diff --git a/app/template/rest.py b/app/template/rest.py
index 5f36557e0..e49eea762 100644
--- a/app/template/rest.py
+++ b/app/template/rest.py
@@ -7,7 +7,6 @@ from flask import (
     jsonify,
     request)
 from requests import post as requests_post
-from werkzeug.exceptions import abort
 
 
 from app.dao.notifications_dao import get_notification_by_id
@@ -207,7 +206,9 @@ def preview_letter_template_by_notification_id(service_id, notification_id, file
             pdf_file = get_letter_pdf(notification)
 
         except botocore.exceptions.ClientError:
-            abort(404)
+            current_app.logger.info
+            raise InvalidRequest('Error getting letter file from S3 notification id {}'.format(notification_id),
+                                 status_code=500)
 
         content = base64.b64encode(pdf_file).decode('utf-8')
 
@@ -218,18 +219,7 @@ def preview_letter_template_by_notification_id(service_id, notification_id, file
                 '?page={}'.format(page) if page else ''
             )
 
-            resp = requests_post(
-                url,
-                data=content,
-                headers={'Authorization': 'Token {}'.format(current_app.config['TEMPLATE_PREVIEW_API_KEY'])}
-            )
-
-            if resp.status_code != 200:
-                raise InvalidRequest(
-                    'Error generating preview for {}'.format(notification_id), status_code=500
-                )
-
-            content = base64.b64encode(resp.content).decode('utf-8')
+            content = _get_png_preview(url, content, notification.id)
 
     else:
 
@@ -249,21 +239,27 @@ def preview_letter_template_by_notification_id(service_id, notification_id, file
             'dvla_org_id': service.dvla_organisation_id,
         }
 
-        resp = requests_post(
-            '{}/preview.{}{}'.format(
-                current_app.config['TEMPLATE_PREVIEW_API_HOST'],
-                file_type,
-                '?page={}'.format(page) if page else ''
-            ),
-            json=data,
-            headers={'Authorization': 'Token {}'.format(current_app.config['TEMPLATE_PREVIEW_API_KEY'])}
+        url = '{}/preview.{}{}'.format(
+            current_app.config['TEMPLATE_PREVIEW_API_HOST'],
+            file_type,
+            '?page={}'.format(page) if page else ''
         )
 
-        if resp.status_code != 200:
-            raise InvalidRequest(
-                'Error generating preview for {}'.format(notification_id), status_code=500
-            )
-
-        content = base64.b64encode(resp.content).decode('utf-8')
+        content = _get_png_preview(url, data, notification.id)
 
     return jsonify({"content": content})
+
+
+def _get_png_preview(url, data, notification_id):
+    resp = requests_post(
+        url,
+        data=data,
+        headers={'Authorization': 'Token {}'.format(current_app.config['TEMPLATE_PREVIEW_API_KEY'])}
+    )
+
+    if resp.status_code != 200:
+        raise InvalidRequest(
+            'Error generating preview for {}'.format(notification_id), status_code=500
+        )
+
+    return base64.b64encode(resp.content).decode('utf-8')
diff --git a/tests/app/template/test_rest.py b/tests/app/template/test_rest.py
index 34192148d..cfd92f0d3 100644
--- a/tests/app/template/test_rest.py
+++ b/tests/app/template/test_rest.py
@@ -949,7 +949,7 @@ def test_preview_letter_template_precompiled_s3_error(
                 service_id=notification.service_id,
                 notification_id=notification.id,
                 file_type='pdf',
-                _expected_status=404
+                _expected_status=500
             )