diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index ff085e6dc..ae9e1beb9 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -3,8 +3,17 @@ class ApplicationController < ActionController::Base
 
   rescue_from Pundit::NotAuthorizedError, with: :render_not_authorized
 
+  before_action :check_maintenance
   before_action :set_paper_trail_whodunnit
 
+  def check_maintenance
+    if FeatureToggle.maintenance_mode_enabled? && !%w[service-unavailable accessibility-statement privacy-notice cookies].include?(request.fullpath.split("?")[0].delete("/"))
+      redirect_to service_unavailable_path
+    elsif !FeatureToggle.maintenance_mode_enabled? && request.fullpath.split("?")[0].delete("/") == "service-unavailable"
+      redirect_back(fallback_location: root_path)
+    end
+  end
+
   def render_not_found
     render "errors/not_found", status: :not_found
   end
diff --git a/app/controllers/maintenance_controller.rb b/app/controllers/maintenance_controller.rb
new file mode 100644
index 000000000..bb6ae1f80
--- /dev/null
+++ b/app/controllers/maintenance_controller.rb
@@ -0,0 +1,7 @@
+class MaintenanceController < ApplicationController
+  def service_unavailable
+    if current_user
+      sign_out
+    end
+  end
+end
diff --git a/app/services/feature_toggle.rb b/app/services/feature_toggle.rb
index 379f51905..3cad5dadb 100644
--- a/app/services/feature_toggle.rb
+++ b/app/services/feature_toggle.rb
@@ -37,4 +37,8 @@ class FeatureToggle
   def self.duplicate_summary_enabled?
     !Rails.env.production?
   end
+
+  def self.maintenance_mode_enabled?
+    false
+  end
 end
diff --git a/app/views/layouts/application.html.erb b/app/views/layouts/application.html.erb
index ead90793a..d70c1e09a 100644
--- a/app/views/layouts/application.html.erb
+++ b/app/views/layouts/application.html.erb
@@ -91,11 +91,13 @@
       navigation_classes: "govuk-header__navigation--end",
     ) do |component|
       component.product_name(name: t("service_name"))
-      if current_user.nil?
-        component.navigation_item(text: "Sign in", href: user_session_path)
-      else
-        component.navigation_item(text: "Your account", href: account_path)
-        component.navigation_item(text: "Sign out", href: destroy_user_session_path)
+      unless FeatureToggle.maintenance_mode_enabled?
+        if current_user.nil?
+          component.navigation_item(text: "Sign in", href: user_session_path)
+        else
+          component.navigation_item(text: "Your account", href: account_path)
+          component.navigation_item(text: "Sign out", href: destroy_user_session_path)
+        end
       end
     end %>
 
diff --git a/app/views/maintenance/service_unavailable.html.erb b/app/views/maintenance/service_unavailable.html.erb
new file mode 100644
index 000000000..cb106ce8d
--- /dev/null
+++ b/app/views/maintenance/service_unavailable.html.erb
@@ -0,0 +1,11 @@
+<h1 class="govuk-heading-l govuk-!-width-two-thirds">
+  Sorry, the service is unavailable
+</h1>
+
+<div class="govuk-grid-row">
+  <div class="govuk-grid-column-two-thirds-from-desktop">
+    <p class="govuk-body">You will be able to use the service from 9am on Thursday 16 November 2023.</p>
+    <p class="govuk-body">Changes from the page you were on have not been saved. Changes on pages where you have selected 'save and continue' have been saved.</p>
+    <p class="govuk-body"><%= govuk_link_to "Contact the helpdesk", "https://dluhcdigital.atlassian.net/servicedesk/customer/portal/6/group/11" %> if you need help.</p>
+  </div>
+</div>
diff --git a/config/initializers/sidekiq.rb b/config/initializers/sidekiq.rb
index 74e6ce9a2..60cc29b3a 100644
--- a/config/initializers/sidekiq.rb
+++ b/config/initializers/sidekiq.rb
@@ -32,7 +32,10 @@ Redis.silence_deprecations = true
 
 Sidekiq.configure_server do |config|
   config.on(:startup) do
-    Sidekiq::Cron::Job.load_from_hash YAML.load_file("config/sidekiq_cron_schedule.yml")
+    Sidekiq::Cron::Job.all.each(&:destroy)
+    unless FeatureToggle.maintenance_mode_enabled?
+      Sidekiq::Cron::Job.load_from_hash YAML.load_file("config/sidekiq_cron_schedule.yml")
+    end
   end
 
   config.on(:shutdown) do
diff --git a/config/routes.rb b/config/routes.rb
index 621ee820c..498e7d9a2 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -35,6 +35,7 @@ Rails.application.routes.draw do
   get "/accessibility-statement", to: "content#accessibility_statement"
   get "/privacy-notice", to: "content#privacy_notice"
   get "/data-sharing-agreement", to: "content#data_sharing_agreement"
+  get "/service-unavailable", to: "maintenance#service_unavailable"
 
