diff --git a/app/controllers/invites_controller.rb b/app/controllers/invites_controller.rb
index acd5b49f4f..5d84267d84 100644
--- a/app/controllers/invites_controller.rb
+++ b/app/controllers/invites_controller.rb
@@ -12,7 +12,7 @@ class InvitesController < ApplicationController
 
   before_action :ensure_invites_allowed, only: [:show, :perform_accept_invitation]
   before_action :ensure_new_registrations_allowed, only: [:show, :perform_accept_invitation]
-  before_action :ensure_not_logged_in, only: [:show, :perform_accept_invitation]
+  before_action :ensure_not_logged_in, only: :perform_accept_invitation
 
   def show
     expires_now
@@ -21,6 +21,32 @@ class InvitesController < ApplicationController
 
     invite = Invite.find_by(invite_key: params[:id])
     if invite.present? && invite.redeemable?
+      if current_user
+        added_to_group = false
+
+        if invite.groups.present?
+          invite_by_guardian = Guardian.new(invite.invited_by)
+          new_group_ids = invite.groups.pluck(:id) - current_user.group_users.pluck(:group_id)
+          new_group_ids.each do |id|
+            if group = Group.find_by(id: id)
+              if invite_by_guardian.can_edit_group?(group)
+                group.add(current_user)
+                added_to_group = true
+              end
+            end
+          end
+        end
+
+        if topic = invite.topics.first
+          new_guardian = Guardian.new(current_user)
+          return redirect_to(topic.url) if new_guardian.can_see?(topic)
+        elsif added_to_group
+          return redirect_to(path("/"))
+        end
+
+        return ensure_not_logged_in
+      end
+
       email = Email.obfuscate(invite.email)
 
       # Show email if the user already authenticated their email
diff --git a/spec/requests/invites_controller_spec.rb b/spec/requests/invites_controller_spec.rb
index 6d74c455e0..972715b644 100644
--- a/spec/requests/invites_controller_spec.rb
+++ b/spec/requests/invites_controller_spec.rb
@@ -57,6 +57,45 @@ describe InvitesController do
       end
     end
 
+    it 'adds logged in users to invite groups' do
+      group = Fabricate(:group)
+      group.add_owner(invite.invited_by)
+      InvitedGroup.create!(group: group, invite: invite)
+
+      sign_in(user)
+
+      get "/invites/#{invite.invite_key}"
+      expect(response).to redirect_to("/")
+      expect(user.reload.groups).to include(group)
+    end
+
+    it 'redirects logged in users to invite topic if they can see it' do
+      topic = Fabricate(:topic)
+      TopicInvite.create!(topic: topic, invite: invite)
+
+      sign_in(user)
+
+      get "/invites/#{invite.invite_key}"
+      expect(response).to redirect_to(topic.url)
+    end
+
+    it 'adds logged in user to group and redirects them to invite topic' do
+      group = Fabricate(:group)
+      group.add_owner(invite.invited_by)
+      secured_category = Fabricate(:category)
+      secured_category.permissions = { group.name => :full }
+      secured_category.save!
+      topic = Fabricate(:topic, category: secured_category)
+      TopicInvite.create!(invite: invite, topic: topic)
+      InvitedGroup.create!(invite: invite, group: group)
+
+      sign_in(user)
+
+      get "/invites/#{invite.invite_key}"
+      expect(user.reload.groups).to include(group)
+      expect(response).to redirect_to(topic.url)
+    end
+
     it 'fails for logged in users' do
       sign_in(Fabricate(:user))