diff --git a/app/dao/notifications_dao.py b/app/dao/notifications_dao.py
index fef7b9567..55665a642 100644
--- a/app/dao/notifications_dao.py
+++ b/app/dao/notifications_dao.py
@@ -40,7 +40,7 @@ from app.models import (
     KEY_TYPE_NORMAL, KEY_TYPE_TEST,
     LETTER_TYPE,
     NOTIFICATION_SENT,
-)
+    NotificationEmailReplyTo, ServiceEmailReplyTo)
 
 from app.dao.dao_utils import transactional
 from app.statsd_decorators import statsd
@@ -603,3 +603,23 @@ def dao_set_created_live_letter_api_notifications_to_pending():
     db.session.commit()
 
     return notifications
+
+
+@transactional
+def dao_create_notification_email_reply_to_mapping(notification_id, email_reply_to_id):
+    notification_email_reply_to = NotificationEmailReplyTo(
+        notification_id=notification_id,
+        service_email_reply_to_id=email_reply_to_id
+    )
+    db.session.add(notification_email_reply_to)
+
+
+def dao_get_notification_email_reply_for_notification(notification_id):
+    email_reply_to = ServiceEmailReplyTo.query.join(
+        NotificationEmailReplyTo
+    ).filter(
+        NotificationEmailReplyTo.notification_id == notification_id
+    ).all()
+
+    if len(email_reply_to) == 1:
+        return email_reply_to[0].email_address
diff --git a/app/notifications/process_notifications.py b/app/notifications/process_notifications.py
index 8a75473b4..2b8992ba1 100644
--- a/app/notifications/process_notifications.py
+++ b/app/notifications/process_notifications.py
@@ -16,7 +16,8 @@ from app.config import QueueNames
 from app.models import SMS_TYPE, Notification, KEY_TYPE_TEST, EMAIL_TYPE, NOTIFICATION_CREATED, ScheduledNotification
 from app.dao.notifications_dao import (dao_create_notification,
                                        dao_delete_notifications_and_history_by_id,
-                                       dao_created_scheduled_notification)
+                                       dao_created_scheduled_notification,
+                                       dao_create_notification_email_reply_to_mapping)
 from app.v2.errors import BadRequestError
 from app.utils import get_template_instance, cache_key_for_service_template_counter, convert_bst_to_utc
 
@@ -141,3 +142,7 @@ def persist_scheduled_notification(notification_id, scheduled_for):
     scheduled_notification = ScheduledNotification(notification_id=notification_id,
                                                    scheduled_for=scheduled_datetime)
     dao_created_scheduled_notification(scheduled_notification)
+
+
+def persist_email_reply_to_id_for_notification(notification_id, email_reply_to_id):
+    dao_create_notification_email_reply_to_mapping(notification_id, email_reply_to_id)
diff --git a/app/v2/notifications/post_notifications.py b/app/v2/notifications/post_notifications.py
index 04c63a3e7..9e22e2346 100644
--- a/app/v2/notifications/post_notifications.py
+++ b/app/v2/notifications/post_notifications.py
@@ -19,7 +19,7 @@ from app.notifications.process_notifications import (
     persist_notification,
     send_notification_to_queue,
     simulated_recipient,
-    persist_scheduled_notification)
+    persist_scheduled_notification, persist_email_reply_to_id_for_notification)
 from app.notifications.process_letter_notifications import (
     create_letter_notification
 )
@@ -140,6 +140,10 @@ def process_sms_or_email_notification(*, form, notification_type, api_key, templ
         simulated=simulated
     )
 
+    email_reply_to_id = form.get("email_reply_to_id", None)
+    if email_reply_to_id is not None:
+        persist_email_reply_to_id_for_notification(notification.id, email_reply_to_id)
+
     scheduled_for = form.get("scheduled_for", None)
     if scheduled_for:
         persist_scheduled_notification(notification.id, form["scheduled_for"])
diff --git a/tests/app/dao/notification_dao/test_notification_dao.py b/tests/app/dao/notification_dao/test_notification_dao.py
index ba8378827..901eeb783 100644
--- a/tests/app/dao/notification_dao/test_notification_dao.py
+++ b/tests/app/dao/notification_dao/test_notification_dao.py
@@ -6,6 +6,7 @@ import pytest
 from freezegun import freeze_time
 from sqlalchemy.exc import SQLAlchemyError, IntegrityError
 
