diff --git a/app/helpers/integrations_helper.rb b/app/helpers/integrations_helper.rb
index ee373452100da7ee84cca58f4ba9e0f125051556..795ef3098444ee11575610540903259af424a66a 100644
--- a/app/helpers/integrations_helper.rb
+++ b/app/helpers/integrations_helper.rb
@@ -205,6 +205,7 @@ def integration_webhook_event_human_name(event)
       project_events: s_('Webhooks|Project events'),
       push_events: _('Push events'),
       releases_events: s_('Webhooks|Releases events'),
+      milestone_events: s_('Webhooks|Milestone events'),
       repository_update_events: _('Repository update events'),
       resource_access_token_events: s_('Webhooks|Project or group access token events'),
       subgroup_events: s_('Webhooks|Subgroup events'),
diff --git a/app/models/group.rb b/app/models/group.rb
index ea17559d073399b23c8cde0c5b8d5345f0a4bff0..74ad36562a8a4415c52ef92bd95e89020aecc993 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -1132,6 +1132,11 @@ def supports_group_work_items?
     false
   end
 
+  # overriden in EE
+  def has_active_hooks?(hooks_scope = :push_hooks)
+    false
+  end
+
   # overriden in EE
   def enterprise_user_settings_available?(user = nil)
     false
diff --git a/app/services/milestones/base_service.rb b/app/services/milestones/base_service.rb
index ecfe7db325e51436c3c0b570de8f195ac40a4155..6c5451d7fd8da4ebdd8067de6fd996da7e705628 100644
--- a/app/services/milestones/base_service.rb
+++ b/app/services/milestones/base_service.rb
@@ -16,8 +16,6 @@ def initialize(parent, user, params = {})
     private
 
     def execute_hooks(milestone, action)
-      # At the moment, only project milestones support webhooks, not group milestones
-      return unless milestone.project_milestone?
       return unless milestone.parent.has_active_hooks?(:milestone_hooks)
 
       payload = Gitlab::DataBuilder::Milestone.build(milestone, action)
diff --git a/app/services/milestones/close_service.rb b/app/services/milestones/close_service.rb
index 616c6d85b7c55a1cbebaa7ec5cb423933a02e5f7..968494eeaac54867c32c33dea555cc32f146cdda 100644
--- a/app/services/milestones/close_service.rb
+++ b/app/services/milestones/close_service.rb
@@ -3,8 +3,8 @@
 module Milestones
   class CloseService < Milestones::BaseService
     def execute(milestone)
-      if milestone.close && milestone.project_milestone?
-        event_service.close_milestone(milestone, current_user)
+      if milestone.close
+        event_service.close_milestone(milestone, current_user) if milestone.project_milestone?
         execute_hooks(milestone, 'close')
       end
 
diff --git a/app/services/milestones/create_service.rb b/app/services/milestones/create_service.rb
index d8a9be6aafebd451d58d26b0e4dac489caba9118..a8d43cbcf1563e73efaa149b0987b035e4dd1ffd 100644
--- a/app/services/milestones/create_service.rb
+++ b/app/services/milestones/create_service.rb
@@ -7,8 +7,8 @@ def execute
 
       before_create(milestone)
 
-      if milestone.save && milestone.project_milestone?
-        event_service.open_milestone(milestone, current_user)
+      if milestone.save
+        event_service.open_milestone(milestone, current_user) if milestone.project_milestone?
         execute_hooks(milestone, 'create')
       end
 
diff --git a/app/services/milestones/destroy_service.rb b/app/services/milestones/destroy_service.rb
index dc605472e37bf0b10b820376c31c9baef1a6a0fe..39d32709ec622af696f595112b4a4a0928456852 100644
--- a/app/services/milestones/destroy_service.rb
+++ b/app/services/milestones/destroy_service.rb
@@ -14,7 +14,7 @@ def execute(milestone)
 
       return unless milestone.destroyed?
 
-      execute_hooks(milestone, 'delete') if milestone.project_milestone?
+      execute_hooks(milestone, 'delete')
       milestone
     end
 
diff --git a/app/services/milestones/reopen_service.rb b/app/services/milestones/reopen_service.rb
index a4a9ccfd4011dc5371cea76c465bbabd59f6cebb..13e138bd5615de9c5bc6fc56dcb8fccf99b24b28 100644
--- a/app/services/milestones/reopen_service.rb
+++ b/app/services/milestones/reopen_service.rb
@@ -3,8 +3,8 @@
 module Milestones
   class ReopenService < Milestones::BaseService
     def execute(milestone)
-      if milestone.activate && milestone.project_milestone?
-        event_service.reopen_milestone(milestone, current_user)
+      if milestone.activate
+        event_service.reopen_milestone(milestone, current_user) if milestone.project_milestone?
         execute_hooks(milestone, 'reopen')
       end
 
