diff --git a/README.md b/README.md
index d01e219f5e62..8f7a4ee56a2c 100644
--- a/README.md
+++ b/README.md
@@ -404,4 +404,4 @@ Copyright 2021 Rasa Technologies GmbH. [Copy of the license](LICENSE.txt).
 
 A list of the Licenses of the dependencies of the project can be found at
 the bottom of the
-[Libraries Summary](https://libraries.io/github/RasaHQ/rasa).
+[Libraries Summary](https://libraries.io/github/RasaHQ/rasa).
\ No newline at end of file
diff --git a/changelog/5657.improvement.md b/changelog/5657.improvement.md
new file mode 100644
index 000000000000..2063dd6cc3da
--- /dev/null
+++ b/changelog/5657.improvement.md
@@ -0,0 +1 @@
+Add list handling in the `send_custom_json` method on `channels/facebook.py`.
diff --git a/rasa/core/channels/facebook.py b/rasa/core/channels/facebook.py
index 16b4a6568ab7..4526a9b76e0b 100644
--- a/rasa/core/channels/facebook.py
+++ b/rasa/core/channels/facebook.py
@@ -10,7 +10,7 @@
 import rasa.shared.utils.io
 from sanic import Blueprint, response
 from sanic.request import Request
-from typing import Text, List, Dict, Any, Callable, Awaitable, Iterable, Optional
+from typing import Text, List, Dict, Any, Callable, Awaitable, Iterable, Optional, Union
 
 from rasa.core.channels.channel import UserMessage, OutputChannel, InputChannel
 from sanic.response import HTTPResponse
@@ -276,11 +276,14 @@ async def send_elements(
         self.messenger_client.send(payload, recipient_id, "RESPONSE")
 
     async def send_custom_json(
-        self, recipient_id: Text, json_message: Dict[Text, Any], **kwargs: Any
+        self,
+        recipient_id: Text,
+        json_message: Union[List, Dict[Text, Any]],
+        **kwargs: Any,
     ) -> None:
         """Sends custom json data to the output."""
-
-        recipient_id = json_message.pop("sender", {}).pop("id", None) or recipient_id
+        if isinstance(json_message, dict) and "sender" in json_message.keys():
+            recipient_id = json_message.pop("sender", {}).pop("id", recipient_id)
 
         self.messenger_client.send(json_message, recipient_id, "RESPONSE")
 
diff --git a/tests/test_facebook.py b/tests/test_facebook.py
new file mode 100644
index 000000000000..ec2f269f1638
--- /dev/null
+++ b/tests/test_facebook.py
@@ -0,0 +1,91 @@
+import logging
+from rasa.core.channels.facebook import MessengerBot
+from fbmessenger import MessengerClient
+
+from _pytest.monkeypatch import MonkeyPatch
+
+import rasa.core.run
+from rasa.core import utils
+
+
+# this is needed so that the tests included as code examples look better
+from tests.utilities import json_of_latest_request, latest_request
+
+logger = logging.getLogger(__name__)
+
+
+def test_facebook_channel():
+    from rasa.core.channels.facebook import FacebookInput
+
+    input_channel = FacebookInput(
+        fb_verify="YOUR_FB_VERIFY",
+        # you need tell facebook this token, to confirm your URL
+        fb_secret="YOUR_FB_SECRET",  # your app secret
+        fb_access_token="YOUR_FB_PAGE_ACCESS_TOKEN"
+        # token for the page you subscribed to
+    )
+
+    s = rasa.core.run.configure_app([input_channel], port=5004)
+
+    routes_list = utils.list_routes(s)
+
+    assert routes_list["fb_webhook.health"].startswith("/webhooks/facebook")
+    assert routes_list["fb_webhook.webhook"].startswith("/webhooks/facebook/webhook")
+
+
+async def test_facebook_send_custom_json():
+    # This function tests cases when the custom json is a list
+    # The send_custom_json function doesn't return anything. Rather
+    # it calls an object MessengerClient, that will
+    # then make a post request.
+    # Since the purpose is to test the extraction of the recipient_id
+    # by the MessengerBot.send_custom_json_list we
+    # modify MessengerClient (from the fbmessenger pypackage) to
+    # return the recipient ID.
+
+    json_without_id = {
+        "blocks": [
+            {"type": "title", "text": {"text": "Conversation progress"}},
+            {
+                "type": "progression_bar",
+                "text": {"text": "progression 1", "level": "1"},
+            },
+        ]
+    }
+    json_with_id = {
+        "blocks": [
+            {"type": "title", "text": {"text": "Conversation progress"}},
+            {
+                "type": "progression_bar",
+                "text": {"text": "progression 1", "level": "1"},
+            },
+        ],
+        "sender": {"id": "test_json_id"},
+    }
+
+    class TestableMessengerClient(MessengerClient):
+        def __init__(self, page_access_token, **kwargs):
+            self.recipient_id = ""
+            super(TestableMessengerClient, self).__init__(page_access_token, **kwargs)
+
+        def send(
+            self,
+            payload,
+            recipient_id,
+            messaging_type="RESPONSE",
+            notification_type="REGULAR",
+            timeout=None,
+            tag=None,
+        ):
+            self.recipient_id = recipient_id
+
+    messenger_client = TestableMessengerClient(page_access_token="test_token")
+    messenger_bot = MessengerBot(messenger_client)
+    await messenger_bot.send_custom_json(
+        recipient_id="test_id", json_message=json_without_id
+    )
+    assert messenger_bot.messenger_client.recipient_id == "test_id"
+    await messenger_bot.send_custom_json(
+        recipient_id="test_id", json_message=json_with_id
+    )
+    assert messenger_bot.messenger_client.recipient_id == "test_json_id"