diff --git a/twitchio/client.py b/twitchio/client.py
index 97460d06..cc9c09df 100644
--- a/twitchio/client.py
+++ b/twitchio/client.py
@@ -76,7 +76,7 @@ def __init__(
         token: str,
         *,
         client_secret: str = None,
-        initial_channels: Union[list, tuple, Callable] = None,
+        initial_channels: Union[List[str], Tuple[str, ...], Callable[[], Union[List[str], Tuple[str, ...]]], None] = None,
         loop: asyncio.AbstractEventLoop = None,
         heartbeat: Optional[float] = 30.0,
         retain_cache: Optional[bool] = True,
diff --git a/twitchio/ext/commands/bot.py b/twitchio/ext/commands/bot.py
index 942839d4..8e7ff049 100644
--- a/twitchio/ext/commands/bot.py
+++ b/twitchio/ext/commands/bot.py
@@ -31,7 +31,7 @@
 import types
 import warnings
 from functools import partial
-from typing import Callable, Optional, Union, Coroutine, Dict, List, TYPE_CHECKING, Mapping, Awaitable
+from typing import Callable, Optional, Union, Coroutine, Dict, List, Tuple, TYPE_CHECKING, Mapping, Awaitable
 
 from twitchio.client import Client
 from twitchio.http import TwitchHTTP
@@ -53,7 +53,7 @@ def __init__(
         *,
         prefix: Union[str, list, tuple, set, Callable, Coroutine],
         client_secret: str = None,
-        initial_channels: Union[list, tuple, Callable] = None,
+        initial_channels: Union[List[str], Tuple[str, ...], Callable[[], Union[List[str], Tuple[str, ...]]], None] = None,
         heartbeat: Optional[float] = 30.0,
         retain_cache: Optional[bool] = True,
         **kwargs,
diff --git a/twitchio/websocket.py b/twitchio/websocket.py
index da61a6a1..085486b7 100644
--- a/twitchio/websocket.py
+++ b/twitchio/websocket.py
@@ -31,7 +31,7 @@
 import time
 import traceback
 from functools import partial
-from typing import Union, Optional, List, TYPE_CHECKING
+from typing import Union, Callable, Optional, List, Tuple, TYPE_CHECKING
 
 import aiohttp
 
@@ -57,7 +57,7 @@ def __init__(
         client: "Client",
         token: str = None,
         modes: tuple = None,
-        initial_channels: List[str] = None,
+        initial_channels: Union[List[str], Tuple[str, ...], Callable[[], Union[List[str], Tuple[str, ...]]], None] = None,
         retain_cache: Optional[bool] = True,
     ):
         self._loop = loop