diff --git a/app/dao/notifications_dao.py b/app/dao/notifications_dao.py
index aa57779f7..b3c698d71 100644
--- a/app/dao/notifications_dao.py
+++ b/app/dao/notifications_dao.py
@@ -43,6 +43,7 @@ from app.models import (
     NOTIFICATION_TEMPORARY_FAILURE,
     NOTIFICATION_PERMANENT_FAILURE,
     NOTIFICATION_SENT,
+    NOTIFICATION_STATUS_TYPES_COMPLETED,
     SMS_TYPE,
     EMAIL_TYPE,
     ServiceDataRetention,
@@ -428,8 +429,10 @@ def _delete_letters_from_s3(
     ).limit(query_limit).all()
     for letter in letters_to_delete_from_s3:
         bucket_name = current_app.config['LETTERS_PDF_BUCKET_NAME']
-        # I don't think we need this anymore, we should update the query to get letters sent 7 days ago
-        if letter.sent_at:
+        # We don't want to delete PDFs for letters until they have transitioned past created and sending, as at that
+        # point we are confident that our print provider could successfully handle them and there is no chance of us
+        # needing to resend them
+        if letter.status in NOTIFICATION_STATUS_TYPES_COMPLETED:
             prefix = get_letter_pdf_filename(reference=letter.reference,
                                              crown=letter.service.crown,
                                              created_at=letter.created_at,
diff --git a/tests/app/dao/notification_dao/test_notification_dao_delete_notifications.py b/tests/app/dao/notification_dao/test_notification_dao_delete_notifications.py
index 8d4a2fb71..bda92114d 100644
--- a/tests/app/dao/notification_dao/test_notification_dao_delete_notifications.py
+++ b/tests/app/dao/notification_dao/test_notification_dao_delete_notifications.py
@@ -133,12 +133,17 @@ def test_delete_notifications_for_days_of_retention(sample_service, notification
 
 
 @freeze_time('2019-09-01 04:30')
-def test_delete_notifications_deletes_letters_from_s3(sample_letter_template, mocker):
+@pytest.mark.parametrize('notification_status', ['delivered', 'returned-letter', 'technical-failure'])
+def test_delete_notifications_deletes_letters_from_s3(sample_letter_template, mocker, notification_status):
     mock_get_s3 = mocker.patch("app.dao.notifications_dao.get_s3_bucket_objects")
     eight_days_ago = datetime.utcnow() - timedelta(days=8)
-    create_notification(template=sample_letter_template, status='delivered',
-                        reference='LETTER_REF', created_at=eight_days_ago, sent_at=eight_days_ago
-                        )
+    create_notification(
+        template=sample_letter_template,
+        status=notification_status,
+        reference='LETTER_REF',
+        created_at=eight_days_ago,
+        sent_at=eight_days_ago
+    )
     delete_notifications_older_than_retention_by_type(notification_type='letter')
     mock_get_s3.assert_called_once_with(bucket_name=current_app.config['LETTERS_PDF_BUCKET_NAME'],
                                         subfolder="{}/NOTIFY.LETTER_REF.D.2.C.C.{}.PDF".format(
@@ -212,13 +217,16 @@ def test_delete_notifications_delete_notification_type_for_default_time_if_no_da
     assert Notification.query.filter_by(notification_type='email').count() == 1
 
 
-def test_delete_notifications_doesnt_try_to_delete_from_s3_when_letter_has_not_sent(sample_service, mocker):
+@pytest.mark.parametrize('notification_status', ['created', 'sending'])
+def test_delete_notifications_doesnt_try_to_delete_from_s3_when_letter_has_not_finished_sending(
+    sample_service, mocker, notification_status
+):
     mock_get_s3 = mocker.patch("app.dao.notifications_dao.get_s3_bucket_objects")
     letter_template = create_template(service=sample_service, template_type='letter')
 
     create_notification(
         template=letter_template,
-        status='created',
+        status=notification_status,
         reference='LETTER_REF',
         created_at=datetime.utcnow() - timedelta(days=14)
     )