diff --git a/src/notifications.js b/src/notifications.js
index bcf27c7d66..e71366417e 100644
--- a/src/notifications.js
+++ b/src/notifications.js
@@ -9,6 +9,7 @@ const _ = require('lodash');
 
 const db = require('./database');
 const User = require('./user');
+const categories = require('./categories');
 const posts = require('./posts');
 const groups = require('./groups');
 const meta = require('./meta');
@@ -84,7 +85,24 @@ Notifications.getMultiple = async function (nids) {
 	const notifications = await db.getObjects(keys);
 
 	const userKeys = notifications.map(n => n && n.from);
-	const usersData = await User.getUsersFields(userKeys, ['username', 'userslug', 'picture']);
+	let [usersData, categoriesData] = await Promise.all([
+		User.getUsersFields(userKeys, ['username', 'userslug', 'picture']),
+		categories.getCategoriesFields(userKeys, ['cid', 'name', 'slug', 'picture']),
+	]);
+	// Merge valid categoriesData into usersData
+	usersData = usersData.map((userData, idx) => {
+		const categoryData = categoriesData[idx];
+		if (!userData.uid && categoryData.cid) {
+			return {
+				username: categoryData.slug,
+				displayname: categoryData.name,
+				userslug: categoryData.slug,
+				picture: categoryData.picture,
+			};
+		}
+
+		return userData;
+	});
 
 	notifications.forEach((notification, index) => {
 		if (notification) {
diff --git a/src/socket.io/helpers.js b/src/socket.io/helpers.js
index d80638458e..5def5138d4 100644
--- a/src/socket.io/helpers.js
+++ b/src/socket.io/helpers.js
@@ -94,7 +94,10 @@ SocketHelpers.sendNotificationToPostOwner = async function (pid, fromuid, comman
 		return;
 	}
 	fromuid = utils.isNumber(fromuid) ? parseInt(fromuid, 10) : fromuid;
-	const postData = await posts.getPostFields(pid, ['tid', 'uid', 'content']);
+	const [postData, fromCategory] = await Promise.all([
+		posts.getPostFields(pid, ['tid', 'uid', 'content']),
+		!utils.isNumber(fromuid) && categories.exists(fromuid),
+	]);
 	const [canRead, isIgnoring] = await Promise.all([
 		privileges.posts.can('topics:read', pid, postData.uid),
 		topics.isIgnoring([postData.tid], postData.uid),
@@ -103,19 +106,17 @@ SocketHelpers.sendNotificationToPostOwner = async function (pid, fromuid, comman
 		return;
 	}
 	const [userData, topicTitle, postObj] = await Promise.all([
-		user.getUserFields(fromuid, ['username']),
+		fromCategory ? categories.getCategoryFields(fromuid, ['name']) : user.getUserFields(fromuid, ['username']),
 		topics.getTopicField(postData.tid, 'title'),
 		posts.parsePost(postData),
 	]);
 
-	const { displayname } = userData;
-
 	const title = utils.decodeHTMLEntities(topicTitle);
 	const titleEscaped = title.replace(/%/g, '%').replace(/,/g, ',');
 
 	const notifObj = await notifications.create({
 		type: command,
-		bodyShort: `[[${notification}, ${displayname}, ${titleEscaped}]]`,
+		bodyShort: `[[${notification}, ${userData.displayname || userData.name}, ${titleEscaped}]]`,
 		bodyLong: postObj.content,
 		pid: pid,
 		tid: postData.tid,