diff --git a/src/vws/async_query.py b/src/vws/async_query.py
index c229569e..bebd3089 100644
--- a/src/vws/async_query.py
+++ b/src/vws/async_query.py
@@ -64,9 +64,7 @@ def __init__(
 
     async def aclose(self) -> None:
         """Close the underlying transport if it supports closing."""
-        close = getattr(self._transport, "aclose", None)
-        if close is not None:
-            await close()
+        await self._transport.aclose()
 
     async def __aenter__(self) -> Self:
         """Enter the async context manager."""
diff --git a/src/vws/async_vumark_service.py b/src/vws/async_vumark_service.py
index a104f49c..51c2ef34 100644
--- a/src/vws/async_vumark_service.py
+++ b/src/vws/async_vumark_service.py
@@ -50,9 +50,7 @@ def __init__(
 
     async def aclose(self) -> None:
         """Close the underlying transport if it supports closing."""
-        close = getattr(self._transport, "aclose", None)
-        if close is not None:
-            await close()
+        await self._transport.aclose()
 
     async def __aenter__(self) -> Self:
         """Enter the async context manager."""
diff --git a/src/vws/async_vws.py b/src/vws/async_vws.py
index feba724d..92675ac1 100644
--- a/src/vws/async_vws.py
+++ b/src/vws/async_vws.py
@@ -61,9 +61,7 @@ def __init__(
 
     async def aclose(self) -> None:
         """Close the underlying transport if it supports closing."""
-        close = getattr(self._transport, "aclose", None)
-        if close is not None:
-            await close()
+        await self._transport.aclose()
 
     async def __aenter__(self) -> Self:
         """Enter the async context manager."""
diff --git a/src/vws/transports.py b/src/vws/transports.py
index 6bf9ceb9..5b261883 100644
--- a/src/vws/transports.py
+++ b/src/vws/transports.py
@@ -167,6 +167,10 @@ class AsyncTransport(Protocol):
     and returns a ``Response``.
     """
 
+    async def aclose(self) -> None:
+        """Close the transport and release resources."""
+        ...  # pylint: disable=unnecessary-ellipsis
+
     def __call__(
         self,
         *,
diff --git a/tests/test_transports.py b/tests/test_transports.py
index b8a34f70..96518f16 100644
--- a/tests/test_transports.py
+++ b/tests/test_transports.py
@@ -6,7 +6,6 @@
 import pytest
 import respx
 
-from vws import AsyncCloudRecoService, AsyncVuMarkService, AsyncVWS
 from vws.response import Response
 from vws.transports import AsyncHTTPXTransport, HTTPXTransport
 
@@ -140,67 +139,3 @@ async def test_context_manager() -> None:
         assert route.called
         assert isinstance(response, Response)
         assert response.status_code == HTTPStatus.OK
-
-
-class _NoCloseTransport:
-    """A minimal async transport without ``aclose``."""
-
-    async def __call__(  # pragma: no cover
-        self,
-        *,
-        method: str,
-        url: str,
-        headers: dict[str, str],
-        data: bytes,
-        request_timeout: float | tuple[float, float],
-    ) -> Response:
-        """Not implemented."""
-        raise NotImplementedError
-
-
-_DUMMY_KEY = "x"
-
-
-class TestAsyncClientAclose:
-    """Tests for ``aclose`` on async clients with transports that
-    lack ``aclose``.
-    """
-
-    @staticmethod
-    @pytest.mark.asyncio
-    async def test_vws_aclose_no_transport_aclose() -> None:
-        """``AsyncVWS.aclose`` works when the transport has no
-        ``aclose``.
-        """
-        client = AsyncVWS(
-            server_access_key=_DUMMY_KEY,
-            server_secret_key=_DUMMY_KEY,
-            transport=_NoCloseTransport(),
-        )
-        await client.aclose()
-
-    @staticmethod
-    @pytest.mark.asyncio
-    async def test_cloud_reco_aclose_no_transport_aclose() -> None:
-        """``AsyncCloudRecoService.aclose`` works when the transport
-        has no ``aclose``.
-        """
-        client = AsyncCloudRecoService(
-            client_access_key=_DUMMY_KEY,
-            client_secret_key=_DUMMY_KEY,
-            transport=_NoCloseTransport(),
-        )
-        await client.aclose()
-
-    @staticmethod
-    @pytest.mark.asyncio
-    async def test_vumark_aclose_no_transport_aclose() -> None:
-        """``AsyncVuMarkService.aclose`` works when the transport
-        has no ``aclose``.
-        """
-        client = AsyncVuMarkService(
-            server_access_key=_DUMMY_KEY,
-            server_secret_key=_DUMMY_KEY,
-            transport=_NoCloseTransport(),
-        )
-        await client.aclose()