diff --git a/app/controllers/admin/backups_controller.rb b/app/controllers/admin/backups_controller.rb
index 2c71943b488..feed2a709d1 100644
--- a/app/controllers/admin/backups_controller.rb
+++ b/app/controllers/admin/backups_controller.rb
@@ -103,6 +103,8 @@ class Admin::BackupsController < Admin::AdminController
       Discourse.disable_readonly_mode(readonly_mode_key)
     end
 
+    StaffActionLogger.new(current_user).log_change_readonly_mode(enable)
+
     render nothing: true
   end
 
diff --git a/app/models/user_history.rb b/app/models/user_history.rb
index e7db96a5f64..ddc48286630 100644
--- a/app/models/user_history.rb
+++ b/app/models/user_history.rb
@@ -58,7 +58,8 @@ class UserHistory < ActiveRecord::Base
                           wizard_step: 40,
                           lock_trust_level: 41,
                           unlock_trust_level: 42,
-                          activate_user: 43
+                          activate_user: 43,
+                          change_readonly_mode: 44
                          )
   end
 
@@ -97,7 +98,8 @@ class UserHistory < ActiveRecord::Base
                         :deactivate_user,
                         :lock_trust_level,
                         :unlock_trust_level,
-                        :activate_user]
+                        :activate_user,
+                        :change_readonly_mode]
   end
 
   def self.staff_action_ids
diff --git a/app/services/staff_action_logger.rb b/app/services/staff_action_logger.rb
index 9efe294e989..c872fdd0f6b 100644
--- a/app/services/staff_action_logger.rb
+++ b/app/services/staff_action_logger.rb
@@ -373,11 +373,18 @@ class StaffActionLogger
     raise Discourse::InvalidParameters.new(:step) unless step
     UserHistory.create(params(opts).merge({
       action: UserHistory.actions[:wizard_step],
-      acting_user_id: @admin.id,
       context: step.id
     }))
   end
 
+  def log_change_readonly_mode(state)
+    UserHistory.create(params.merge({
+      action: UserHistory.actions[:change_readonly_mode],
+      previous_value: !state,
+      new_value: state
+    }))
+  end
+
   private
 
     def params(opts=nil)
diff --git a/config/locales/client.en.yml b/config/locales/client.en.yml
index bbe0aab2c83..0620de21f37 100644
--- a/config/locales/client.en.yml
+++ b/config/locales/client.en.yml
@@ -2919,6 +2919,7 @@ en:
             unlock_trust_level: "unlock trust level"
             activate_user: "activate user"
             deactivate_user: "deactivate user"
+            change_readonly_mode: "change readonly mode"
         screened_emails:
           title: "Screened Emails"
           description: "When someone tries to create a new account, the following email addresses will be checked and the registration will be blocked, or some other action performed."
diff --git a/spec/controllers/admin/backups_controller_spec.rb b/spec/controllers/admin/backups_controller_spec.rb
index 080f4eb6c35..270dc9a2317 100644
--- a/spec/controllers/admin/backups_controller_spec.rb
+++ b/spec/controllers/admin/backups_controller_spec.rb
@@ -179,17 +179,29 @@ describe Admin::BackupsController do
       it "enables readonly mode" do
         Discourse.expects(:enable_readonly_mode)
 
-        xhr :put, :readonly, enable: true
+        expect { xhr :put, :readonly, enable: true }
+          .to change { UserHistory.count }.by(1)
 
         expect(response).to be_success
+
+        user_history = UserHistory.last
+
+        expect(UserHistory.last.action).to eq(UserHistory.actions[:change_readonly_mode])
+        expect(UserHistory.last.new_value).to eq('t')
       end
 
       it "disables readonly mode" do
         Discourse.expects(:disable_readonly_mode)
 
-        xhr :put, :readonly, enable: false
+        expect { xhr :put, :readonly, enable: false }
+          .to change { UserHistory.count }.by(1)
 
         expect(response).to be_success
+
+        user_history = UserHistory.last
+
+        expect(UserHistory.last.action).to eq(UserHistory.actions[:change_readonly_mode])
+        expect(UserHistory.last.new_value).to eq('f')
       end
 
     end
diff --git a/spec/services/staff_action_logger_spec.rb b/spec/services/staff_action_logger_spec.rb
index 773f990d104..df2e4c6a9ca 100644
--- a/spec/services/staff_action_logger_spec.rb
+++ b/spec/services/staff_action_logger_spec.rb
@@ -370,6 +370,7 @@ describe StaffActionLogger do
     end
   end
 
+<<<<<<< 240c4870cfa43dea222ed52d4ce57b6ac186588d
   describe 'log_lock_trust_level' do
     let(:user) { Fabricate(:user) }
 
@@ -405,6 +406,25 @@ describe StaffActionLogger do
       user_history = UserHistory.last
       expect(user_history.action).to eq(UserHistory.actions[:activate_user])
       expect(user_history.details).to eq(reason)
+  end
+
+  describe '#log_readonly_mode' do
+    it "creates a new record" do
+      expect { logger.log_change_readonly_mode(true) }.to change { UserHistory.count }.by(1)
+
+      user_history = UserHistory.last
+
+      expect(user_history.action).to eq(UserHistory.actions[:change_readonly_mode])
+      expect(user_history.new_value).to eq('t')
+      expect(user_history.previous_value).to eq('f')
+
+      expect { logger.log_change_readonly_mode(false) }.to change { UserHistory.count }.by(1)
+
+      user_history = UserHistory.last
+
+      expect(user_history.action).to eq(UserHistory.actions[:change_readonly_mode])
+      expect(user_history.new_value).to eq('f')
+      expect(user_history.previous_value).to eq('t')
     end
   end
 end