diff --git a/app/models/namespace.rb b/app/models/namespace.rb
index 3342fb1fce9ff7c9f51a30b1831dcce573099c37..fe7f48aba9edace794f3790c67de826740a4c010 100644
--- a/app/models/namespace.rb
+++ b/app/models/namespace.rb
@@ -84,6 +84,8 @@ class Namespace < ApplicationRecord
   before_destroy(prepend: true) { prepare_for_destroy }
   after_destroy :rm_dir
 
+  before_save :ensure_delayed_project_removal_assigned_to_namespace_settings, if: :delayed_project_removal_changed?
+
   scope :for_user, -> { where('type IS NULL') }
   scope :sort_by_type, -> { order(Gitlab::Database.nulls_first_order(:type)) }
   scope :include_route, -> { includes(:route) }
@@ -402,6 +404,13 @@ def root?
 
   private
 
+  def ensure_delayed_project_removal_assigned_to_namespace_settings
+    return if Feature.disabled?(:migrate_delayed_project_removal, default_enabled: true)
+
+    self.namespace_settings || build_namespace_settings
+    namespace_settings.delayed_project_removal = delayed_project_removal
+  end
+
   def all_projects_with_pages
     if all_projects.pages_metadata_not_migrated.exists?
       Gitlab::BackgroundMigration::MigratePagesMetadata.new.perform_on_relation(
diff --git a/app/services/groups/create_service.rb b/app/services/groups/create_service.rb
index 06a3b31c66583bf50a1f58f83dae6adc36348bb1..3ead232358886d6470c420034bb133784a1e2cf7 100644
--- a/app/services/groups/create_service.rb
+++ b/app/services/groups/create_service.rb
@@ -33,7 +33,7 @@ def execute
       Group.transaction do
         if @group.save
           @group.add_owner(current_user)
-          @group.create_namespace_settings
+          @group.create_namespace_settings unless @group.namespace_settings
           Service.create_from_active_default_integrations(@group, :group_id)
           OnboardingProgress.onboard(@group)
         end
diff --git a/changelogs/unreleased/dblessing_migrate_delayed_project_removal.yml b/changelogs/unreleased/dblessing_migrate_delayed_project_removal.yml
new file mode 100644
index 0000000000000000000000000000000000000000..c1ed2293e86155f1a04c9c07aabb86fea012de9a
--- /dev/null
+++ b/changelogs/unreleased/dblessing_migrate_delayed_project_removal.yml
@@ -0,0 +1,5 @@
+---
+title: Migrate namespaces delayed_project_removal to namespace_settings
+merge_request: 53916
+author:
+type: changed
diff --git a/config/feature_flags/development/migrate_delayed_project_removal.yml b/config/feature_flags/development/migrate_delayed_project_removal.yml
new file mode 100644
index 0000000000000000000000000000000000000000..2d4a7ef762ede1c4039d40263b219fb556ef5c3a
--- /dev/null
+++ b/config/feature_flags/development/migrate_delayed_project_removal.yml
@@ -0,0 +1,8 @@
+---
+name: migrate_delayed_project_removal
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/53916
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/300207
+milestone: '13.9'
+type: development
+group: group::access
+default_enabled: true
diff --git a/db/migrate/20210214201118_add_delayed_project_removal_to_namespace_settings.rb b/db/migrate/20210214201118_add_delayed_project_removal_to_namespace_settings.rb
new file mode 100644
index 0000000000000000000000000000000000000000..1c6e0b0c27c930e3ee99532c4b9c99e83f24cb10
--- /dev/null
+++ b/db/migrate/20210214201118_add_delayed_project_removal_to_namespace_settings.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class AddDelayedProjectRemovalToNamespaceSettings < ActiveRecord::Migration[6.0]
+  DOWNTIME = false
+
+  def change
+    add_column :namespace_settings, :delayed_project_removal, :boolean, default: false, null: false
+  end
+end