diff --git a/doc/api/group_webhooks.md b/doc/api/group_webhooks.md
index 28021ac2e0b16374e719b763466845e81260f8c8..cbb57e2ac3b58e5814b0c6c201f01b216e876c1a 100644
--- a/doc/api/group_webhooks.md
+++ b/doc/api/group_webhooks.md
@@ -70,6 +70,7 @@ Example response:
     "deployment_events": false,
     "feature_flag_events": false,
     "releases_events": false,
+    "milestone_events": false,
     "subgroup_events": false,
     "emoji_events": false,
     "resource_access_token_events": false,
@@ -130,6 +131,7 @@ Example response:
   "deployment_events": true,
   "feature_flag_events": false,
   "releases_events": true,
+  "milestone_events": false,
   "subgroup_events": true,
   "member_events": true,
   "project_events": true,
@@ -500,6 +502,7 @@ Supported attributes:
 | `deployment_events`          | boolean        | no       | Trigger hook on deployment events. |
 | `feature_flag_events`        | boolean        | no       | Trigger hook on feature flag events. |
 | `releases_events`            | boolean        | no       | Trigger hook on release events. |
+| `milestone_events`           | boolean        | no       | Trigger hook on milestone events. |
 | `subgroup_events`            | boolean        | no       | Trigger hook on subgroup events. |
 | `member_events`              | boolean        | no       | Trigger hook on member events. |
 | `project_events`             | boolean        | no       | Trigger hook on project events. |
@@ -543,6 +546,7 @@ Example response:
   "deployment_events": true,
   "feature_flag_events": true,
   "releases_events": true,
+  "milestone_events": true,
   "subgroup_events": true,
   "member_events": true,
   "project_events": true,
@@ -589,6 +593,7 @@ Supported attributes:
 | `deployment_events`          | boolean        | no       | Trigger hook on deployment events. |
 | `feature_flag_events`        | boolean        | no       | Trigger hook on feature flag events. |
 | `releases_events`            | boolean        | no       | Trigger hook on release events. |
+| `milestone_events`           | boolean        | no       | Trigger hook on milestone events. |
 | `subgroup_events`            | boolean        | no       | Trigger hook on subgroup events. |
 | `member_events`              | boolean        | no       | Trigger hook on member events. |
 | `project_events`             | boolean        | no       | Trigger hook on project events. |
@@ -633,6 +638,7 @@ Example response:
   "deployment_events": true,
   "feature_flag_events": true,
   "releases_events": true,
+  "milestone_events": true,
   "subgroup_events": true,
   "member_events": true,
   "project_events": true,
@@ -699,7 +705,7 @@ POST /groups/:id/hooks/:hook_id/test/:trigger
 |-----------|-------------------|----------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
 | `hook_id` | integer           | Yes      | The ID of the group hook.                                                                                                                                                                                                                                  |
 | `id`      | integer or string | Yes      | The ID or [URL-encoded path of the group](rest/_index.md#namespaced-paths).                                                                                                                                                                           |
-| `trigger` | string            | Yes      | One of `push_events`, `tag_push_events`, `issues_events`, `confidential_issues_events`, `note_events`, `merge_requests_events`, `job_events`, `pipeline_events`, `wiki_page_events`, `releases_events`, `emoji_events`, or `resource_access_token_events`. |
+| `trigger` | string            | Yes      | One of `push_events`, `tag_push_events`, `issues_events`, `confidential_issues_events`, `note_events`, `merge_requests_events`, `job_events`, `pipeline_events`, `wiki_page_events`, `releases_events`, `milestone_events`, `emoji_events`, or `resource_access_token_events`. |
 
 Example request:
 
diff --git a/ee/app/models/ee/group.rb b/ee/app/models/ee/group.rb
index 60a317fc0a381cf34c85f9083b03211c62d16021..c9ff98c994475e5fffc35c23fe9cf4537f5c1ad9 100644
--- a/ee/app/models/ee/group.rb
+++ b/ee/app/models/ee/group.rb
@@ -812,6 +812,12 @@ def execute_hooks(data, hooks_scope)
       execute_async_hooks(group_hooks, hooks_scope, data)
     end
 
