diff --git a/app/models/post.rb b/app/models/post.rb
index 1b1766115..aa1e03f79 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -440,6 +440,11 @@ class Post < ActiveRecord::Base
     )
 
     revise(actor, { raw: self.raw, user_id: new_user.id, edit_reason: edit_reason })
+
+    if post_number == topic.highest_post_number
+      topic.update_columns(last_post_user_id: new_user.id)
+    end
+
   end
 
   before_create do
diff --git a/spec/services/post_owner_changer_spec.rb b/spec/services/post_owner_changer_spec.rb
index 7cd734829..6328fac29 100644
--- a/spec/services/post_owner_changer_spec.rb
+++ b/spec/services/post_owner_changer_spec.rb
@@ -21,8 +21,9 @@ describe PostOwnerChanger do
 
     it "changes the user" do
       old_user = p1.user
-      described_class.new(post_ids: [p1.id], topic_id: topic.id, new_owner: user_a, acting_user: editor).change_owner!
+      PostOwnerChanger.new(post_ids: [p1.id], topic_id: topic.id, new_owner: user_a, acting_user: editor).change_owner!
       p1.reload
+      expect(p1.topic.last_post_user_id).to eq(user_a.id)
       expect(old_user).not_to eq(p1.user)
       expect(p1.user).to eq(user_a)
     end