diff --git a/src/saic_ismart_client_ng/exceptions.py b/src/saic_ismart_client_ng/exceptions.py
index 93e266c..c7fad69 100644
--- a/src/saic_ismart_client_ng/exceptions.py
+++ b/src/saic_ismart_client_ng/exceptions.py
@@ -16,6 +16,10 @@ class SaicLogoutException(SaicApiException):
     pass
 
 
+class SaicApiClosedException(SaicApiException):
+    pass
+
+
 class SaicApiRetryException(SaicApiException):
     def __init__(
         self, msg: str, *, event_id: str, return_code: int | None = None
diff --git a/src/saic_ismart_client_ng/net/client/__init__.py b/src/saic_ismart_client_ng/net/client/__init__.py
index af19147..47b0918 100644
--- a/src/saic_ismart_client_ng/net/client/__init__.py
+++ b/src/saic_ismart_client_ng/net/client/__init__.py
@@ -7,6 +7,7 @@
 import httpx
 from httpx import Request, Response, Timeout
 
+from saic_ismart_client_ng.exceptions import SaicApiClosedException
 from saic_ismart_client_ng.net.httpx import (
     decrypt_httpx_response,
     encrypt_httpx_request,
@@ -27,6 +28,7 @@ def __init__(
         self.__listener = listener
         self.__logger = logging.getLogger(__name__)
         self.__user_token: str = ""
+        self.__closed = False
         self.__client = httpx.AsyncClient(
             timeout=Timeout(timeout=configuration.read_timeout),
             event_hooks={
@@ -36,9 +38,13 @@ def __init__(
         )
 
     async def send(self, request: Request) -> Response:
+        if self.__closed:
+            msg = "The API client has been closed and cannot be reused"
+            raise SaicApiClosedException(msg)
         return await self.__client.send(request)
 
     async def close(self) -> None:
+        self.__closed = True
         await self.__client.aclose()
 
     @property
diff --git a/tests/test_close.py b/tests/test_close.py
index d0012fe..807ecd2 100644
--- a/tests/test_close.py
+++ b/tests/test_close.py
@@ -1,13 +1,28 @@
+from __future__ import annotations
+
 import unittest
 
+import pytest
+
 from saic_ismart_client_ng import SaicApi
+from saic_ismart_client_ng.exceptions import SaicApiClosedException
 from saic_ismart_client_ng.model import SaicApiConfiguration
 
 
+def _build_api() -> SaicApi:
+    return SaicApi(
+        SaicApiConfiguration(username="user", password="pass"),  # noqa: S106
+    )
+
+
 class TestClose(unittest.IsolatedAsyncioTestCase):
     async def test_close_is_idempotent(self) -> None:
-        api = SaicApi(
-            SaicApiConfiguration(username="user", password="pass"),
-        )
+        api = _build_api()
+        await api.close()
         await api.close()
+
+    async def test_login_after_close_raises(self) -> None:
+        api = _build_api()
         await api.close()
+        with pytest.raises(SaicApiClosedException):
+            await api.login()