+from app.dao.service_email_reply_to_dao import dao_get_reply_to_by_service_id
 from app.models import (
     Notification,
     NotificationHistory,
@@ -18,8 +19,8 @@ from app.models import (
     NOTIFICATION_DELIVERED,
     KEY_TYPE_NORMAL,
     KEY_TYPE_TEAM,
-    KEY_TYPE_TEST
-)
+    KEY_TYPE_TEST,
+    NotificationEmailReplyTo)
 
 from app.dao.notifications_dao import (
     dao_create_notification,
@@ -44,11 +45,11 @@ from app.dao.notifications_dao import (
     dao_get_notifications_by_to_field,
     dao_created_scheduled_notification,
     dao_get_scheduled_notifications,
-    set_scheduled_notification_to_processed
-)
+    set_scheduled_notification_to_processed,
+    dao_create_notification_email_reply_to_mapping, dao_get_notification_email_reply_for_notification)
 
 from app.dao.services_dao import dao_update_service
-from tests.app.db import create_notification, create_api_key
+from tests.app.db import create_notification, create_api_key, create_reply_to_email
 from tests.app.conftest import (
     sample_notification,
     sample_template,
@@ -1949,3 +1950,49 @@ def test_dao_get_notifications_by_to_field_orders_by_created_at_desc(sample_temp
     assert len(notifications) == 2
     assert notifications[0].id == notification.id
     assert notifications[1].id == notification_a_minute_ago.id
+
+
+def test_dao_create_notification_email_reply_to_mapping(sample_service, sample_notification):
+
+    create_reply_to_email(sample_service, "test@test.com")
+
+    reply_to_address = dao_get_reply_to_by_service_id(sample_service.id)
+
+    dao_create_notification_email_reply_to_mapping(sample_notification.id, reply_to_address[0].id)
+
+    email_reply_to = NotificationEmailReplyTo.query.all()
+
+    assert len(email_reply_to) == 1
+    assert email_reply_to[0].notification_id == sample_notification.id
+    assert email_reply_to[0].service_email_reply_to_id == reply_to_address[0].id
+
+
+def test_dao_create_multiple_notification_email_reply_to_mapping(sample_service, sample_notification):
+
+    create_reply_to_email(sample_service, "test@test.com")
+
+    reply_to_address = dao_get_reply_to_by_service_id(sample_service.id)
+
+    dao_create_notification_email_reply_to_mapping(sample_notification.id, reply_to_address[0].id)
+
+    with pytest.raises(IntegrityError) as e:
+        dao_create_notification_email_reply_to_mapping(sample_notification.id, reply_to_address[0].id)
+
+    assert 'duplicate key value' in str(e.value)
+
+    email_reply_to = NotificationEmailReplyTo.query.all()
+
+    assert len(email_reply_to) == 1
+    assert email_reply_to[0].notification_id == sample_notification.id
+    assert email_reply_to[0].service_email_reply_to_id == reply_to_address[0].id
+
+
+def test_dao_get_notification_email_reply_for_notification(sample_service, sample_notification):
+    create_reply_to_email(sample_service, "test@test.com")
+    reply_to_address = dao_get_reply_to_by_service_id(sample_service.id)
+    dao_create_notification_email_reply_to_mapping(sample_notification.id, reply_to_address[0].id)
+    assert dao_get_notification_email_reply_for_notification(sample_notification.id) == "test@test.com"
+
+
+def test_dao_get_notification_email_reply_for_notification_where_no_mapping(fake_uuid):
+    assert dao_get_notification_email_reply_for_notification(fake_uuid) is None
diff --git a/tests/app/notifications/test_process_notification.py b/tests/app/notifications/test_process_notification.py
index fbe9787c6..e8e67568b 100644
--- a/tests/app/notifications/test_process_notification.py
+++ b/tests/app/notifications/test_process_notification.py
@@ -7,18 +7,20 @@ from sqlalchemy.exc import SQLAlchemyError
 from freezegun import freeze_time
 from collections import namedtuple
 
-from app.models import Template, Notification, NotificationHistory, ScheduledNotification
+from app.dao.service_email_reply_to_dao import dao_get_reply_to_by_service_id
+from app.models import Template, Notification, NotificationHistory, ScheduledNotification, NotificationEmailReplyTo
 from app.notifications.process_notifications import (
     create_content_for_notification,
     persist_notification,
     send_notification_to_queue,
     simulated_recipient,
-    persist_scheduled_notification
-)
+    persist_scheduled_notification,
+    persist_email_reply_to_id_for_notification)
 from notifications_utils.recipients import validate_and_format_phone_number, validate_and_format_email_address
 from app.utils import cache_key_for_service_template_counter
 from app.v2.errors import BadRequestError
 from tests.app.conftest import sample_api_key as create_api_key
+from tests.app.db import create_reply_to_email
 
 
 def test_create_content_for_notification_passes(sample_email_template):
@@ -438,3 +440,15 @@ def test_persist_email_notification_stores_normalised_email(
 