diff --git a/db/migrate/20210214205155_add_index_to_namespaces_delayed_project_removal.rb b/db/migrate/20210214205155_add_index_to_namespaces_delayed_project_removal.rb
new file mode 100644
index 0000000000000000000000000000000000000000..8d09a5c9269da268adb8643dbe03528131ff06b7
--- /dev/null
+++ b/db/migrate/20210214205155_add_index_to_namespaces_delayed_project_removal.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+class AddIndexToNamespacesDelayedProjectRemoval < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+  INDEX_NAME = 'tmp_idx_on_namespaces_delayed_project_removal'
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :namespaces, :id, name: INDEX_NAME, where: 'delayed_project_removal = TRUE'
+  end
+
+  def down
+    remove_concurrent_index_by_name :namespaces, INDEX_NAME
+  end
+end
diff --git a/db/post_migrate/20210215095328_migrate_delayed_project_removal_from_namespaces_to_namespace_settings.rb b/db/post_migrate/20210215095328_migrate_delayed_project_removal_from_namespaces_to_namespace_settings.rb
new file mode 100644
index 0000000000000000000000000000000000000000..12e156d3b8ae0907f028a922812f1999c456e7fc
--- /dev/null
+++ b/db/post_migrate/20210215095328_migrate_delayed_project_removal_from_namespaces_to_namespace_settings.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+class MigrateDelayedProjectRemovalFromNamespacesToNamespaceSettings < ActiveRecord::Migration[6.0]
+  DOWNTIME = false
+
+  class Namespace < ActiveRecord::Base
+    self.table_name = 'namespaces'
+
+    include ::EachBatch
+  end
+
+  def up
+    Namespace.select(:id).where(delayed_project_removal: true).each_batch do |batch|
+      values = batch.map { |record| "(#{record.id}, TRUE, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP)" }
+
+      execute <<-EOF.strip_heredoc
+        INSERT INTO namespace_settings (namespace_id, delayed_project_removal, created_at, updated_at)
+        VALUES #{values.join(', ')}
+        ON CONFLICT (namespace_id) DO UPDATE
+          SET delayed_project_removal = TRUE
+      EOF
+    end
+  end
+
+  def down
+    # no-op
+  end
+end
diff --git a/db/schema_migrations/20210214201118 b/db/schema_migrations/20210214201118
new file mode 100644
index 0000000000000000000000000000000000000000..9551d2ddf50c645f1b7c7a49f1bf3d89aad0cb7d
--- /dev/null
+++ b/db/schema_migrations/20210214201118
@@ -0,0 +1 @@
+8c1da1c7edba16993da93d9075ad2a3624b8c12ccf73a241e1a166014a99e254
\ No newline at end of file
diff --git a/db/schema_migrations/20210214205155 b/db/schema_migrations/20210214205155
new file mode 100644
index 0000000000000000000000000000000000000000..583d7ca1167ad6ab86a7ddf7b74b83cfca21f287
--- /dev/null
+++ b/db/schema_migrations/20210214205155
@@ -0,0 +1 @@
+7678d97de752e7a9a571d80febc74eb44c699c7b1967690d9a2391036caea5d2
\ No newline at end of file
diff --git a/db/schema_migrations/20210215095328 b/db/schema_migrations/20210215095328
new file mode 100644
index 0000000000000000000000000000000000000000..b360aaf4ad84eb1fec12a12d786c36ea28569057
--- /dev/null
+++ b/db/schema_migrations/20210215095328
@@ -0,0 +1 @@
+25820a3d060826a082565f12a3ac96deafbbde750f5756d71e34d14801ec6148
\ No newline at end of file
diff --git a/db/structure.sql b/db/structure.sql
index 5d27baaab020c99cdcf340b99466ce2cc1372ba2..83d8b59fde2053393e77b87ed7b6b392ebfa7193 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -14301,6 +14301,7 @@ CREATE TABLE namespace_settings (
     allow_mfa_for_subgroups boolean DEFAULT true NOT NULL,
     default_branch_name text,
     repository_read_only boolean DEFAULT false NOT NULL,
+    delayed_project_removal boolean DEFAULT false NOT NULL,
     CONSTRAINT check_0ba93c78c7 CHECK ((char_length(default_branch_name) <= 255))
 );
 
