diff --git a/telethon/client/messages.py b/telethon/client/messages.py
index 0f44c229..f2c129fa 100644
--- a/telethon/client/messages.py
+++ b/telethon/client/messages.py
@@ -838,6 +838,8 @@ class MessageMethods:
         entity = await self.get_input_entity(entity)
         if comment_to is not None:
             entity, reply_to = await self._get_comment_data(entity, comment_to)
+        else:
+            reply_to = utils.get_message_id(reply_to)
 
         if isinstance(message, types.Message):
             if buttons is None:
@@ -868,7 +870,7 @@ class MessageMethods:
                 message=message.message or '',
                 silent=silent,
                 background=background,
-                reply_to=types.InputReplyToMessage(utils.get_message_id(reply_to)),
+                reply_to=None if reply_to is None else types.InputReplyToMessage(reply_to),
                 reply_markup=markup,
                 entities=message.entities,
                 clear_draft=clear_draft,
@@ -890,7 +892,7 @@ class MessageMethods:
                 message=message,
                 entities=formatting_entities,
                 no_webpage=not link_preview,
-                reply_to=types.InputReplyToMessage(utils.get_message_id(reply_to)),
+                reply_to=None if reply_to is None else types.InputReplyToMessage(reply_to),
                 clear_draft=clear_draft,
                 silent=silent,
                 background=background,
diff --git a/telethon/client/uploads.py b/telethon/client/uploads.py
index 54e13dfe..dfec45a3 100644
--- a/telethon/client/uploads.py
+++ b/telethon/client/uploads.py
@@ -408,8 +408,9 @@ class UploadMethods:
             raise TypeError('Cannot use {!r} as file'.format(file))
 
         markup = self.build_reply_markup(buttons)
+        reply_to = None if reply_to is None else types.InputReplyToMessage(reply_to)
         request = functions.messages.SendMediaRequest(
-            entity, media, reply_to=types.InputReplyToMessage(reply_to), message=caption,
+            entity, media, reply_to=reply_to, message=caption,
             entities=msg_entities, reply_markup=markup, silent=silent,
             schedule_date=schedule, clear_draft=clear_draft,
             background=background
diff --git a/telethon/tl/custom/inlineresult.py b/telethon/tl/custom/inlineresult.py
index f9444e75..d56b2fe2 100644
--- a/telethon/tl/custom/inlineresult.py
+++ b/telethon/tl/custom/inlineresult.py
@@ -158,7 +158,7 @@ class InlineResult:
             background=background,
             clear_draft=clear_draft,
             hide_via=hide_via,
-            reply_to=types.InputReplyToMessage(reply_id)
+            reply_to=None if reply_id is None else types.InputReplyToMessage(reply_id)
         )
         return self._client._get_response_message(
             req, await self._client(req), entity)