diff --git a/zulip/integrations/bridge_with_matrix/matrix_bridge.py b/zulip/integrations/bridge_with_matrix/matrix_bridge.py
index 77e532c..9b8dd3d 100644
--- a/zulip/integrations/bridge_with_matrix/matrix_bridge.py
+++ b/zulip/integrations/bridge_with_matrix/matrix_bridge.py
@@ -39,10 +39,10 @@ class Bridge_ZulipFatalException(Exception):
 
 def matrix_login(matrix_client: Any, matrix_config: Dict[str, Any]) -> None:
     try:
-        matrix_client.login_with_password(matrix_config["username"], matrix_config["password"])
+        matrix_client.login_with_password(matrix_config["mxid"], matrix_config["password"])
     except MatrixRequestError as exception:
         if exception.code == 403:
-            raise Bridge_FatalMatrixException("Bad username or password.")
+            raise Bridge_FatalMatrixException("Bad mxid or password.")
         else:
             raise Bridge_FatalMatrixException("Check if your server details are correct.")
     except MissingSchema:
@@ -77,7 +77,7 @@ def matrix_to_zulip(
         """
         content = get_message_content_from_event(event, no_noise)
 
-        zulip_bot_user = matrix_config["username"]
+        zulip_bot_user = matrix_config["mxid"]
         # We do this to identify the messages generated from Zulip -> Matrix
         # and we make sure we don't forward it again to the Zulip stream.
         not_from_zulip_bot = event["sender"] != zulip_bot_user
@@ -237,7 +237,7 @@ def write_sample_config(target_path: str, zuliprc: Optional[str]) -> None:
                 OrderedDict(
                     (
                         ("host", "https://matrix.org"),
-                        ("username", "@username:matrix.org"),
+                        ("mxid", "@username:matrix.org"),
                         ("password", "password"),
                         ("room_id", "#zulip:matrix.org"),
                     )
diff --git a/zulip/integrations/bridge_with_matrix/test_matrix.py b/zulip/integrations/bridge_with_matrix/test_matrix.py
index 3952abc..34bf199 100644
--- a/zulip/integrations/bridge_with_matrix/test_matrix.py
+++ b/zulip/integrations/bridge_with_matrix/test_matrix.py
@@ -18,7 +18,7 @@ sample_config_path = "matrix_test.conf"
 
 sample_config_text = """[matrix]
 host = https://matrix.org
-username = @username:matrix.org
+mxid = @username:matrix.org
 password = password
 room_id = #zulip:matrix.org