+    override :has_active_hooks?
+    def has_active_hooks?(hooks_scope = :push_hooks)
+      feature_available?(:group_webhooks) &&
+        GroupHook.where(group_id: self_and_ancestors).hooks_for(hooks_scope).any?
+    end
+
     override :git_transfer_in_progress?
     def git_transfer_in_progress?
       reference_counter(type: ::Gitlab::GlRepository::WIKI).value > 0
diff --git a/ee/app/models/hooks/group_hook.rb b/ee/app/models/hooks/group_hook.rb
index 2026d1ec685d96e2abbd855195a074857b723dd7..f87861ee3adc1ae3e4095509684ad9f667c91905 100644
--- a/ee/app/models/hooks/group_hook.rb
+++ b/ee/app/models/hooks/group_hook.rb
@@ -28,6 +28,7 @@ class GroupHook < WebHook
     :project_hooks,
     :push_hooks,
     :release_hooks,
+    :milestone_hooks,
     :resource_access_token_hooks,
     :subgroup_hooks,
     :tag_push_hooks,
diff --git a/ee/lib/api/group_hooks.rb b/ee/lib/api/group_hooks.rb
index 81059504e03a2688c612f0cdfdb4dcf96adb0154..f58e5fe684394b8cf637fc63ec2610c0fc81a2aa 100644
--- a/ee/lib/api/group_hooks.rb
+++ b/ee/lib/api/group_hooks.rb
@@ -40,6 +40,7 @@ def hook_scope
         optional :deployment_events, type: Boolean, desc: "Trigger hook on deployment events"
         optional :feature_flag_events, type: Boolean, desc: "Trigger hook on feature flag events"
         optional :releases_events, type: Boolean, desc: "Trigger hook on release events"
+        optional :milestone_events, type: Boolean, desc: "Trigger hook on milestone events"
         optional :subgroup_events, type: Boolean, desc: "Trigger hook on subgroup events"
         optional :emoji_events, type: Boolean, desc: "Trigger hook on emoji events"
         optional :resource_access_token_events, type: Boolean, desc: "Trigger hook on group access token expiry events"
diff --git a/ee/lib/ee/api/entities/group_hook.rb b/ee/lib/ee/api/entities/group_hook.rb
index b897c30fc3b07e64d8931fedb4aafe1fef5e124f..614be2a453f4946eea1016be0888c32c2cc85add 100644
--- a/ee/lib/ee/api/entities/group_hook.rb
+++ b/ee/lib/ee/api/entities/group_hook.rb
@@ -15,6 +15,7 @@ class GroupHook < ::API::Entities::Hook
         expose :deployment_events, documentation: { type: 'boolean' }
         expose :feature_flag_events, documentation: { type: 'boolean' }
         expose :releases_events, documentation: { type: 'boolean' }
+        expose :milestone_events, documentation: { type: 'boolean' }
         expose :subgroup_events, documentation: { type: 'boolean' }
         expose :emoji_events, documentation: { type: 'boolean' }
         expose :resource_access_token_events, documentation: { type: 'boolean' }
diff --git a/ee/lib/ee/gitlab/hook_data/milestone_builder.rb b/ee/lib/ee/gitlab/hook_data/milestone_builder.rb
new file mode 100644
index 0000000000000000000000000000000000000000..fb77f38984df4e1dda98b386b4e0577c064b2c17
--- /dev/null
+++ b/ee/lib/ee/gitlab/hook_data/milestone_builder.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+module EE
+  module Gitlab
+    module HookData
+      module MilestoneBuilder
+        extend ActiveSupport::Concern
+
+        EE_SAFE_HOOK_ATTRIBUTES = %i[
+          group_id
+        ].freeze
+
+        class_methods do
+          extend ::Gitlab::Utils::Override
+
+          override :safe_hook_attributes
+          def safe_hook_attributes
+            super + EE_SAFE_HOOK_ATTRIBUTES
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/ee/spec/controllers/groups/hooks_controller_spec.rb b/ee/spec/controllers/groups/hooks_controller_spec.rb
index 7d2a1ad029fc311cde69b965abac8fdd76abaa56..9d44d88aa5ca7a0519b7b1dd68f039a261433a14 100644
--- a/ee/spec/controllers/groups/hooks_controller_spec.rb
+++ b/ee/spec/controllers/groups/hooks_controller_spec.rb
@@ -141,6 +141,7 @@ def it_renders_correctly
             wiki_page_events: true,
             deployment_events: true,
             releases_events: true,
+            milestone_events: true,
             member_events: true,
             subgroup_events: true,
             url_variables: [
diff --git a/ee/spec/factories/group_hooks.rb b/ee/spec/factories/group_hooks.rb
index 71962ef291cb23359c5bbd72c72df1f0fab69210..53f09c0c50a72061acf0d111538c7c2198ade5b9 100644
--- a/ee/spec/factories/group_hooks.rb
+++ b/ee/spec/factories/group_hooks.rb
@@ -30,6 +30,7 @@
       project_events { true }
       wiki_page_events { true }
       releases_events { true }
+      milestone_events { true }
       subgroup_events { true }
       emoji_events { true }
       resource_access_token_events { true }
diff --git a/ee/spec/fixtures/api/schemas/public_api/v4/group_hook.json b/ee/spec/fixtures/api/schemas/public_api/v4/group_hook.json
index bc13fbd35d3ec224a87e6e9808a0a3e358c2c160..0300624eab1f83e60355eda0ae51a0cce5eff068 100644
--- a/ee/spec/fixtures/api/schemas/public_api/v4/group_hook.json
+++ b/ee/spec/fixtures/api/schemas/public_api/v4/group_hook.json
@@ -20,6 +20,7 @@
     "job_events",
     "deployment_events",
     "releases_events",
+    "milestone_events",
     "subgroup_events",
     "emoji_events",
     "feature_flag_events",
@@ -115,6 +116,9 @@
     "releases_events": {
       "type": "boolean"
     },
+    "milestone_events": {
+      "type": "boolean"
+    },
     "subgroup_events": {
       "type": "boolean"
     },
diff --git a/ee/spec/lib/ee/gitlab/hook_data/milestone_builder_spec.rb b/ee/spec/lib/ee/gitlab/hook_data/milestone_builder_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..794f30338b8645115515f983cb42caf52a230280
--- /dev/null
+++ b/ee/spec/lib/ee/gitlab/hook_data/milestone_builder_spec.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::HookData::MilestoneBuilder, feature_category: :webhooks do
+  let_it_be(:milestone) { create(:milestone) }
+
+  let(:builder) { described_class.new(milestone) }
+
+  describe '.safe_hook_attributes' do
+    subject(:safe_attribute_keys) { described_class.safe_hook_attributes }
+
+    it 'includes safe attribute' do
+      expected_safe_attribute_keys = %i[
+        id
+        iid
+        title
+        description
+        state
+        created_at
+        updated_at
+        due_date
+        start_date
+        project_id
+        group_id
+      ].freeze
+
+      expect(safe_attribute_keys).to match_array(expected_safe_attribute_keys)
+    end
+  end
+end
diff --git a/ee/spec/models/ee/group_spec.rb b/ee/spec/models/ee/group_spec.rb
index 0d3daa53f95c464bf717bc84a726ef4aa960360e..4dc1fdd7f0d1b6ef936988c77c63a5b5a032bbdb 100644
--- a/ee/spec/models/ee/group_spec.rb
+++ b/ee/spec/models/ee/group_spec.rb
@@ -2980,6 +2980,71 @@ def webhook_headers
     end
   end
 
