diff --git a/config/sidekiq_queues.yml b/config/sidekiq_queues.yml
index 84cbf015a16e963da9cbc557f85f27d4b7c90a0a..6f04bb70a6ba2b71737ce3683ce57d5bbe3d3de3 100644
--- a/config/sidekiq_queues.yml
+++ b/config/sidekiq_queues.yml
@@ -479,6 +479,8 @@
   - 1
 - - gitlab_subscriptions_members_record_last_activity
   - 1
+- - gitlab_subscriptions_members_updated
+  - 1
 - - gitlab_subscriptions_refresh_seats
   - 1
 - - gitlab_subscriptions_seat_assignments_group_links_create_or_update_seats
diff --git a/ee/app/events/members/updated_event.rb b/ee/app/events/members/updated_event.rb
new file mode 100644
index 0000000000000000000000000000000000000000..608f3e1a13d7e06280b16397adc808f4d2686e1b
--- /dev/null
+++ b/ee/app/events/members/updated_event.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Members
+  class UpdatedEvent < ::Gitlab::EventStore::Event
+    def schema
+      {
+        'type' => 'object',
+        'required' => %w[source_id source_type user_id],
+        'properties' => {
+          'root_namespace_id' => { 'type' => 'integer' },
+          'source_id' => { 'type' => 'integer' },
+          'source_type' => { 'type' => 'string' },
+          'user_id' => { 'type' => %w[integer null] }
+        }
+      }
+    end
+  end
+end
diff --git a/ee/app/models/ee/member.rb b/ee/app/models/ee/member.rb
index e5d1cd7523c9adc676f67b9b643d254c205cc0b7..523c18a94b8311ee28a7e3e1be75b5124d4eb5e2 100644
--- a/ee/app/models/ee/member.rb
+++ b/ee/app/models/ee/member.rb
@@ -77,6 +77,8 @@ module Member
       end
 
       scope :order_access_level_desc, -> { order(access_level: :desc) }
+
+      after_commit :publish_member_updated_event, on: [:create, :update], if: -> { user_id.present? }
     end
 
     class_methods do
@@ -328,5 +330,15 @@ def after_accept_request
 
       update_user_group_member_roles
     end
+
+    def publish_member_updated_event
+      ::Gitlab::EventStore.publish(
+        ::Members::UpdatedEvent.new(data: {
+          source_id: source.id,
+          source_type: source.class.name,
+          user_id: user_id
+        })
+      )
+    end
   end
 end
diff --git a/ee/app/services/gitlab_subscriptions/seat_assignment_service.rb b/ee/app/services/gitlab_subscriptions/seat_assignment_service.rb
new file mode 100644
index 0000000000000000000000000000000000000000..3089cfc5dbc67023aaf5c0ebfe8b16164f2e3447
--- /dev/null
+++ b/ee/app/services/gitlab_subscriptions/seat_assignment_service.rb
@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+module GitlabSubscriptions
+  class SeatAssignmentService
+    def initialize(user, namespace)
+      @user = user
+      @namespace = namespace&.root_ancestor
+    end
+
+    def execute
+      return ServiceResponse.error(message: 'Invalid params') unless user && namespace&.group_namespace?
+      return ServiceResponse.error(message: 'User is not a member') unless user_is_a_member?
+
+      seat_assignment = find_seat_assignment || build_seat_assignment
+
+      seat_type = GitlabSubscriptions::SeatTypeCalculator.execute(user, namespace)
+      seat_assignment.update(seat_type: seat_type)
+
+      if seat_assignment.save
+        ServiceResponse.success(message: 'Seat assignment updated')
+      else
+        ServiceResponse.error(message: 'Unable to update seat assignment')
+      end
+    end
+
+    private
+
+    attr_reader :user, :namespace
+
+    def find_seat_assignment
+      GitlabSubscriptions::SeatAssignment.find_by_namespace_and_user(namespace, user)
+    end
+
+    def build_seat_assignment
+      GitlabSubscriptions::SeatAssignment.new(
+        namespace: namespace,
+        user: user,
+        organization_id: namespace.organization_id || Organizations::Organization::DEFAULT_ORGANIZATION_ID
+      )
+    end
+
+    def user_is_a_member?
+      ::Member.in_hierarchy(namespace).with_user(user).exists?
+    end
+  end
+end
diff --git a/ee/app/workers/all_queues.yml b/ee/app/workers/all_queues.yml
index 4e687b14e2ccb3bfe80c07139bf58222b91c073b..152241fdeb14004a79fa4b7c5dff7f39e5fd7d8c 100644
--- a/ee/app/workers/all_queues.yml
+++ b/ee/app/workers/all_queues.yml
@@ -2443,6 +2443,16 @@
   :idempotent: true
   :tags: []
   :queue_namespace:
+- :name: gitlab_subscriptions_members_updated
+  :worker_name: GitlabSubscriptions::Members::UpdatedWorker
+  :feature_category: :seat_cost_management
+  :has_external_dependencies: false
+  :urgency: :low
+  :resource_boundary: :unknown
+  :weight: 1
+  :idempotent: true
+  :tags: []
+  :queue_namespace:
 - :name: gitlab_subscriptions_refresh_seats
   :worker_name: GitlabSubscriptions::RefreshSeatsWorker
   :feature_category: :seat_cost_management
diff --git a/ee/app/workers/gitlab_subscriptions/members/updated_worker.rb b/ee/app/workers/gitlab_subscriptions/members/updated_worker.rb
new file mode 100644
index 0000000000000000000000000000000000000000..a1e759237eb167a29d3409aeff77a11486f19483
--- /dev/null
+++ b/ee/app/workers/gitlab_subscriptions/members/updated_worker.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+module GitlabSubscriptions
+  module Members
+    class UpdatedWorker
+      include Gitlab::EventStore::Subscriber
+
+      DEFER_ON_HEALTH_DELAY = 1.minute
+
+      data_consistency :delayed
+      feature_category :seat_cost_management
+      urgency :low
+
+      defer_on_database_health_signal :gitlab_main, [:users, :namespaces, :members], DEFER_ON_HEALTH_DELAY
+
+      idempotent!
+      deduplicate :until_executing, including_scheduled: true
+
+      def handle_event(event)
+        user = ::User.find_by_id(event.data[:user_id])
+        namespace = ::Namespace.find_by_id(event.data[:root_namespace_id])
+
+        return unless user && namespace&.group_namespace?
+
+        ::GitlabSubscriptions::SeatAssignmentService.new(user, namespace).execute
+      end
+    end
+  end
+end
diff --git a/ee/lib/ee/gitlab/event_store.rb b/ee/lib/ee/gitlab/event_store.rb
index 6e7dd3fca0fc57771e7ec63b9d74ac9ea194e3e4..0938896f4b1d41e11a73fc7693197eed0f5bf405 100644
--- a/ee/lib/ee/gitlab/event_store.rb
+++ b/ee/lib/ee/gitlab/event_store.rb
@@ -69,6 +69,7 @@ def configure!(store)
             if: ->(_) {
               ::Gitlab::CurrentSettings.enable_member_promotion_management?
             }
+          store.subscribe ::GitlabSubscriptions::Members::UpdatedWorker, to: ::Members::UpdatedEvent
 
           register_threat_insights_subscribers(store)
           register_security_policy_subscribers(store)