     assert persisted_notification.to == recipient
     assert persisted_notification.normalised_to == expected_recipient_normalised
+
+
+def test_persist_email_reply_to_id_for_notification(sample_service, sample_notification):
+    create_reply_to_email(sample_service, "test@test.com")
+    reply_to_address = dao_get_reply_to_by_service_id(sample_service.id)
+    persist_email_reply_to_id_for_notification(sample_notification.id, reply_to_address[0].id)
+
+    email_reply_to = NotificationEmailReplyTo.query.all()
+
+    assert len(email_reply_to) == 1
+    assert email_reply_to[0].notification_id == sample_notification.id
+    assert email_reply_to[0].service_email_reply_to_id == reply_to_address[0].id
diff --git a/tests/app/notifications/test_validators.py b/tests/app/notifications/test_validators.py
index 66779b70e..b59decc9f 100644
--- a/tests/app/notifications/test_validators.py
+++ b/tests/app/notifications/test_validators.py
@@ -347,3 +347,26 @@ def test_check_service_email_reply_to_id_where_service_id_is_not_found(sample_se
         check_service_email_reply_to_id(fake_uuid, fake_uuid)
     assert e.value.status_code == 400
     assert e.value.message == 'email_reply_to_id does not exist in database'
+
+
+def test_check_service_email_reply_to_id_where_reply_to_id_is_none():
+    assert check_service_email_reply_to_id(None, None) is None
+
+
+def test_check_service_email_reply_to_id_where_reply_to_id_is_not_found(sample_service, fake_uuid):
+    with pytest.raises(BadRequestError) as e:
+        check_service_email_reply_to_id(sample_service.id, fake_uuid)
+    assert e.value.status_code == 400
+    assert e.value.message == 'email_reply_to_id does not exist in database'
+
+
+def test_check_service_email_reply_to_id_where_reply_to_id_is_found(sample_service):
+    reply_to_email = create_reply_to_email(sample_service, 'test@test.com')
+    assert check_service_email_reply_to_id(sample_service.id, reply_to_email.id) is None
+
+
+def test_check_service_email_reply_to_id_where_service_id_is_not_found(sample_service, fake_uuid):
+    with pytest.raises(BadRequestError) as e:
+        check_service_email_reply_to_id(fake_uuid, fake_uuid)
+    assert e.value.status_code == 400
+    assert e.value.message == 'email_reply_to_id does not exist in database'
diff --git a/tests/app/v2/notifications/test_post_notifications.py b/tests/app/v2/notifications/test_post_notifications.py
index d4fdf94ec..1f0c8091d 100644
--- a/tests/app/v2/notifications/test_post_notifications.py
+++ b/tests/app/v2/notifications/test_post_notifications.py
@@ -5,8 +5,8 @@ from freezegun import freeze_time
 
 from app.models import (
     Notification, ScheduledNotification, SCHEDULE_NOTIFICATIONS,
-    EMAIL_TYPE, INTERNATIONAL_SMS_TYPE, SMS_TYPE
-)
+    EMAIL_TYPE, INTERNATIONAL_SMS_TYPE, SMS_TYPE,
+    NotificationEmailReplyTo)
 from flask import json, current_app
 
 from app.models import Notification
@@ -524,3 +524,48 @@ def test_post_email_notification_with_valid_reply_to_id_returns_201(client, samp
     notification = Notification.query.first()
     assert resp_json['id'] == str(notification.id)
     assert mocked.called
+
+
+def test_post_email_notification_with_invalid_reply_to_id_returns_400(client, sample_email_template, mocker, fake_uuid):
+    mocked = mocker.patch('app.celery.provider_tasks.deliver_email.apply_async')
+    data = {
+        "email_address": sample_email_template.service.users[0].email_address,
+        "template_id": sample_email_template.id,
+        'email_reply_to_id': fake_uuid
+    }
+    auth_header = create_authorization_header(service_id=sample_email_template.service_id)
+    response = client.post(
+        path="v2/notifications/email",
+        data=json.dumps(data),
+        headers=[('Content-Type', 'application/json'), auth_header])
+    assert response.status_code == 400
+    resp_json = json.loads(response.get_data(as_text=True))
+    assert 'reply_to_id does not exist in database' in resp_json['errors'][0]['message']
+    assert 'BadRequestError' in resp_json['errors'][0]['error']
+
+
+def test_post_email_notification_with_valid_reply_to_id_returns_201(client, sample_email_template, mocker):
+    reply_to_email = create_reply_to_email(sample_email_template.service, 'test@test.com')
+    mocked = mocker.patch('app.celery.provider_tasks.deliver_email.apply_async')
+    data = {
+        "email_address": sample_email_template.service.users[0].email_address,
+        "template_id": sample_email_template.id,
+        'email_reply_to_id': reply_to_email.id
+    }
+    auth_header = create_authorization_header(service_id=sample_email_template.service_id)
+    response = client.post(
+        path="v2/notifications/email",
+        data=json.dumps(data),
+        headers=[('Content-Type', 'application/json'), auth_header])
+    assert response.status_code == 201
+    resp_json = json.loads(response.get_data(as_text=True))
+    assert validate(resp_json, post_email_response) == resp_json
+    notification = Notification.query.first()
+    assert resp_json['id'] == str(notification.id)
+    assert mocked.called
+
+    email_reply_to = NotificationEmailReplyTo.query.all()
+
+    assert len(email_reply_to) == 1
+    assert email_reply_to[0].notification_id == notification.id
+    assert email_reply_to[0].service_email_reply_to_id == reply_to_email.id