+  describe '#has_active_hooks?' do
+    let_it_be_with_reload(:parent_group) { create(:group) }
+    let_it_be_with_reload(:group) { create(:group, parent: parent_group) }
+    let(:hooks_scope) { :push_hooks }
+
+    subject { group.has_active_hooks?(hooks_scope) }
+
+    context 'when group_webhooks feature is available' do
+      before do
+        stub_licensed_features(group_webhooks: true)
+      end
+
+      context 'when no hooks exist' do
+        it 'returns false' do
+          expect(subject).to be false
+        end
+      end
+
+      context 'when hook exists for the group' do
+        let_it_be_with_reload(:group_hook) { create(:group_hook, group: group, push_events: true) }
+
+        it 'returns true for push_hooks scope' do
+          expect(subject).to be true
+        end
+
+        context 'with different hook scope' do
+          let(:hooks_scope) { :issues_hooks }
+
+          it 'returns false' do
+            expect(subject).to be false
+          end
+        end
+      end
+
+      context 'when hook exists for the ancestor group' do
+        let!(:parent_hook) { create(:group_hook, group: parent_group, push_events: true) }
+
+        it 'returns true when checking group that inherits hooks from ancestor' do
+          expect(subject).to be true
+        end
+      end
+
+      context 'when hook exists for unrelated group' do
+        let!(:unrelated_group) { create(:group) }
+        let!(:unrelated_group_hook) { create(:group_hook, group: unrelated_group, push_events: true) }
+
+        it 'returns false' do
+          expect(subject).to be false
+        end
+      end
+    end
+
+    context 'when group_webhooks feature is not available' do
+      before do
+        stub_licensed_features(group_webhooks: false)
+      end
+
+      let!(:group_hook) { create(:group_hook, group: group, push_events: true) }
+
+      it 'returns false even when hook exists' do
+        expect(subject).to be false
+      end
+    end
+  end
+
   context 'when resource access token hooks for expiry notification' do
     let(:group) { create(:group) }
     let(:group_hook) { create(:group_hook, group: group, resource_access_token_events: true) }
diff --git a/ee/spec/requests/api/group_hooks_spec.rb b/ee/spec/requests/api/group_hooks_spec.rb
index 2e40485306fddc7959dbd7696fdda54cfe2e5cec..f15d0749ef128f98bdbf36d97cbfb80cc4fe3c27 100644
--- a/ee/spec/requests/api/group_hooks_spec.rb
+++ b/ee/spec/requests/api/group_hooks_spec.rb
@@ -53,6 +53,7 @@ def event_names
         wiki_page_events
         deployment_events
         releases_events
+        milestone_events
         subgroup_events
         feature_flag_events
         emoji_events
diff --git a/ee/spec/services/milestones/close_service_spec.rb b/ee/spec/services/milestones/close_service_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..d423ddad6090e22f3c7d9b5f6e0bf98b444618fa
--- /dev/null
+++ b/ee/spec/services/milestones/close_service_spec.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Milestones::CloseService, feature_category: :team_planning do
+  let_it_be(:user) { create(:user) }
+
+  subject(:service) { described_class.new(container, user, {}) }
+
+  describe '#execute' do
+    context 'on group milestones' do
+      let_it_be(:container) { create(:group, maintainers: user) }
+
+      let(:milestone) { create(:milestone, title: 'Milestone v1.0', group: container) }
+
+      context 'when group webhooks are available' do
+        before do
+          stub_licensed_features(group_webhooks: true)
+        end
+
+        context 'when group has active milestone hooks' do
+          before do
+            allow(container).to receive(:has_active_hooks?).with(:milestone_hooks).and_return(true)
+          end
+
+          it_behaves_like 'closes the milestone', with_hooks: true, with_event: false
+        end
+
+        context 'when group has no active milestone hooks' do
+          it_behaves_like 'closes the milestone', with_hooks: false, with_event: false
+        end
+      end
+
+      context 'when group webhooks are not available' do
+        it_behaves_like 'closes the milestone', with_hooks: false, with_event: false
+      end
+    end
+  end
+end
diff --git a/ee/spec/services/milestones/create_service_spec.rb b/ee/spec/services/milestones/create_service_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..449d3cf23c68f4e980729cc0b93d754e9fd6b877
--- /dev/null
+++ b/ee/spec/services/milestones/create_service_spec.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Milestones::CreateService, feature_category: :team_planning do
+  let_it_be(:params) { { title: 'New Milestone', description: 'Description' } }
+  let_it_be(:user) { create(:user) }
+
+  subject(:service) { described_class.new(container, user, params) }
+
+  describe '#execute' do
+    context 'on group milestones' do
+      let_it_be(:container) { create(:group, maintainers: user) }
+
+      context 'when group webhooks are available' do
+        before do
+          stub_licensed_features(group_webhooks: true)
+        end
+
+        context 'when group has active milestone hooks' do
+          before do
+            allow(container).to receive(:has_active_hooks?).with(:milestone_hooks).and_return(true)
+          end
+
+          it_behaves_like 'creates the milestone', with_hooks: true, with_event: false
+        end
+
+        context 'when group has no active milestone hooks' do
+          it_behaves_like 'creates the milestone', with_hooks: false, with_event: false
+        end
+      end
+
+      context 'when group webhooks are not available' do
+        it_behaves_like 'creates the milestone', with_hooks: false, with_event: false
+      end
+    end
+  end
+end
diff --git a/ee/spec/services/milestones/destroy_service_spec.rb b/ee/spec/services/milestones/destroy_service_spec.rb
index 2b93a9bcea6ce39ed9abe0b24fc92fccff5f0903..c31b181513fab2e186e02fd9a09755559e75df57 100644
--- a/ee/spec/services/milestones/destroy_service_spec.rb
+++ b/ee/spec/services/milestones/destroy_service_spec.rb
@@ -3,27 +3,67 @@
 require 'spec_helper'
 
 RSpec.describe Milestones::DestroyService, feature_category: :team_planning do
-  let(:user) { create(:user) }
-  let(:project) { create(:project, :repository) }
-  let(:milestone) { create(:milestone, title: 'Milestone v1.0', project: project) }
+  let_it_be(:user) { create(:user) }
 
-  before do
-    project.add_maintainer(user)
-  end
-
-  def service
-    described_class.new(project, user, {})
-  end
+  subject(:service) { described_class.new(container, user, {}) }
 
   describe '#execute' do
-    context 'with an existing merge request' do
-      let!(:issue) { create(:issue, project: project, milestone: milestone) }
-      let!(:merge_request) { create(:merge_request, source_project: project, milestone: milestone) }
+    context 'on project milestones' do
+      let_it_be(:container) { create(:project, :repository, maintainers: user) }
+
+      let(:milestone) { create(:milestone, title: 'Milestone v1.0', project: container) }
+
+      context 'with an existing merge request' do
+        let!(:issue) { create(:issue, project: container, milestone: milestone) }
+        let!(:merge_request) { create(:merge_request, source_project: container, milestone: milestone) }
+
+        it 'manually queues MergeRequests::SyncCodeOwnerApprovalRulesWorker jobs' do
+          expect(::MergeRequests::SyncCodeOwnerApprovalRulesWorker).to receive(:perform_async).with(merge_request.id)
+
+          service.execute(milestone)
+        end
+      end
+    end
+
+    context 'on group milestones' do
+      let_it_be(:container) { create(:group, maintainers: user) }
 