@@ -23760,6 +23761,8 @@ CREATE UNIQUE INDEX term_agreements_unique_index ON term_agreements USING btree
 
 CREATE INDEX tmp_idx_deduplicate_vulnerability_occurrences ON vulnerability_occurrences USING btree (project_id, report_type, location_fingerprint, primary_identifier_id, id);
 
+CREATE INDEX tmp_idx_on_namespaces_delayed_project_removal ON namespaces USING btree (id) WHERE (delayed_project_removal = true);
+
 CREATE INDEX tmp_index_on_security_findings_scan_id ON security_findings USING btree (scan_id) WHERE (uuid IS NULL);
 
 CREATE INDEX tmp_index_on_vulnerabilities_non_dismissed ON vulnerabilities USING btree (id) WHERE (state <> 2);
diff --git a/spec/factories/groups.rb b/spec/factories/groups.rb
index 17db69e4699bdb4c81746ac8360a8902ad885ffd..065eb36375a33bf1d70cf2ceea903dd65f8460eb 100644
--- a/spec/factories/groups.rb
+++ b/spec/factories/groups.rb
@@ -15,7 +15,7 @@
         raise "Don't set owner for groups, use `group.add_owner(user)` instead"
       end
 
-      create(:namespace_settings, namespace: group)
+      create(:namespace_settings, namespace: group) unless group.namespace_settings
     end
 
     trait :public do
diff --git a/spec/migrations/migrate_delayed_project_removal_from_namespaces_to_namespace_settings_spec.rb b/spec/migrations/migrate_delayed_project_removal_from_namespaces_to_namespace_settings_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..28a8dcf0d4cbc901aa6b82520aca3b9bbe778ce4
--- /dev/null
+++ b/spec/migrations/migrate_delayed_project_removal_from_namespaces_to_namespace_settings_spec.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+require Rails.root.join('db', 'post_migrate', '20210215095328_migrate_delayed_project_removal_from_namespaces_to_namespace_settings.rb')
+
+RSpec.describe MigrateDelayedProjectRemovalFromNamespacesToNamespaceSettings, :migration do
+  let(:namespaces) { table(:namespaces) }
+  let(:namespace_settings) { table(:namespace_settings) }
+
+  let!(:namespace_wo_settings) { namespaces.create!(name: generate(:name), path: generate(:name), delayed_project_removal: true) }
+  let!(:namespace_wo_settings_delay_false) { namespaces.create!(name: generate(:name), path: generate(:name), delayed_project_removal: false) }
+  let!(:namespace_w_settings_delay_true) { namespaces.create!(name: generate(:name), path: generate(:name), delayed_project_removal: true) }
+  let!(:namespace_w_settings_delay_false) { namespaces.create!(name: generate(:name), path: generate(:name), delayed_project_removal: false) }
+
+  let!(:namespace_settings_delay_true) { namespace_settings.create!(namespace_id: namespace_w_settings_delay_true.id, delayed_project_removal: false, created_at: DateTime.now, updated_at: DateTime.now) }
+  let!(:namespace_settings_delay_false) { namespace_settings.create!(namespace_id: namespace_w_settings_delay_false.id, delayed_project_removal: false, created_at: DateTime.now, updated_at: DateTime.now) }
+
+  it 'migrates delayed_project_removal to namespace_settings' do
+    disable_migrations_output { migrate! }
+
+    expect(namespace_settings.count).to eq(3)
+
+    expect(namespace_settings.find_by(namespace_id: namespace_wo_settings.id).delayed_project_removal).to eq(true)
+    expect(namespace_settings.find_by(namespace_id: namespace_wo_settings_delay_false.id)).to be_nil
+
+    expect(namespace_settings_delay_true.reload.delayed_project_removal).to eq(true)
+    expect(namespace_settings_delay_false.reload.delayed_project_removal).to eq(false)
+  end
+end
diff --git a/spec/models/namespace_spec.rb b/spec/models/namespace_spec.rb
index 647e279bf8391c3620583442445080a404c28b0b..c36443828b5fedd81d9bd7e58bc4f3443aaf05ef 100644
--- a/spec/models/namespace_spec.rb
+++ b/spec/models/namespace_spec.rb
@@ -6,7 +6,7 @@
   include ProjectForksHelper
   include GitHelpers
 
-  let!(:namespace) { create(:namespace) }
+  let!(:namespace) { create(:namespace, :with_namespace_settings) }
   let(:gitlab_shell) { Gitlab::Shell.new }
   let(:repository_storage) { 'default' }
 
@@ -116,6 +116,28 @@
     it { is_expected.to include_module(Namespaces::Traversal::Recursive) }
   end
 
+  describe 'callbacks' do
+    describe 'before_save :ensure_delayed_project_removal_assigned_to_namespace_settings' do
+      it 'sets the matching value in namespace_settings' do
+        expect { namespace.update!(delayed_project_removal: true) }.to change {
+          namespace.namespace_settings.delayed_project_removal
+        }.from(false).to(true)
+      end
+
+      context 'when the feature flag is disabled' do
+        before do
+          stub_feature_flags(migrate_delayed_project_removal: false)
+        end
+
+        it 'does not set the matching value in namespace_settings' do
+          expect { namespace.update!(delayed_project_removal: true) }.not_to change {
+            namespace.namespace_settings.delayed_project_removal
+          }
+        end
+      end
+    end
+  end
+
   describe '#visibility_level_field' do
     it { expect(namespace.visibility_level_field).to eq(:visibility_level) }
   end