diff --git a/app/models/user.rb b/app/models/user.rb
index 2811029705b..906955a8098 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -109,7 +109,7 @@ class User < ActiveRecord::Base
 
   has_many :sidebar_section_links, dependent: :delete_all
   has_many :category_sidebar_section_links, -> { where(linkable_type: "Category") }, class_name: 'SidebarSectionLink'
-  has_many :sidebar_tags, through: :sidebar_section_links, source: :linkable, source_type: "Tag"
+  has_many :custom_sidebar_tags, through: :sidebar_section_links, source: :linkable, source_type: "Tag"
 
   delegate :last_sent_email_address, to: :email_logs
 
@@ -1660,6 +1660,14 @@ class User < ActiveRecord::Base
     Discourse.redis.del("#{REDESIGN_USER_MENU_REDIS_KEY_PREFIX}#{self.id}")
   end
 
+  def sidebar_categories_ids
+    categories_ids = category_sidebar_section_links.pluck(:linkable_id)
+    if categories_ids.blank? && SiteSetting.default_sidebar_categories.present?
+      return guardian.allowed_category_ids & SiteSetting.default_sidebar_categories.split("|").map(&:to_i)
+    end
+    categories_ids
+  end
+
   protected
 
   def badge_grant
@@ -1952,6 +1960,15 @@ class User < ActiveRecord::Base
     end
   end
 
+  def sidebar_tags
+    return custom_sidebar_tags if custom_sidebar_tags.present?
+    if SiteSetting.default_sidebar_tags.present?
+      tag_names = SiteSetting.default_sidebar_tags.split("|") - DiscourseTagging.hidden_tag_names(guardian)
+      return Tag.where(name: tag_names)
+    end
+    []
+  end
+
   def self.ensure_consistency!
     DB.exec <<~SQL
       UPDATE users
diff --git a/app/serializers/current_user_serializer.rb b/app/serializers/current_user_serializer.rb
index cea7bda1857..e926a4b8c84 100644
--- a/app/serializers/current_user_serializer.rb
+++ b/app/serializers/current_user_serializer.rb
@@ -76,7 +76,6 @@ class CurrentUserSerializer < BasicUserSerializer
              :pending_posts_count,
              :status,
              :sidebar_category_ids,
-             :sidebar_tags,
              :likes_notifications_disabled,
              :grouped_unread_high_priority_notifications,
              :redesigned_user_menu_enabled
@@ -309,7 +308,7 @@ class CurrentUserSerializer < BasicUserSerializer
   end
 
   def sidebar_category_ids
-    object.category_sidebar_section_links.pluck(:linkable_id)
+    object.sidebar_categories_ids
   end
 
   def include_sidebar_category_ids?
diff --git a/config/locales/server.en.yml b/config/locales/server.en.yml
index 3e774e16f52..c470c0a8fe9 100644
--- a/config/locales/server.en.yml
+++ b/config/locales/server.en.yml
@@ -2380,6 +2380,8 @@ en:
     suggest_weekends_in_date_pickers: "Include weekends (Saturday and Sunday) in date picker suggestions (disable this if you use Discourse only on weekdays, Monday through Friday)."
 
     splash_screen: "Displays a temporary loading screen while site assets load"
+    default_sidebar_categories: "Selected categories will be displayed under Sidebar's Categories section by default."
+    default_sidebar_tags: "Selected tags will be displayed under Sidebar's Tags section by default."
 
     errors:
       invalid_css_color: "Invalid color. Enter a color name or hex value."
diff --git a/config/site_settings.yml b/config/site_settings.yml
index 0d1ec4f1592..22d09cdb19b 100644
--- a/config/site_settings.yml
+++ b/config/site_settings.yml
@@ -1994,6 +1994,14 @@ developer:
   enable_sidebar:
     default: true
     client: true
+  default_sidebar_categories:
+    type: category_list
+    default: ""
+    client: true
+  default_sidebar_tags:
+    type: tag_list
+    default: ""
+    client: true
 
 embedding:
   embed_by_username:
diff --git a/spec/serializers/current_user_serializer_spec.rb b/spec/serializers/current_user_serializer_spec.rb
index 85ede7e1344..7e5a79038b8 100644
--- a/spec/serializers/current_user_serializer_spec.rb
+++ b/spec/serializers/current_user_serializer_spec.rb
@@ -221,10 +221,15 @@ RSpec.describe CurrentUserSerializer do
   end
 
   describe '#sidebar_tags' do
-    fab!(:tag_sidebar_section_link) { Fabricate(:tag_sidebar_section_link, user: user) }
-    fab!(:tag_sidebar_section_link_2) { Fabricate(:tag_sidebar_section_link, user: user) }
+    fab!(:tag_1) { Fabricate(:tag, name: "foo") }
+    fab!(:tag_2) { Fabricate(:tag, name: "bar") }
+    fab!(:hidden_tag) { Fabricate(:tag, name: "secret") }
+    fab!(:staff_tag_group) { Fabricate(:tag_group, permissions: { "staff" => 1 }, tag_names: ["secret"]) }
+    let(:tag_sidebar_section_link) { Fabricate(:tag_sidebar_section_link, user: user) }
+    let(:tag_sidebar_section_link_2) { Fabricate(:tag_sidebar_section_link, user: user) }
 
     it "is not included when experimental sidebar has not been enabled" do
+      tag_sidebar_section_link
       SiteSetting.enable_experimental_sidebar_hamburger = false
       SiteSetting.tagging_enabled = true
 
