diff --git a/app/models/observer/ticket/article_changes.rb b/app/models/observer/ticket/article_changes.rb
index a62ad9e88..c0184f6fa 100644
--- a/app/models/observer/ticket/article_changes.rb
+++ b/app/models/observer/ticket/article_changes.rb
@@ -110,6 +110,18 @@ class Observer::Ticket::ArticleChanges < ActiveRecord::Observer
     ticket = record.ticket
     if sender.name == 'Customer'
 
+      # in case, update last_contact_customer_at on any customer follow up
+      if Setting.get('ticket_last_contact_behaviour') == 'based_on_customer_reaction'
+
+        # set last_contact_at customer
+        record.ticket.last_contact_customer_at = record.created_at
+
+        # set last_contact
+        record.ticket.last_contact_at = record.created_at
+
+        return true
+      end
+
       # if customer is sending agains, ignore update of last contact (usecase of update escalation)
       return false if ticket.last_contact_customer_at &&
                       ticket.last_contact_at &&
@@ -125,7 +137,6 @@ class Observer::Ticket::ArticleChanges < ActiveRecord::Observer
 
         # set last_contact
         record.ticket.last_contact_at = record.created_at
-
       end
       return true
     end
diff --git a/db/migrate/20180521141004_ticket_last_contact_behavior.rb b/db/migrate/20180521141004_ticket_last_contact_behavior.rb
new file mode 100644
index 000000000..30d3828e7
--- /dev/null
+++ b/db/migrate/20180521141004_ticket_last_contact_behavior.rb
@@ -0,0 +1,33 @@
+class TicketLastContactBehavior < ActiveRecord::Migration[5.1]
+  def up
+    # return if it's a new setup
+    return if !Setting.find_by(name: 'system_init_done')
+
+    Setting.create_if_not_exists(
+      title: 'Ticket Last Contact Behaviour',
+      name: 'ticket_last_contact_behaviour',
+      area: 'Ticket::Base',
+      description: 'Sets the last customer contact based on the last contact of a customer or on the last contact of a customer to whom an agent has not yet responded.',
+      options: {
+        form: [
+          {
+            display: '',
+            null: true,
+            name: 'ticket_last_contact_behaviour',
+            tag: 'select',
+            translate: true,
+            options: {
+              'based_on_customer_reaction' => 'Last customer contact (without consideration an agent has replied to it)',
+              'check_if_agent_already_replied' => 'Last customer contact (with consideration an agent has replied to it)',
+            },
+          },
+        ],
+      },
+      state: 'check_if_agent_already_replied',
+      preferences: {
+        permission: ['admin.ticket'],
+      },
+      frontend: false
+    )
+  end
+end
diff --git a/db/seeds/settings.rb b/db/seeds/settings.rb
index b7275a8b1..91708b2ca 100644
--- a/db/seeds/settings.rb
+++ b/db/seeds/settings.rb
@@ -1789,6 +1789,32 @@ Setting.create_if_not_exists(
   },
   frontend: false
 )
+Setting.create_if_not_exists(
+  title: 'Ticket Last Contact Behaviour',
+  name: 'ticket_last_contact_behaviour',
+  area: 'Ticket::Base',
+  description: 'Sets the last customer contact based on the last contact of a customer or on the last contact of a customer to whom an agent has not yet responded.',
+  options: {
+    form: [
+      {
+        display: '',
+        null: true,
+        name: 'ticket_last_contact_behaviour',
+        tag: 'select',
+        translate: true,
+        options: {
+          'based_on_customer_reaction' => 'Last customer contact (without consideration an agent has replied to it)',
+          'check_if_agent_already_replied' => 'Last customer contact (with consideration an agent has replied to it)',
+        },
+      },
+    ],
+  },
+  state: 'check_if_agent_already_replied',
+  preferences: {
+    permission: ['admin.ticket'],
+  },
+  frontend: false
+)
 Setting.create_if_not_exists(
   title: 'Ticket Number Format',
   name: 'ticket_number',
diff --git a/test/unit/ticket_sla_test.rb b/test/unit/ticket_sla_test.rb
index 83f15a403..dd226aba3 100644
--- a/test/unit/ticket_sla_test.rb
+++ b/test/unit/ticket_sla_test.rb
@@ -4,11 +4,6 @@ require 'test_helper'
 class TicketSlaTest < ActiveSupport::TestCase
 
