diff --git a/app/notifications/validators.py b/app/notifications/validators.py
index fe9f336a7..181d48b6e 100644
--- a/app/notifications/validators.py
+++ b/app/notifications/validators.py
@@ -138,7 +138,7 @@ def validate_template(template_id, personalisation, service, notification_type):
 def check_service_email_reply_to_id(service_id, reply_to_id):
     if not (reply_to_id is None):
         try:
-            reply_to = dao_get_reply_to_by_id(service_id, reply_to_id)
+            dao_get_reply_to_by_id(service_id, reply_to_id)
         except NoResultFound:
             message = 'email_reply_to_id {} does not exist in database for service id {}'\
                 .format(reply_to_id, service_id)
diff --git a/app/service/send_notification.py b/app/service/send_notification.py
index 1ca19661c..d1ed9a5a3 100644
--- a/app/service/send_notification.py
+++ b/app/service/send_notification.py
@@ -3,17 +3,17 @@ from app.notifications.validators import (
     check_service_over_daily_message_limit,
     validate_and_format_recipient,
     validate_template,
-)
+    check_service_email_reply_to_id)
 from app.notifications.process_notifications import (
     create_content_for_notification,
     persist_notification,
     send_notification_to_queue,
-)
+    persist_email_reply_to_id_for_notification)
 from app.models import (
     KEY_TYPE_NORMAL,
     PRIORITY,
     SMS_TYPE,
-)
+    EMAIL_TYPE)
 from app.dao.services_dao import dao_fetch_service_by_id
 from app.dao.templates_dao import dao_get_template_by_id_and_service_id
 from app.dao.users_dao import get_user_by_id
@@ -63,6 +63,10 @@ def send_one_off_notification(service_id, post_data):
         key_type=KEY_TYPE_NORMAL,
         created_by_id=post_data['created_by']
     )
+    sender_id = post_data.get('sender_id', None)
+    if sender_id and template.template_type == EMAIL_TYPE:
+        check_service_email_reply_to_id(service_id, sender_id)
+        persist_email_reply_to_id_for_notification(notification.id, sender_id)
 
     queue_name = QueueNames.PRIORITY if template.process_type == PRIORITY else None
     send_notification_to_queue(
diff --git a/tests/app/service/test_send_one_off_notification.py b/tests/app/service/test_send_one_off_notification.py
index 89ddcd91a..1fe9dc155 100644
--- a/tests/app/service/test_send_one_off_notification.py
+++ b/tests/app/service/test_send_one_off_notification.py
@@ -7,9 +7,14 @@ from notifications_utils.recipients import InvalidPhoneError
 from app.v2.errors import BadRequestError, TooManyRequestsError
 from app.config import QueueNames
 from app.service.send_notification import send_one_off_notification
-from app.models import KEY_TYPE_NORMAL, PRIORITY, SMS_TYPE
+from app.models import (
+    KEY_TYPE_NORMAL,
+    PRIORITY,
+    SMS_TYPE,
+    NotificationEmailReplyTo,
+    Notification)
 
-from tests.app.db import create_user
+from tests.app.db import create_user, create_reply_to_email
 
 
 @pytest.fixture
@@ -178,3 +183,37 @@ def test_send_one_off_notification_fails_if_created_by_other_service(sample_temp
         send_one_off_notification(sample_template.service_id, post_data)
 
     assert e.value.message == 'Can’t create notification - Test User is not part of the "Sample service" service'
+
+
+def test_send_one_off_notification_should_add_email_reply_to_id_for_email(sample_email_template, celery_mock):
+    reply_to_email = create_reply_to_email(sample_email_template.service, 'test@test.com')
+    data = {
+        'to': 'ok@ok.com',
+        'template_id': str(sample_email_template.id),
+        'sender_id': reply_to_email.id,
+        'created_by': str(sample_email_template.service.created_by_id)
+    }
+
+    notification_id = send_one_off_notification(service_id=sample_email_template.service.id, post_data=data)
+    notification = Notification.query.get(notification_id['id'])
+    celery_mock.assert_called_once_with(
+        notification=notification,
+        research_mode=False,
+        queue=None
+    )
+    mapping_row = NotificationEmailReplyTo.query.filter_by(notification_id=notification_id['id']).first()
+    assert mapping_row.service_email_reply_to_id == reply_to_email.id
+
+
+def test_send_one_off_notification_should_throw_exception_if_reply_to_id_doesnot_exist(
+        sample_email_template, celery_mock
+):
+    data = {
+        'to': 'ok@ok.com',
+        'template_id': str(sample_email_template.id),
+        'sender_id': str(uuid.uuid4()),
+        'created_by': str(sample_email_template.service.created_by_id)
+    }
+
+    with pytest.raises(expected_exception=BadRequestError):
+        send_one_off_notification(service_id=sample_email_template.service.id, post_data=data)