diff --git a/telethon/telegram_bare_client.py b/telethon/telegram_bare_client.py
index 498b749e..14e02acf 100644
--- a/telethon/telegram_bare_client.py
+++ b/telethon/telegram_bare_client.py
@@ -13,8 +13,9 @@ from . import helpers as utils, version
 from .crypto import rsa, CdnDecrypter
 from .errors import (
     RPCError, BrokenAuthKeyError, ServerError,
-    FloodWaitError, FileMigrateError, TypeNotFoundError,
-    UnauthorizedError, PhoneMigrateError, NetworkMigrateError, UserMigrateError
+    FloodWaitError, FloodTestPhoneWaitError, FileMigrateError,
+    TypeNotFoundError, UnauthorizedError, PhoneMigrateError,
+    NetworkMigrateError, UserMigrateError
 )
 from .network import authenticator, MtProtoSender, Connection, ConnectionMode
 from .tl import TLObject, Session
@@ -546,7 +547,7 @@ class TelegramBareClient:
             # Telegram is having some issues, just retry
             __log__.error('Telegram servers are having internal errors %s', e)
 
-        except FloodWaitError as e:
+        except (FloodWaitError, FloodTestPhoneWaitError) as e:
             __log__.warning('Request invoked too often, wait %ds', e.seconds)
             if e.seconds > self.session.flood_sleep_threshold | 0:
                 raise
diff --git a/telethon_generator/error_descriptions b/telethon_generator/error_descriptions
index 65894ba1..2754ce5e 100644
--- a/telethon_generator/error_descriptions
+++ b/telethon_generator/error_descriptions
@@ -63,3 +63,4 @@ SESSION_REVOKED=The authorization has been invalidated, because of the user term
 USER_ALREADY_PARTICIPANT=The authenticated user is already a participant of the chat
 USER_DEACTIVATED=The user has been deleted/deactivated
 FLOOD_WAIT_X=A wait of {} seconds is required
+FLOOD_TEST_PHONE_WAIT_X=A wait of {} seconds is required in the test servers
diff --git a/telethon_generator/error_generator.py b/telethon_generator/error_generator.py
index 30163dfc..5b14f22e 100644
--- a/telethon_generator/error_generator.py
+++ b/telethon_generator/error_generator.py
@@ -79,7 +79,9 @@ def generate_code(output, json_file, errors_desc):
     errors = defaultdict(set)
     # PWRTelegram's API doesn't return all errors, which we do need here.
     # Add some special known-cases manually first.
-    errors[420].add('FLOOD_WAIT_X')
+    errors[420].update((
+        'FLOOD_WAIT_X', 'FLOOD_TEST_PHONE_WAIT_X'
+    ))
     errors[401].update((
         'AUTH_KEY_INVALID', 'SESSION_EXPIRED', 'SESSION_REVOKED'
     ))
@@ -118,6 +120,7 @@ def generate_code(output, json_file, errors_desc):
     # Names for the captures, or 'x' if unknown
     capture_names = {
         'FloodWaitError': 'seconds',
+        'FloodTestPhoneWaitError': 'seconds',
         'FileMigrateError': 'new_dc',
         'NetworkMigrateError': 'new_dc',
         'PhoneMigrateError': 'new_dc',