-      it 'manually queues MergeRequests::SyncCodeOwnerApprovalRulesWorker jobs' do
-        expect(::MergeRequests::SyncCodeOwnerApprovalRulesWorker).to receive(:perform_async).with(merge_request.id)
+      let(:milestone) { create(:milestone, title: 'Milestone v1.0', group: container) }
+
+      shared_examples 'deletes group-milestone' do |with_hooks:|
+        it 'conditionally executes webhooks and does not create a new event' do
+          if with_hooks
+            expect(milestone.parent).to receive(:execute_hooks).with(a_hash_including(action: 'delete'),
+              :milestone_hooks)
+          end
+
+          expect(Event).not_to receive(:new)
+
+          service.execute(milestone)
+          expect { milestone.reload }.to raise_error ActiveRecord::RecordNotFound
+        end
+      end
+
+      context 'when group webhooks are available' do
+        before do
+          stub_licensed_features(group_webhooks: true)
+        end
+
+        context 'when group has active milestone hooks' do
+          before do
+            allow(container).to receive(:has_active_hooks?).with(:milestone_hooks).and_return(true)
+          end
+
+          it_behaves_like 'deletes group-milestone', with_hooks: true
+        end
+
+        context 'when group has no active milestone hooks' do
+          it_behaves_like 'deletes group-milestone', with_hooks: false
+        end
+      end
 
-        service.execute(milestone)
+      context 'when group webhooks are not available' do
+        it_behaves_like 'deletes group-milestone', with_hooks: false
       end
     end
   end
diff --git a/ee/spec/services/milestones/reopen_service_spec.rb b/ee/spec/services/milestones/reopen_service_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..184e3cc8571c2b4a0802649490ff5548725d9254
--- /dev/null
+++ b/ee/spec/services/milestones/reopen_service_spec.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Milestones::ReopenService, feature_category: :team_planning do
+  let_it_be(:user) { create(:user) }
+
+  subject(:service) { described_class.new(container, user, {}) }
+
+  describe '#execute' do
+    context 'on group milestones' do
+      let_it_be(:container) { create(:group, maintainers: user) }
+
+      let(:milestone) { create(:milestone, :closed, title: 'Milestone v1.0', group: container) }
+
+      context 'when group webhooks are available' do
+        before do
+          stub_licensed_features(group_webhooks: true)
+        end
+
+        context 'when group has active milestone hooks' do
+          before do
+            allow(container).to receive(:has_active_hooks?).with(:milestone_hooks).and_return(true)
+          end
+
+          it_behaves_like 'reopens the milestone', with_hooks: true, with_event: false
+        end
+
+        context 'when group has no active milestone hooks' do
+          it_behaves_like 'reopens the milestone', with_hooks: false, with_event: false
+        end
+      end
+
+      context 'when group webhooks are not available' do
+        it_behaves_like 'reopens the milestone', with_hooks: false, with_event: false
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/data_builder/milestone.rb b/lib/gitlab/data_builder/milestone.rb
index 6f6e269c082513e6703b85d72261c9b2827ab0c2..ce9c017973e378985e2eb50022ab5c3f17501e3b 100644
--- a/lib/gitlab/data_builder/milestone.rb
+++ b/lib/gitlab/data_builder/milestone.rb
@@ -22,6 +22,7 @@ def build(milestone, action)
           object_kind: 'milestone',
           event_type: 'milestone',
           project: milestone.project&.hook_attrs,
+          group: milestone.group&.hook_attrs,
           object_attributes: milestone.hook_attrs,
           action: action
         }
diff --git a/lib/gitlab/hook_data/milestone_builder.rb b/lib/gitlab/hook_data/milestone_builder.rb
index f2022a956eb25b685cf5a794ed87c340b7c5dda2..3e523e3d4f71daaa1545e408f1c0042d6f662bcc 100644
--- a/lib/gitlab/hook_data/milestone_builder.rb
+++ b/lib/gitlab/hook_data/milestone_builder.rb
@@ -3,18 +3,20 @@
 module Gitlab
   module HookData
     class MilestoneBuilder < BaseBuilder
-      SAFE_HOOK_ATTRIBUTES = %i[
-        id
-        iid
-        title
-        description
-        state
-        created_at
-        updated_at
-        due_date
-        start_date
-        project_id
-      ].freeze
+      def self.safe_hook_attributes
+        %i[
+          id
+          iid
+          title
+          description
+          state
+          created_at
+          updated_at
+          due_date
+          start_date
+          project_id
+        ].freeze
+      end
 
       alias_method :milestone, :object
 
@@ -22,8 +24,10 @@ def build
         milestone
           .attributes
           .with_indifferent_access
-          .slice(*SAFE_HOOK_ATTRIBUTES)
+          .slice(*self.class.safe_hook_attributes)
       end
     end
   end
 end
+
+Gitlab::HookData::MilestoneBuilder.prepend_mod
diff --git a/locale/gitlab.pot b/locale/gitlab.pot
index 70b2265af9e8e812151c38860e2fe29a8ecc15d2..54d686a3d684eab1ded73e9f5f65a3335c8df530 100644
--- a/locale/gitlab.pot
+++ b/locale/gitlab.pot
@@ -70420,6 +70420,9 @@ msgstr ""
 msgid "Webhooks|Merge request events"
 msgstr ""
 