   test 'ticket sla' do
-
-    # cleanup
-    delete = Ticket.destroy_all
-    assert(delete, 'ticket destroy_all')
-
     ticket = Ticket.create!(
       title: 'some title äöüß',
       group: Group.lookup(name: 'Users'),
@@ -502,11 +497,6 @@ class TicketSlaTest < ActiveSupport::TestCase
   end
 
   test 'ticket sla + selector' do
-
-    # cleanup
-    delete = Ticket.destroy_all
-    assert(delete, 'ticket destroy_all')
-
     calendar1 = Calendar.create_or_update(
       name: 'EU 1',
       timezone: 'Europe/Berlin',
@@ -611,13 +601,6 @@ class TicketSlaTest < ActiveSupport::TestCase
   end
 
   test 'ticket sla + timezone + holiday' do
-
-    # cleanup
-    delete = Sla.destroy_all
-    assert(delete, 'sla destroy_all')
-    delete = Ticket.destroy_all
-    assert(delete, 'ticket destroy_all')
-
     ticket = Ticket.create!(
       title: 'some title äöüß',
       group: Group.lookup(name: 'Users'),
@@ -862,13 +845,6 @@ class TicketSlaTest < ActiveSupport::TestCase
   end
 
   test 'ticket escalation suspend close reopen bug' do
-
-    # cleanup
-    delete = Sla.destroy_all
-    assert(delete, 'sla destroy_all')
-    delete = Ticket.destroy_all
-    assert(delete, 'ticket destroy_all')
-
     ticket1 = Ticket.create!(
       title: 'some title äöüß3',
       group: Group.lookup(name: 'Users'),
@@ -1568,7 +1544,6 @@ class TicketSlaTest < ActiveSupport::TestCase
   end
 
   test 'ticket ticket.title and article.subject' do
-
     ticket = Ticket.create!(
       title: 'some title SLATEST1 for you',
       group: Group.lookup(name: 'Users'),
@@ -1735,13 +1710,6 @@ class TicketSlaTest < ActiveSupport::TestCase
   end
 
   test 'ticket sla + holiday 222' do
-
-    # cleanup
-    delete = Sla.destroy_all
-    assert(delete, 'sla destroy_all')
-    delete = Ticket.destroy_all
-    assert(delete, 'ticket destroy_all')
-
     ticket = Ticket.create!(
       title: 'some title 222',
       group: Group.lookup(name: 'Users'),
@@ -1961,13 +1929,6 @@ class TicketSlaTest < ActiveSupport::TestCase
   end
 
   test 'ticket sla + observer check' do
-
-    # cleanup
-    delete = Sla.destroy_all
-    assert(delete, 'sla destroy_all')
-    delete = Ticket.destroy_all
-    assert(delete, 'ticket destroy_all')
-
     ticket = Ticket.create!(
       title: 'some title observer#1',
       group: Group.lookup(name: 'Users'),
@@ -2143,4 +2104,114 @@ class TicketSlaTest < ActiveSupport::TestCase
     calendar.destroy!
   end
 
