diff --git a/lib/tasks/data_migrations/regenerate_registrar_reference_numbers.rake b/lib/tasks/data_migrations/regenerate_registrar_reference_numbers.rake
index aff296d83..6f6aaebe2 100644
--- a/lib/tasks/data_migrations/regenerate_registrar_reference_numbers.rake
+++ b/lib/tasks/data_migrations/regenerate_registrar_reference_numbers.rake
@@ -6,9 +6,7 @@ namespace :data_migrations do
       Registrar.all.each do |registrar|
         next unless registrar.reference_no.start_with?('RF')
 
-        registrar.reference_no = Billing::ReferenceNo.generate
-        registrar.save!
-
+        registrar.update_columns(reference_no: Billing::ReferenceNo.generate)
         processed_registrar_count += 1
       end
     end
diff --git a/test/fixtures/registrars.yml b/test/fixtures/registrars.yml
index e2d6dfc13..be7adaa5b 100644
--- a/test/fixtures/registrars.yml
+++ b/test/fixtures/registrars.yml
@@ -35,3 +35,14 @@ not_in_use:
   accounting_customer_code: any
   language: en
   reference_no: 39
+
+invalid:
+  name: ""
+  reg_no: any
+  code: another
+  email: any
+  country_code: US
+  vat_no: any
+  accounting_customer_code: any
+  language: en
+  reference_no: 42
diff --git a/test/integration/tasks/data_migrations/regenerate_registrar_reference_numbers_test.rb b/test/integration/tasks/data_migrations/regenerate_registrar_reference_numbers_test.rb
index 7700b3fb6..c496cd95b 100644
--- a/test/integration/tasks/data_migrations/regenerate_registrar_reference_numbers_test.rb
+++ b/test/integration/tasks/data_migrations/regenerate_registrar_reference_numbers_test.rb
@@ -11,6 +11,17 @@ class RegenerateRegistrarReferenceNumbersTaskTest < ActiveSupport::TestCase
     assert_not registrar.reference_no.start_with?('RF')
   end
 
+  def test_bypasses_registrar_validation
+    registrar = registrars(:invalid)
+    registrar.update_column(:reference_no, 'RF1111')
+    assert registrar.invalid?
+
+    capture_io { run_task }
+    registrar.reload
+
+    assert_not registrar.reference_no.start_with?('RF')
+  end
+
   def test_does_not_regenerate_when_the_task_is_run_again
     registrar = registrars(:bestnames)
     registrar.update!(reference_no: '1111')
diff --git a/test/models/registrar_test.rb b/test/models/registrar_test.rb
index bc50e4071..242e19c89 100644
--- a/test/models/registrar_test.rb
+++ b/test/models/registrar_test.rb
@@ -5,10 +5,14 @@ class RegistrarTest < ActiveSupport::TestCase
     @registrar = registrars(:bestnames)
   end
 
-  def test_valid
+  def test_default_fixture_is_valid
     assert @registrar.valid?, proc { @registrar.errors.full_messages }
   end
 
+  def test_invalid_fixture_is_invalid
+    assert registrars(:invalid).invalid?
+  end
+
   def test_invalid_without_name
     @registrar.name = ''
     assert @registrar.invalid?