+msgid "Webhooks|Milestone events"
+msgstr ""
+
 msgid "Webhooks|Must match part of URL"
 msgstr ""
 
diff --git a/spec/helpers/integrations_helper_spec.rb b/spec/helpers/integrations_helper_spec.rb
index cd11007dc77d83e1a4d43a50ba83a93937a57d09..1e79bdeb3b1231cbc5fd78d1da1966c4c60b59f9 100644
--- a/spec/helpers/integrations_helper_spec.rb
+++ b/spec/helpers/integrations_helper_spec.rb
@@ -405,6 +405,7 @@ def relation
       :deployment_events | 'Deployment events'
       :feature_flag_events | 'Feature flag events'
       :releases_events | 'Releases events'
+      :milestone_events | 'Milestone events'
       :resource_access_token_events | 'Project or group access token events'
       :vulnerability_events | 'Vulnerability events'
     end
diff --git a/spec/lib/gitlab/hook_data/milestone_builder_spec.rb b/spec/lib/gitlab/hook_data/milestone_builder_spec.rb
index ef26dc9dd5d339bd58a03c59b67bab931298da52..7043428a17c8870474b911e51b2dbb39fc6901de 100644
--- a/spec/lib/gitlab/hook_data/milestone_builder_spec.rb
+++ b/spec/lib/gitlab/hook_data/milestone_builder_spec.rb
@@ -11,7 +11,7 @@
     subject(:data) { builder.build }
 
     it 'includes safe attributes' do
-      expect(data.keys).to match_array(described_class::SAFE_HOOK_ATTRIBUTES.map(&:to_s))
+      expect(data.keys).to match_array(described_class.safe_hook_attributes.map(&:to_s))
     end
 
     it 'returns indifferent access hash' do
diff --git a/spec/models/group_spec.rb b/spec/models/group_spec.rb
index b55ee1607bf69abb241585e102fad54cff372a9e..3840fde252d59b29d1229095561d7b9c1429f05b 100644
--- a/spec/models/group_spec.rb
+++ b/spec/models/group_spec.rb
@@ -4373,7 +4373,21 @@ def define_cache_expectations(cache_key)
 
     subject { group.supports_group_work_items? }
 
-    it { is_expected.to be false }
+    it 'returns false' do
+      expect(subject).to be false
+    end
+  end
+
+  describe '#has_active_hooks?' do
+    let(:group) { build(:group) }
+
+    subject { group.has_active_hooks? }
+
+    # Would work in plain CE-version since it's implementation always returns false.
+    # Would work in EE-version since licensed features are disabled for specs in specs/ by deafult.
+    it 'returns false' do
+      expect(subject).to be false
+    end
   end
 
   describe '#glql_load_on_click_feature_flag_enabled?' do
diff --git a/spec/requests/api/project_hooks_spec.rb b/spec/requests/api/project_hooks_spec.rb
index 16f7e07ede920b0273c0c5f472d7f5c6af8987de..f055cdea268031240c887f1e34623d46d9fc148c 100644
--- a/spec/requests/api/project_hooks_spec.rb
+++ b/spec/requests/api/project_hooks_spec.rb
@@ -58,6 +58,7 @@ def event_names
         deployment_events
         feature_flag_events
         releases_events
+        milestone_events
         emoji_events
         resource_access_token_events
       ]
diff --git a/spec/services/milestones/close_service_spec.rb b/spec/services/milestones/close_service_spec.rb
index 2c0caa38bb6ec3436612cffb0af59fd218f654da..0eee799f09f14e2c1a8aecb71ff3a0552686eb13 100644
--- a/spec/services/milestones/close_service_spec.rb
+++ b/spec/services/milestones/close_service_spec.rb
@@ -3,16 +3,13 @@
 require 'spec_helper'
 
 RSpec.describe Milestones::CloseService, feature_category: :team_planning do
-  let(:user) { create(:user) }
-  let(:project) { create(:project) }
-  let(:milestone) { create(:milestone, title: "Milestone v1.2", project: project) }
+  describe '#execute' do
+    let_it_be(:user) { create(:user) }
+    let_it_be_with_reload(:project) { create(:project, maintainers: user) }
 
-  before do
-    project.add_maintainer(user)
-  end
+    let(:milestone) { create(:milestone, title: 'Milestone v1.2', project: project) }
 
-  describe '#execute' do
-    let(:service) { described_class.new(project, user, {}) }
+    subject(:service) { described_class.new(project, user, {}) }
 
     context 'when service is called before test suite' do
       before do
@@ -31,36 +28,17 @@
       end
     end
 
-    shared_examples 'closes the milestone' do |with_project_hooks:|
-      it 'executes hooks with close action and creates new event' do
-        expect(service).to receive(:execute_hooks).with(milestone, 'close').and_call_original
-        expect(project).to receive(:execute_hooks).with(kind_of(Hash), :milestone_hooks) if with_project_hooks
-
-        expect { service.execute(milestone) }.to change { Event.count }.by(1)
-      end
-    end
-
-    shared_examples 'does not close the milestone' do
-      it 'does not execute hooks and does not create new event' do
-        expect(service).not_to receive(:execute_hooks)
-
-        expect { service.execute(milestone) }.not_to change { Event.count }
-      end
-    end
-
     context 'when milestone is successfully closed' do
       context 'when project has active milestone hooks' do
-        let(:project) do
-          create(:project).tap do |project|
-            create(:project_hook, project: project, milestone_events: true)
-          end
+        before do
+          allow(project).to receive(:has_active_hooks?).with(:milestone_hooks).and_return(true)
         end
 
-        it_behaves_like 'closes the milestone', with_project_hooks: true
+        it_behaves_like 'closes the milestone', with_hooks: true, with_event: true
       end
 
       context 'when project has no active milestone hooks' do
-        it_behaves_like 'closes the milestone', with_project_hooks: false
+        it_behaves_like 'closes the milestone', with_hooks: false, with_event: true
       end
     end
 