@@ -234,6 +239,7 @@ RSpec.describe CurrentUserSerializer do
     end
 
     it "is not included when tagging has not been enabled" do
+      tag_sidebar_section_link
       SiteSetting.enable_experimental_sidebar_hamburger = true
       SiteSetting.tagging_enabled = false
 
@@ -243,6 +249,7 @@ RSpec.describe CurrentUserSerializer do
     end
 
     it "is present when experimental sidebar and tagging has been enabled" do
+      tag_sidebar_section_link
       SiteSetting.enable_experimental_sidebar_hamburger = true
       SiteSetting.tagging_enabled = true
 
@@ -255,13 +262,43 @@ RSpec.describe CurrentUserSerializer do
         { name: tag_sidebar_section_link_2.linkable.name, pm_only: true }
       )
     end
+
+    it 'includes visible default sidebar tags' do
+      SiteSetting.enable_experimental_sidebar_hamburger = true
+      SiteSetting.tagging_enabled = true
+      SiteSetting.default_sidebar_tags = "foo|bar|secret"
+
+      json = serializer.as_json
+
+      expect(json[:sidebar_tags]).to eq([
+        { name: "foo", pm_only: false },
+        { name: "bar", pm_only: false }
+      ])
+    end
+
+    it 'includes tags choosen by user' do
+      SiteSetting.enable_experimental_sidebar_hamburger = true
+      SiteSetting.tagging_enabled = true
+      SiteSetting.default_sidebar_tags = "foo|bar|secret"
+      tag_sidebar_section_link = Fabricate(:tag_sidebar_section_link, user: user)
+
+      json = serializer.as_json
+
+      expect(json[:sidebar_tags]).to eq([
+        { name: tag_sidebar_section_link.linkable.name, pm_only: false }
+      ])
+    end
   end
 
   describe '#sidebar_category_ids' do
-    fab!(:category_sidebar_section_link) { Fabricate(:category_sidebar_section_link, user: user) }
-    fab!(:category_sidebar_section_link_2) { Fabricate(:category_sidebar_section_link, user: user) }
+    fab!(:category) { Fabricate(:category) }
+    fab!(:category_2) { Fabricate(:category) }
+    fab!(:private_category) { Fabricate(:private_category, group: Fabricate(:group)) }
+    let(:category_sidebar_section_link) { Fabricate(:category_sidebar_section_link, user: user) }
+    let(:category_sidebar_section_link_2) { Fabricate(:category_sidebar_section_link, user: user) }
 
     it "is not included when SiteSeting.enable_experimental_sidebar_hamburger is false" do
+      category_sidebar_section_link
       SiteSetting.enable_experimental_sidebar_hamburger = false
 
       json = serializer.as_json
@@ -270,6 +307,7 @@ RSpec.describe CurrentUserSerializer do
     end
 
     it "is not included when experimental sidebar has not been enabled" do
+      category_sidebar_section_link
       SiteSetting.enable_experimental_sidebar_hamburger = false
 
       json = serializer.as_json
@@ -277,15 +315,23 @@ RSpec.describe CurrentUserSerializer do
       expect(json[:sidebar_category_ids]).to eq(nil)
     end
 
-    it "is present when experimental sidebar has been enabled" do
+    it 'includes visible default sidebar categories' do
       SiteSetting.enable_experimental_sidebar_hamburger = true
+      SiteSetting.default_sidebar_categories = "#{category.id}|#{category_2.id}|#{private_category.id}"
 
       json = serializer.as_json
+      expect(json[:sidebar_category_ids]).to eq([category.id, category_2.id])
+    end
 
-      expect(json[:sidebar_category_ids]).to contain_exactly(
-        category_sidebar_section_link.linkable_id,
-        category_sidebar_section_link_2.linkable_id
-      )
+    it 'includes categories choosen by user' do
+      SiteSetting.enable_experimental_sidebar_hamburger = true
+      SiteSetting.default_sidebar_categories = "#{category.id}|#{category_2.id}|#{private_category.id}"
+
+      category_sidebar_section_link
+      category_sidebar_section_link_2
+
+      json = serializer.as_json
+      expect(json[:sidebar_category_ids]).to eq([category_sidebar_section_link.linkable.id, category_sidebar_section_link_2.linkable.id])
     end
   end