for example 1m30s for 1 minute and 30 seconds.
  * @property {string} [logStorage="local"]
  * @property {object} [logOptions]
  * @property {string} logOptions.attachmentDirectory
diff --git a/src/data/cfg.schema.json b/src/data/cfg.schema.json
index e490195..6d2bc30 100644
--- a/src/data/cfg.schema.json
+++ b/src/data/cfg.schema.json
@@ -346,6 +346,17 @@
       "default": null
     },
 
+    "autoAlert": {
+      "$ref": "#/definitions/customBoolean",
+      "default": false
+    },
+
+    "autoAlertDelay": {
+      "type": "string",
+      "default": "2m",
+      "description": "Delay before auto-alert kicks in. Uses the same format as timed close; for example 1m30s for 1 minute and 30 seconds."
+    },
+
     "logStorage": {
       "type": "string",
       "default": "local"
diff --git a/src/modules/reply.js b/src/modules/reply.js
index 17b5678..31ca967 100644
--- a/src/modules/reply.js
+++ b/src/modules/reply.js
@@ -1,6 +1,5 @@
 const attachments = require("../data/attachments");
 const utils = require("../utils");
-const config = require("../cfg");
 const Thread = require("../data/Thread");
 
 module.exports = ({ bot, knex, config, commands }) => {