@@ -68,14 +46,12 @@
       context 'when milestone is already closed' do
         let(:milestone) { create(:milestone, :closed, project: project) }
 
-        it_behaves_like 'does not close the milestone'
-      end
-
-      context 'when milestone is a group milestone' do
-        let(:group) { create(:group) }
-        let(:milestone) { create(:milestone, group: group) }
+        it 'does not execute hooks and does not create new event' do
+          expect(service).not_to receive(:execute_hooks)
+          expect(Event).not_to receive(:new)
 
-        it_behaves_like 'does not close the milestone'
+          expect { service.execute(milestone) }.not_to change { milestone.state }
+        end
       end
     end
   end
diff --git a/spec/services/milestones/create_service_spec.rb b/spec/services/milestones/create_service_spec.rb
index 1999b1d40392bb7befdea7614f188a0194150a80..c871433384ff050b05db838a21381f6433e66c40 100644
--- a/spec/services/milestones/create_service_spec.rb
+++ b/spec/services/milestones/create_service_spec.rb
@@ -4,15 +4,15 @@
 
 RSpec.describe Milestones::CreateService, feature_category: :team_planning do
   let_it_be(:user) { create(:user) }
-  let_it_be(:project) { create(:project) }
+  let_it_be(:container) { create(:project) }
   let_it_be(:params) { { title: 'New Milestone', description: 'Description' } }
 
-  subject(:create_milestone) { described_class.new(project, user, params) }
+  subject(:service) { described_class.new(container, user, params) }
 
   describe '#execute' do
     context 'when milestone is saved successfully' do
       it 'creates a new milestone' do
-        expect { create_milestone.execute }.to change { Milestone.count }.by(1)
+        expect { service.execute }.to change { Milestone.count }.by(1)
       end
 
       it 'opens the milestone if it is a project milestone' do
@@ -20,37 +20,26 @@
           expect(instance).to receive(:open_milestone)
         end
 
-        create_milestone.execute
+        service.execute
       end
 
       it 'returns the created milestone' do
-        milestone = create_milestone.execute
+        milestone = service.execute
         expect(milestone).to be_a(Milestone)
         expect(milestone.title).to eq('New Milestone')
         expect(milestone.description).to eq('Description')
       end
 
-      shared_examples 'creates the milestone' do |with_project_hooks:|
-        it 'executes hooks with create action and creates new event' do
-          expect(create_milestone).to receive(:execute_hooks).with(kind_of(Milestone), 'create').and_call_original
-          expect(project).to receive(:execute_hooks).with(kind_of(Hash), :milestone_hooks) if with_project_hooks
-
-          expect { create_milestone.execute }.to change { Event.count }.by(1)
-        end
-      end
-
       context 'when project has active milestone hooks' do
-        let(:project) do
-          create(:project).tap do |project|
-            create(:project_hook, project: project, milestone_events: true)
-          end
+        before do
+          allow(container).to receive(:has_active_hooks?).with(:milestone_hooks).and_return(true)
         end
 
-        it_behaves_like 'creates the milestone', with_project_hooks: true
+        it_behaves_like 'creates the milestone', with_hooks: true, with_event: true
       end
 
       context 'when project has no active milestone hooks' do
-        it_behaves_like 'creates the milestone', with_project_hooks: false
+        it_behaves_like 'creates the milestone', with_hooks: false, with_event: true
       end
     end
 
@@ -62,47 +51,32 @@
       end
 
       it 'does not create a new milestone' do
-        expect { create_milestone.execute }.not_to change { Milestone.count }
+        expect { service.execute }.not_to change { Milestone.count }
       end
 
       it 'does not open the milestone' do
         expect(EventCreateService).not_to receive(:open_milestone)
 
-        create_milestone.execute
+        service.execute
       end
 
       it 'does not execute hooks and does not create new event' do
-        expect(create_milestone).not_to receive(:execute_hooks)
+        expect(service).not_to receive(:execute_hooks)
 
-        expect { create_milestone.execute }.not_to change { Event.count }
+        expect { service.execute }.not_to change { Event.count }
       end
 
       it 'returns the unsaved milestone' do
-        milestone = create_milestone.execute
+        milestone = service.execute
         expect(milestone).to be_a(Milestone)
         expect(milestone.title).to eq('New Milestone')
         expect(milestone.persisted?).to be_falsey
       end
     end
 
-    context 'when milestone is a group milestone' do
-      let(:group) { create(:group) }
-      let(:group_service) { described_class.new(group, user, params) }
-
-      it 'does not execute hooks for group milestones' do
-        milestone = build(:milestone, group: group)
-        allow(milestone).to receive(:save).and_return(true)
-        allow(group_service).to receive(:build_milestone).and_return(milestone)
-
-        expect(group).not_to receive(:execute_hooks)
-
-        group_service.execute
-      end
-    end
-
     it 'calls before_create method' do
-      expect(create_milestone).to receive(:before_create)
-      create_milestone.execute
+      expect(service).to receive(:before_create)
+      service.execute
     end
   end
 
diff --git a/spec/services/milestones/destroy_service_spec.rb b/spec/services/milestones/destroy_service_spec.rb
index c76edd2648c361276265637c8326268b6233e839..1e83fa4c5701ed80bad6b53e5a029f364b09384d 100644
--- a/spec/services/milestones/destroy_service_spec.rb
+++ b/spec/services/milestones/destroy_service_spec.rb
@@ -27,7 +27,8 @@
             updated_attributes: %w[milestone_id]
           )
 
