diff --git a/app/main/views/notifications.py b/app/main/views/notifications.py
index 2a533bc30..00199291b 100644
--- a/app/main/views/notifications.py
+++ b/app/main/views/notifications.py
@@ -95,6 +95,8 @@ def view_notification(service_id, notification_id):
         page_count=page_count,
         show_recipient=True,
         redact_missing_personalisation=True,
+        sms_sender=notification['reply_to_text'],
+        email_reply_to=notification['reply_to_text'],
     )
     template.values = personalisation
     if notification['job']:
diff --git a/app/main/views/send.py b/app/main/views/send.py
index 20d1deddc..04356069e 100644
--- a/app/main/views/send.py
+++ b/app/main/views/send.py
@@ -218,6 +218,10 @@ def set_sender(service_id, template_id):
         return redirect_to_one_off
 
     sender_details = get_sender_details(service_id, template['template_type'])
+
+    if len(sender_details) == 1:
+        session['sender_id'] = sender_details[0]['id']
+
     if len(sender_details) <= 1:
         return redirect_to_one_off
 
diff --git a/tests/app/main/views/test_notifications.py b/tests/app/main/views/test_notifications.py
index 3160c4cff..0a44ee326 100644
--- a/tests/app/main/views/test_notifications.py
+++ b/tests/app/main/views/test_notifications.py
@@ -949,3 +949,22 @@ def test_cancelling_a_letter_calls_the_api(
     )
 
     assert cancel_endpoint.called
+
+
+@pytest.mark.parametrize('notification_type', ['sms', 'email'])
+def test_should_show_reply_to_from_notification(
+    mocker,
+    fake_uuid,
+    notification_type,
+    client_request,
+):
+    notification = create_notification(reply_to_text='reply to info', template_type=notification_type)
+    mocker.patch('app.notification_api_client.get_notification', return_value=notification)
+
+    page = client_request.get(
+        'main.view_notification',
+        service_id=SERVICE_ONE_ID,
+        notification_id=fake_uuid,
+    )
+
+    assert 'reply to info' in page.text
diff --git a/tests/app/main/views/test_send.py b/tests/app/main/views/test_send.py
index 8fe90dce6..06a7c8c56 100644
--- a/tests/app/main/views/test_send.py
+++ b/tests/app/main/views/test_send.py
@@ -254,6 +254,52 @@ def test_set_sender_redirects_if_no_sms_senders(
     )
 
 
+def test_set_sender_redirects_if_one_email_sender(
+    client_request,
+    fake_uuid,
+    mock_get_service_email_template,
+    single_reply_to_email_address,
+):
+    client_request.get(
+        '.set_sender',
+        service_id=SERVICE_ONE_ID,
+        template_id=fake_uuid,
+        _expected_status=302,
+        _expected_url=url_for(
+            '.send_one_off',
+            service_id=SERVICE_ONE_ID,
+            template_id=fake_uuid,
+            _external=True,
+        )
+    )
+
+    with client_request.session_transaction() as session:
+        assert session['sender_id'] == '1234'
+
+
+def test_set_sender_redirects_if_one_sms_sender(
+    client_request,
+    fake_uuid,
+    mock_get_service_template,
+    single_sms_sender,
+):
+    client_request.get(
+        '.set_sender',
+        service_id=SERVICE_ONE_ID,
+        template_id=fake_uuid,
+        _expected_status=302,
+        _expected_url=url_for(
+            '.send_one_off',
+            service_id=SERVICE_ONE_ID,
+            template_id=fake_uuid,
+            _external=True,
+        )
+    )
+
+    with client_request.session_transaction() as session:
+        assert session['sender_id'] == '1234'
+
+
 def test_that_test_files_exist():
     assert len(test_spreadsheet_files) == 8
     assert len(test_non_spreadsheet_files) == 6
diff --git a/tests/conftest.py b/tests/conftest.py
index e1d8eee1d..98e2a551e 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -4174,13 +4174,15 @@ def create_notification(
     key_type=None,
     postage=None,
     sent_one_off=True,
+    reply_to_text=None,
 ):
     noti = notification_json(
         service_id,
         rows=1,
         status=notification_status,
         template_type=template_type,
-        postage=postage
+        postage=postage,
+        reply_to_text=reply_to_text,
     )['notifications'][0]
 
     noti['id'] = notifification_id or sample_uuid()