diff --git a/lib/topic_query.rb b/lib/topic_query.rb
index f5c2ab12962..f52c6977469 100644
--- a/lib/topic_query.rb
+++ b/lib/topic_query.rb
@@ -346,16 +346,22 @@ class TopicQuery
   end
 
   def self.tracked_filter(list, user_id)
+    tracked_category_ids_sql = <<~SQL
+    SELECT cd.category_id FROM category_users cd
+    WHERE cd.user_id = :user_id AND cd.notification_level >= :tracking
+    SQL
+
+    has_sub_sub_categories = SiteSetting.max_category_nesting == 3
+
     sql = +<<~SQL
       topics.category_id IN (
-        SELECT cu.category_id FROM category_users cu
-        WHERE cu.user_id = :user_id AND cu.notification_level >= :tracking
-      )
-      OR topics.category_id IN (
-        SELECT c.id FROM categories c WHERE c.parent_category_id IN (
-          SELECT cd.category_id FROM category_users cd
-          WHERE cd.user_id = :user_id AND cd.notification_level >= :tracking
-        )
+        SELECT
+          c.id
+        FROM categories c
+        #{has_sub_sub_categories ? "LEFT JOIN categories parent_categories ON parent_categories.id = c.parent_category_id" : ""}
+        WHERE (c.parent_category_id IS NULL AND c.id IN (#{tracked_category_ids_sql}))
+        OR c.parent_category_id IN (#{tracked_category_ids_sql})
+        #{has_sub_sub_categories ? "OR (parent_categories.id IS NOT NULL AND parent_categories.parent_category_id IN (#{tracked_category_ids_sql}))" : ""}
       )
     SQL
 
diff --git a/spec/lib/topic_query_spec.rb b/spec/lib/topic_query_spec.rb
index ec59e77b83f..66a12cb294c 100644
--- a/spec/lib/topic_query_spec.rb
+++ b/spec/lib/topic_query_spec.rb
@@ -164,7 +164,7 @@ describe TopicQuery do
       SiteSetting.tagging_enabled = true
 
       tag = Fabricate(:tag)
-      Fabricate(:topic, tags: [tag])
+      topic = Fabricate(:topic, tags: [tag])
       topic2 = Fabricate(:topic)
 
       query = TopicQuery.new(user, filter: 'tracked').list_latest
@@ -183,26 +183,38 @@ describe TopicQuery do
       )
 
       query = TopicQuery.new(user, filter: 'tracked').list_latest
-      expect(query.topics.length).to eq(1)
+
+      expect(query.topics.map(&:id)).to contain_exactly(topic.id)
 
       cu.update!(notification_level: NotificationLevels.all[:tracking])
 
       query = TopicQuery.new(user, filter: 'tracked').list_latest
-      expect(query.topics.length).to eq(2)
+
+      expect(query.topics.map(&:id)).to contain_exactly(topic.id, topic2.id)
 
       # includes subcategories of tracked categories
-      parentcat = Fabricate(:category)
-      subcat = Fabricate(:category, parent_category_id: parentcat.id)
-      topic3 = Fabricate(:topic, category_id: subcat.id)
+      parent_category = Fabricate(:category)
+      sub_category = Fabricate(:category, parent_category_id: parent_category.id)
+      topic3 = Fabricate(:topic, category_id: sub_category.id)
 
       CategoryUser.create!(
-        category_id: parentcat.id,
+        category_id: parent_category.id,
         user_id: user.id,
         notification_level: NotificationLevels.all[:tracking]
       )
 
       query = TopicQuery.new(user, filter: 'tracked').list_latest
-      expect(query.topics.length).to eq(3)
+
+      expect(query.topics.map(&:id)).to contain_exactly(topic.id, topic2.id, topic3.id)
+
+      # includes sub-subcategories of tracked categories
+      SiteSetting.max_category_nesting = 3
+      sub_sub_category = Fabricate(:category, parent_category_id: sub_category.id)
+      topic4 = Fabricate(:topic, category_id: sub_sub_category.id)
+
+      query = TopicQuery.new(user, filter: 'tracked').list_latest
+
+      expect(query.topics.map(&:id)).to contain_exactly(topic.id, topic2.id, topic3.id, topic4.id)
     end
   end