-        milestone.reload
+        expect { milestone.reload }.to raise_error ActiveRecord::RecordNotFound
+
         issues.each do |issue|
           expect(issue.reload.milestone).to be_nil
         end
@@ -36,7 +37,7 @@
     end
 
     context 'on project milestones' do
-      let_it_be_with_reload(:milestone) { create(:milestone, title: 'Milestone v1.0', project: project) }
+      let(:milestone) { create(:milestone, title: 'Milestone v1.0', project: project) }
 
       let(:container) { project }
 
@@ -74,8 +75,7 @@
     end
 
     context 'on group milestones' do
-      let_it_be_with_reload(:milestone) { create(:milestone, group: group) }
-
+      let(:milestone) { create(:milestone, group: group) }
       let(:container) { group }
 
       it 'deletes milestone' do
@@ -87,8 +87,6 @@
       it_behaves_like 'deletes milestone id from issuables'
 
       it 'does not log destroy event and does not run on-delete webhook' do
-        expect(service).not_to receive(:execute_hooks).with(milestone, 'delete')
-
         expect { service.execute(milestone) }.not_to change { Event.count }
       end
     end
diff --git a/spec/services/milestones/reopen_service_spec.rb b/spec/services/milestones/reopen_service_spec.rb
index fc7874cbc84fb5a74965806bc0821a6dd65faec4..2dafd66eb2e1a0d3c7199cd494fc88be4bc0cb7e 100644
--- a/spec/services/milestones/reopen_service_spec.rb
+++ b/spec/services/milestones/reopen_service_spec.rb
@@ -32,53 +32,34 @@
       end
     end
 
-    shared_examples 'reopens the milestone' do |with_project_hooks:|
-      it 'executes hooks with reopen action and creates new event' do
-        expect(service).to receive(:execute_hooks).with(milestone, 'reopen').and_call_original
-        expect(project).to receive(:execute_hooks).with(kind_of(Hash), :milestone_hooks) if with_project_hooks
-
-        expect { service.execute(milestone) }.to change { Event.count }.by(1)
-      end
-    end
-
-    shared_examples 'does not reopen the milestone' do
-      it 'does not execute hooks and does not create new event' do
-        expect(service).not_to receive(:execute_hooks)
-
-        expect { service.execute(milestone) }.not_to change { Event.count }
-      end
-    end
-
     context 'when milestone is successfully reopened' do
-      let(:milestone) { create(:milestone, :closed, project: project) }
+      context 'when milestone is a project milestone' do
+        let(:milestone) { create(:milestone, :closed, project: project) }
 
-      context 'when project has active milestone hooks' do
-        let(:project) do
-          create(:project).tap do |project|
-            create(:project_hook, project: project, milestone_events: true)
+        context 'when project has active milestone hooks' do
+          before do
+            allow(project).to receive(:has_active_hooks?).with(:milestone_hooks).and_return(true)
           end
-        end
 
-        it_behaves_like 'reopens the milestone', with_project_hooks: true
-      end
-
-      context 'when project has no active milestone hooks' do
-        it_behaves_like 'reopens the milestone', with_project_hooks: false
-      end
-    end
+          it_behaves_like 'reopens the milestone', with_hooks: true, with_event: true
+        end
 
-    context 'when milestone fails to reopen' do
-      context 'when milestone is already active' do
-        let(:milestone) { create(:milestone, project: project) }
+        context 'when project has no active milestone hooks' do
+          it_behaves_like 'reopens the milestone', with_hooks: false, with_event: true
+        end
 
-        it_behaves_like 'does not reopen the milestone'
-      end
+        context 'when milestone fails to reopen' do
+          context 'when milestone is already active' do
+            let(:milestone) { create(:milestone, project: project) }
 
-      context 'when milestone is a group milestone' do
-        let(:group) { create(:group) }
-        let(:milestone) { create(:milestone, :closed, group: group) }
+            it 'does not execute hooks and does not create new event' do
+              expect(service).not_to receive(:execute_hooks)
+              expect { service.execute(milestone) }.not_to change { Event.count }
 
-        it_behaves_like 'does not reopen the milestone'
+              expect { service.execute(milestone) }.not_to change { milestone.state }
+            end
+          end
+        end
       end
     end
   end
diff --git a/spec/support/shared_examples/services/milestones_shared_examples.rb b/spec/support/shared_examples/services/milestones_shared_examples.rb
new file mode 100644
index 0000000000000000000000000000000000000000..41403d132be7b03553ab2d02550d46d07e178682
--- /dev/null
+++ b/spec/support/shared_examples/services/milestones_shared_examples.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+RSpec.shared_examples 'creates the milestone' do |with_hooks:, with_event:|
+  it 'conditionally executes hooks with create action and creates new event' do
+    if with_hooks
+      expect(container).to receive(:execute_hooks).with(a_hash_including(action: 'create'),
+        :milestone_hooks)
+    end
+
+    expect(Event).to receive(:new).exactly(1).time.and_call_original if with_event
+
+    expect { service.execute }.to change { Milestone.count }.by(1)
+  end
+end
+
+RSpec.shared_examples 'reopens the milestone' do |with_hooks:, with_event:|
+  it 'conditionally executes hooks with reopen action and creates new event' do
+    if with_hooks
+      expect(milestone.parent).to receive(:execute_hooks).with(a_hash_including(action: 'reopen'),
+        :milestone_hooks)
+    end
+
+    expect(Event).to receive(:new).exactly(1).time.and_call_original if with_event
+
+    expect { service.execute(milestone) }.to change { milestone.state }.to('active')
+  end
+end
+
+RSpec.shared_examples 'closes the milestone' do |with_hooks:, with_event:|
+  it 'conditionally executes hooks with close action and creates new event' do
+    if with_hooks
+      expect(milestone.parent).to receive(:execute_hooks).with(a_hash_including(action: 'close'),
+        :milestone_hooks)
+    end
+
+    expect(Event).to receive(:new).exactly(1).time.and_call_original if with_event
+
+    expect { service.execute(milestone) }.to change { milestone.state }.to('closed')
+  end
+end