+  test 'update last_customer_contact_at when the agent does not reply' do
+
+    Setting.set('ticket_last_contact_behaviour', 'based_on_customer_reaction')
+
+    ticket = Ticket.create!(
+      title: 'test #1 last_contact_customer_at',
+      group: Group.lookup(name: 'Users'),
+      customer_id: 2,
+      state: Ticket::State.lookup(name: 'new'),
+      priority: Ticket::Priority.lookup(name: '2 normal'),
+      created_at: '2018-05-01 13:56:21 UTC',
+      updated_at: '2018-05-01 13:56:21 UTC',
+      updated_by_id: 1,
+      created_by_id: 1,
+    )
+    assert(ticket, 'ticket created')
+
+    article1 = Ticket::Article.create!(
+      ticket_id: ticket.id,
+      from: 'some_sender@example.com',
+      subject: 'some subject',
+      message_id: 'some@id',
+      body: 'some message',
+      internal: false,
+      sender: Ticket::Article::Sender.where(name: 'Customer').first,
+      type: Ticket::Article::Type.where(name: 'phone').first,
+      updated_by_id: 1,
+      created_by_id: 1,
+      created_at: '2018-05-01 13:56:21 UTC',
+      updated_at: '2018-05-01 13:56:21 UTC',
+    )
+
+    ticket.reload
+    assert_equal(ticket.article_count, 1)
+    assert_equal(ticket.last_contact_at.to_s, article1.created_at.to_s)
+    assert_equal(ticket.last_contact_customer_at.to_s, article1.created_at.to_s)
+    assert_nil(ticket.last_contact_agent_at)
+    assert_nil(ticket.first_response_at)
+    assert_nil(ticket.close_at)
+
+    article2 = Ticket::Article.create!(
+      ticket_id: ticket.id,
+      from: 'some_sender@example.com',
+      subject: 'some subject',
+      message_id: 'some@id',
+      body: 'some message',
+      internal: false,
+      sender: Ticket::Article::Sender.where(name: 'Customer').first,
+      type: Ticket::Article::Type.where(name: 'phone').first,
+      updated_by_id: 1,
+      created_by_id: 1,
+      created_at: '2018-05-01 14:56:21 UTC',
+      updated_at: '2018-05-01 14:56:21 UTC',
+    )
+
+    ticket = Ticket.find(ticket.id)
+    assert_equal(ticket.article_count, 2)
+    assert_equal(ticket.last_contact_at.to_s, article2.created_at.to_s)
+    assert_equal(ticket.last_contact_customer_at.to_s, article2.created_at.to_s)
+    assert_nil(ticket.last_contact_agent_at)
+    assert_nil(ticket.first_response_at)
+    assert_nil(ticket.close_at)
+
+    article3 = Ticket::Article.create!(
+      ticket_id: ticket.id,
+      from: 'some_sender@example.com',
+      subject: 'some subject',
+      message_id: 'some@id',
+      body: 'some message',
+      internal: false,
+      sender: Ticket::Article::Sender.where(name: 'Customer').first,
+      type: Ticket::Article::Type.where(name: 'phone').first,
+      updated_by_id: 1,
+      created_by_id: 1,
+      created_at: '2018-05-01 15:56:21 UTC',
+      updated_at: '2018-05-01 15:56:21 UTC',
+    )
+
+    ticket.reload
+    assert_equal(ticket.article_count, 3)
+    assert_equal(ticket.last_contact_at.to_s, article3.created_at.to_s)
+    assert_equal(ticket.last_contact_customer_at.to_s, article3.created_at.to_s)
+    assert_nil(ticket.last_contact_agent_at)
+    assert_nil(ticket.first_response_at)
+    assert_nil(ticket.close_at)
+
+    article4 = Ticket::Article.create!(
+      ticket_id: ticket.id,
+      from: 'some_sender@example.com',
+      subject: 'some subject',
+      message_id: 'some@id',
+      body: 'some message',
+      internal: false,
+      sender: Ticket::Article::Sender.where(name: 'Agent').first,
+      type: Ticket::Article::Type.where(name: 'phone').first,
+      updated_by_id: 1,
+      created_by_id: 1,
+      created_at: '2018-05-01 16:56:21 UTC',
+      updated_at: '2018-05-01 16:56:21 UTC',
+    )
+
+    ticket.reload
+    assert_equal(ticket.article_count, 4)
+    assert_equal(ticket.last_contact_at.to_s, article4.created_at.to_s)
+    assert_equal(ticket.last_contact_customer_at.to_s, article3.created_at.to_s)
+    assert_equal(ticket.last_contact_agent_at.to_s, article4.created_at.to_s)
+    assert_equal(ticket.first_response_at.to_s, article4.created_at.to_s)
+    assert_nil(ticket.close_at)
+  end
+
 end