   get "/download-23-24-lettings-form", to: "start#download_23_24_lettings_form"
   get "/download-22-23-lettings-form", to: "start#download_22_23_lettings_form"
diff --git a/spec/controllers/maintenance_controller_spec.rb b/spec/controllers/maintenance_controller_spec.rb
new file mode 100644
index 000000000..032ac4858
--- /dev/null
+++ b/spec/controllers/maintenance_controller_spec.rb
@@ -0,0 +1,27 @@
+require "rails_helper"
+
+RSpec.describe MaintenanceController do
+  let(:user) { FactoryBot.create(:user) }
+
+  describe "GET #service_unavailable" do
+    context "when maintenance mode is enabled" do
+      it "logs the user out" do
+        allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(true)
+        sign_in user
+        expect(controller).to be_user_signed_in
+        get :service_unavailable
+        expect(controller).not_to be_user_signed_in
+      end
+    end
+
+    context "when maintenance mode is disabled" do
+      it "doesn't log the user out" do
+        allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(false)
+        sign_in user
+        expect(controller).to be_user_signed_in
+        get :service_unavailable
+        expect(controller).to be_user_signed_in
+      end
+    end
+  end
+end
diff --git a/spec/features/user_spec.rb b/spec/features/user_spec.rb
index 39327a75a..ca4e01ac6 100644
--- a/spec/features/user_spec.rb
+++ b/spec/features/user_spec.rb
@@ -139,6 +139,12 @@ RSpec.describe "User Features" do
       visit("/users/#{user.id}")
       expect(page).to have_content("Sign in to your account to submit CORE data")
     end
+
+    it "does not show 'Sign in' link if maintenance mode is enabled" do
+      allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(true)
+      visit("/lettings-logs")
+      expect(page).not_to have_link("Sign in")
+    end
   end
 
   context "when the user is trying to log in with incorrect credentials" do
@@ -324,6 +330,13 @@ RSpec.describe "User Features" do
         expect(page).to have_selector('[data-qa="change-data-protection-officer"]')
         expect(page).to have_selector('[data-qa="change-key-contact"]')
       end
+
+      it "does not show 'Your account' or 'Sign out' links if maintenance mode is enabled" do
+        allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(true)
+        visit("/lettings-logs")
+        expect(page).not_to have_link("Your account")
+        expect(page).not_to have_link("Sign out")
+      end
     end
 
     context "when adding a new user" do
diff --git a/spec/requests/content_controller_spec.rb b/spec/requests/content_controller_spec.rb
index 07be4256b..c978ecaa9 100644
--- a/spec/requests/content_controller_spec.rb
+++ b/spec/requests/content_controller_spec.rb
@@ -4,45 +4,81 @@ RSpec.describe ContentController, type: :request do
   let(:headers) { { "Accept" => "text/html" } }
   let(:page) { Capybara::Node::Simple.new(response.body) }
 
-  describe "render privacy notice content page" do
-    before do
-      get "/privacy-notice", headers:, params: {}
-    end
+  describe "when maintenance mode is disabled" do
+    describe "render privacy notice content page" do
+      before do
+        get "/privacy-notice", headers:, params: {}
+      end
 
-    it "returns a 200" do
-      expect(response).to have_http_status(:success)
-    end
+      it "returns a 200" do
+        expect(response).to have_http_status(:success)
+      end
 
-    it "returns the page" do
-      expect(page).to have_title("Privacy notice")
+      it "returns the page" do
+        expect(page).to have_title("Privacy notice")
+      end
     end
-  end
 
-  describe "render accessibility statement content page" do
-    before do
-      get "/accessibility-statement", headers:, params: {}
-    end
+    describe "render accessibility statement content page" do
+      before do
+        get "/accessibility-statement", headers:, params: {}
+      end
+
+      it "returns a 200" do
+        expect(response).to have_http_status(:success)
+      end
 
-    it "returns a 200" do
-      expect(response).to have_http_status(:success)
+      it "returns the page" do
+        expect(page).to have_title("Accessibility statement")
+      end
     end
 
-    it "returns the page" do
-      expect(page).to have_title("Accessibility statement")
+    describe "render data sharing agreement" do
+      before do
+        get "/data-sharing-agreement", headers:, params: {}
+      end
+
+      it "returns a 200" do
+        expect(response).to have_http_status(:success)
+      end
+
+      it "returns the page" do
+        expect(page).to have_title("Data sharing agreement")
+      end
     end
   end
 
-  describe "render data sharing agreement" do
+  describe "when maintenance mode is enabled" do
     before do
-      get "/data-sharing-agreement", headers:, params: {}
+      allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(true)
     end
 
