diff --git a/app/clients/sms/twilio.py b/app/clients/sms/twilio.py
index 847171861d..81f57e873e 100644
--- a/app/clients/sms/twilio.py
+++ b/app/clients/sms/twilio.py
@@ -176,7 +176,6 @@ def send_sms(
 
         Return: a string containing the Twilio message.sid
         """
-
         start_time = monotonic()
         from app.dao.service_sms_sender_dao import (
             dao_get_service_sms_sender_by_service_id_and_number,
@@ -239,12 +238,12 @@ def send_sms(
             if e.status == 400 and 'phone number' in e.msg:
                 self.logger.exception('Twilio send SMS request for %s failed', reference)
                 raise InvalidProviderException from e
-            # elif e.status == 400 and e.code == 21617:  # Twilio error code for max length exceeded
-            #     self.logger.exception(
-            #         'Twilio send SMS request for %s failed, message content max length exceeded.', reference
-            #     )
-            #     self.logger.debug('Twilio error details for %s - %s: %s', reference, e.code, e.msg)
-            #     raise NonRetryableException('Twilio request failed') from e
+            elif e.status == 400 and e.code == 21617:  # Twilio error code for max length exceeded
+                self.logger.exception(
+                    'Twilio send SMS request for %s failed, message content max length exceeded.', reference
+                )
+                self.logger.debug('Twilio error details for %s - %s: %s', reference, e.code, e.msg)
+                raise NonRetryableException('Twilio request failed') from e
             else:
                 raise
         except:
diff --git a/tests/app/clients/test_twilio.py b/tests/app/clients/test_twilio.py
index 6544efe60d..79a97bda5d 100644
--- a/tests/app/clients/test_twilio.py
+++ b/tests/app/clients/test_twilio.py
@@ -599,19 +599,43 @@ def test_send_sms_twilio_callback(
         assert response_dict['sid'] == twilio_sid
 
 
+@pytest.mark.parametrize(
+    (
+        'response_dict',
+        'exception',
+    ),
+    (
+        (
+            {
+                'code': 21606,
+                'message': "The 'From' phone number provided (+61412345678) is not a valid message-capable Twilio phone number for this destination",
+            },
+            InvalidProviderException,
+        ),
+        (
+            {
+                'code': 21617,
+                'message': 'Unable to create record: The concatenated message body exceeds the 1600 character limit',
+            },
+            NonRetryableException,
+        ),
+    ),
+    ids=(
+        'invalid-from-number',
+        'message-too-long',
+    ),
+)
 def test_send_sms_raises_invalid_provider_error_with_invalid_twilio_number(
     notify_api,
     mocker,
+    response_dict,
+    exception,
 ):
     to = '+61412345678'
     content = 'my message'
     reference = 'my reference'
-    response_dict = {
-        'code': 21606,
-        'message': "The 'From' phone number provided (+61412345678) is not a valid message-capable Twilio phone number for this destination",
-    }
 
-    with pytest.raises(InvalidProviderException):
+    with pytest.raises(exception):
         with requests_mock.Mocker() as r_mock:
             r_mock.post(
                 f'https://api.twilio.com/2010-04-01/Accounts/{twilio_sms_client._account_sid}/Messages.json',