diff --git a/aiogram/api/client/base.py b/aiogram/api/client/base.py
index 2f5ebcda..bbb3f974 100644
--- a/aiogram/api/client/base.py
+++ b/aiogram/api/client/base.py
@@ -2,8 +2,8 @@ from typing import TypeVar
 
 from ...utils.mixins import ContextInstanceMixin
 from ..methods import TelegramMethod
-from aiogram.api.client.session.aiohttp import AiohttpSession
-from aiogram.api.client.session.base import BaseSession
+from .session.aiohttp import AiohttpSession
+from .session.base import BaseSession
 
 T = TypeVar("T")
 
diff --git a/aiogram/api/client/session/aiohttp.py b/aiogram/api/client/session/aiohttp.py
index 33da0c3f..d9f65b2b 100644
--- a/aiogram/api/client/session/aiohttp.py
+++ b/aiogram/api/client/session/aiohttp.py
@@ -3,6 +3,7 @@ from typing import Callable, Optional, TypeVar, cast
 from aiohttp import ClientSession, FormData
 
 from aiogram.api.methods import Request, TelegramMethod
+
 from .base import PRODUCTION, BaseSession, TelegramAPIServer
 
 T = TypeVar("T")
diff --git a/tests/test_api/test_client/test_session/test_aiohttp_session.py b/tests/test_api/test_client/test_session/test_aiohttp_session.py
new file mode 100644
index 00000000..35284e62
--- /dev/null
+++ b/tests/test_api/test_client/test_session/test_aiohttp_session.py
@@ -0,0 +1,102 @@
+import aiohttp
+import pytest
+from aresponses import ResponsesMockServer
+from asynctest import CoroutineMock, patch
+
+from aiogram.api.client.session.aiohttp import AiohttpSession
+from aiogram.api.methods import Request, TelegramMethod
+from aiogram.api.types import InputFile
+
+
+class BareInputFile(InputFile):
+    async def read(self, chunk_size: int):
+        yield b""
+
+
+class TestAiohttpSession:
+    @pytest.mark.asyncio
+    async def test_create_session(self):
+        session = AiohttpSession()
+
+        assert session._session is None
+        aiohttp_session = await session.create_session()
+        assert session._session is not None
+        assert isinstance(aiohttp_session, aiohttp.ClientSession)
+
+    @pytest.mark.asyncio
+    async def test_close_session(self):
+        session = AiohttpSession()
+        await session.create_session()
+
+        with patch("aiohttp.ClientSession.close", new=CoroutineMock()) as mocked_close:
+            await session.close()
+            mocked_close.assert_called_once()
+
+    def test_build_form_data_with_data_only(self):
+        request = Request(
+            method="method",
+            data={
+                "str": "value",
+                "int": 42,
+                "bool": True,
+                "null": None,
+                "list": ["foo"],
+                "dict": {"bar": "baz"},
+            },
+        )
+
+        session = AiohttpSession()
+        form = session.build_form_data(request)
+
+        fields = form._fields
+        assert len(fields) == 5
+        assert all(isinstance(field[2], str) for field in fields)
+        assert "null" not in [item[0]["name"] for item in fields]
+
+    def test_build_form_data_with_files(self):
+        request = Request(
+            method="method",
+            data={"key": "value"},
+            files={"document": BareInputFile(filename="file.txt")},
+        )
+
+        session = AiohttpSession()
+        form = session.build_form_data(request)
+
+        fields = form._fields
+
+        assert len(fields) == 2
+        assert fields[1][0]["name"] == "document"
+        assert fields[1][0]["filename"] == "file.txt"
+        assert isinstance(fields[1][2], BareInputFile)
+
+    @pytest.mark.asyncio
+    async def test_make_request(self, aresponses: ResponsesMockServer):
+        aresponses.add(
+            aresponses.ANY,
+            "/botTOKEN/method",
+            "post",
+            aresponses.Response(
+                status=200,
+                text='{"ok": true, "result": 42}',
+                headers={"Content-Type": "application/json"},
+            ),
+        )
+
+        session = AiohttpSession()
+
+        class TestMethod(TelegramMethod[int]):
+            __returning__ = int
+
+            def build_request(self) -> Request:
+                return Request(method="method", data={})
+
+        call = TestMethod()
+        with patch(
+            "aiogram.api.client.session.base.BaseSession.raise_for_status"
+        ) as patched_raise_for_status:
+            result = await session.make_request("TOKEN", call)
+            assert isinstance(result, int)
+            assert result == 42
+
+            assert patched_raise_for_status.called_once()
diff --git a/tests/test_api/test_client/test_session/test_base_session.py b/tests/test_api/test_client/test_session/test_base_session.py
index a74a440b..34c2e8fb 100644
--- a/tests/test_api/test_client/test_session/test_base_session.py
+++ b/tests/test_api/test_client/test_session/test_base_session.py
@@ -5,6 +5,7 @@ import pytest
 from asynctest import CoroutineMock
 
 from aiogram.api.client.session.base import BaseSession
+from aiogram.api.methods import GetMe, Response
 from aiogram.utils.mixins import DataMixin
 
 
@@ -20,7 +21,7 @@ class TestBaseSession(DataMixin):
         session = BaseSession()
 
         with patch(
-            "aiogram.api.session.base.BaseSession.close", new=CoroutineMock()
+            "aiogram.api.client.session.base.BaseSession.close", new=CoroutineMock()
         ) as mocked_close:
             session.__del__()
             mocked_close.assert_called_once_with()
@@ -30,10 +31,10 @@ class TestBaseSession(DataMixin):
         session = BaseSession()
 
         with patch(
-            "aiogram.api.session.base.BaseSession.close", new=CoroutineMock()
+            "aiogram.api.client.session.base.BaseSession.close", new=CoroutineMock()
         ) as mocked_close:
             session.__del__()
-            mocked_close.assert_called_once_with()
+            mocked_close.assert_called_once()
 
     def test_prepare_value(self):
         session = BaseSession()
@@ -87,3 +88,16 @@ class TestBaseSession(DataMixin):
         session = BaseSession()
 
         assert session.clean_json(42) == 42
+
+    def test_raise_for_status(self):
+        session = BaseSession()
+
+        session.raise_for_status(Response[bool](ok=True, result=True))
+        with pytest.raises(Exception):
+            session.raise_for_status(Response[bool](ok=False, description="Error", error_code=400))
+
+    @pytest.mark.asyncio
+    async def test_make_request(self):
+        session = BaseSession()
+
+        assert await session.make_request("TOKEN", GetMe()) is None