-    it "returns a 200" do
-      expect(response).to have_http_status(:success)
+    describe "render privacy notice content page" do
+      before do
+        get "/privacy-notice", headers:, params: {}
+      end
+
+      it "returns a 200" do
+        expect(response).to have_http_status(:success)
+      end
+
+      it "returns the page" do
+        expect(page).to have_title("Privacy notice")
+      end
     end
 
-    it "returns the page" do
-      expect(page).to have_title("Data sharing agreement")
+    describe "render accessibility statement content page" do
+      before do
+        get "/accessibility-statement", headers:, params: {}
+      end
+
+      it "returns a 200" do
+        expect(response).to have_http_status(:success)
+      end
+
+      it "returns the page" do
+        expect(page).to have_title("Accessibility statement")
+      end
     end
   end
 end
diff --git a/spec/requests/cookies_controller_spec.rb b/spec/requests/cookies_controller_spec.rb
new file mode 100644
index 000000000..82cf06a10
--- /dev/null
+++ b/spec/requests/cookies_controller_spec.rb
@@ -0,0 +1,42 @@
+require "rails_helper"
+
+RSpec.describe CookiesController, type: :request do
+  let(:headers) { { "Accept" => "text/html" } }
+  let(:page) { Capybara::Node::Simple.new(response.body) }
+
+  describe "when maintenance mode is disabled" do
+    describe "render cookies page" do
+      before do
+        get "/cookies", headers:, params: {}
+      end
+
+      it "returns a 200" do
+        expect(response).to have_http_status(:success)
+      end
+
+      it "returns the page" do
+        expect(page).to have_title("Cookies")
+      end
+    end
+  end
+
+  describe "when maintenance mode is enabled" do
+    before do
+      allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(true)
+    end
+
+    describe "render cookies page" do
+      before do
+        get "/cookies", headers:, params: {}
+      end
+
+      it "returns a 200" do
+        expect(response).to have_http_status(:success)
+      end
+
+      it "returns the page" do
+        expect(page).to have_title("Cookies")
+      end
+    end
+  end
+end
diff --git a/spec/requests/maintenance_controller_spec.rb b/spec/requests/maintenance_controller_spec.rb
new file mode 100644
index 000000000..d900df3c5
--- /dev/null
+++ b/spec/requests/maintenance_controller_spec.rb
@@ -0,0 +1,85 @@
+require "rails_helper"
+
+RSpec.describe MaintenanceController, type: :request do
+  let(:page) { Capybara::Node::Simple.new(response.body) }
+  let(:user) { FactoryBot.create(:user) }
+
+  before do
+    sign_in user
+  end
+
+  describe "when maintenance mode is enabled" do
+    before do
+      allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(true)
+    end
+
+    context "when a user visits a page other than the maintenance page" do
+      before do
+        get "/lettings-logs"
+      end
+
+      it "redirects the user to the maintenance page" do
+        expect(response).to redirect_to(service_unavailable_path)
+        follow_redirect!
+        expect(page).to have_content("Sorry, the service is unavailable")
+      end
+
+      it "the cookie banner is visible" do
+        follow_redirect!
+        expect(page).to have_content("We’d like to use analytics cookies so we can understand how you use the service and make improvements.")
+      end
+    end
+
+    context "when a user visits the maintenance page" do
+      before do
+        get "/service-unavailable"
+      end
+
+      it "keeps the user on the maintenance page" do
+        expect(response).not_to redirect_to(service_unavailable_path)
+        expect(page).to have_content("Sorry, the service is unavailable")
+      end
+
+      it "the cookie banner is visible" do
+        expect(page).to have_content("We’d like to use analytics cookies so we can understand how you use the service and make improvements.")
+      end
+    end
+  end
+
+  describe "when maintenance mode is disabled" do
+    before do
+      allow(FeatureToggle).to receive(:maintenance_mode_enabled?).and_return(false)
+    end
+
+    context "when a user visits a page other than the maintenance page" do
+      before do
+        get "/lettings-logs"
+      end
+
+      it "doesn't redirect the user to the maintenance page" do
+        expect(response).not_to redirect_to(service_unavailable_path)
+        expect(page).to have_content("Create a new lettings log")
+      end
+
+      it "the cookie banner is visible" do
+        expect(page).to have_content("We’d like to use analytics cookies so we can understand how you use the service and make improvements.")
+      end
+    end
+
+    context "when a user visits the maintenance page" do
+      before do
+        get "/service-unavailable"
+      end
+
+      it "redirects the user to the start page" do
+        expect(response).to redirect_to(root_path)
+      end
+
+      it "the cookie banner is visible" do
+        follow_redirect!
+        follow_redirect!
+        expect(page).to have_content("We’d like to use analytics cookies so we can understand how you use the service and make improvements.")
+      end
+    end
+  end
+end