diff --git a/CHANGES/9406.misc.rst b/CHANGES/9406.misc.rst
new file mode 100644
index 00000000000..0a0f7e78677
--- /dev/null
+++ b/CHANGES/9406.misc.rst
@@ -0,0 +1 @@
+Reduced memory required for timer objects created during the client request lifecycle -- by :user:`bdraco`.
diff --git a/aiohttp/helpers.py b/aiohttp/helpers.py
index 13a531d5cab..bc626fd939e 100644
--- a/aiohttp/helpers.py
+++ b/aiohttp/helpers.py
@@ -581,6 +581,8 @@ def calculate_timeout_when(
 class TimeoutHandle:
     """Timeout handle"""
 
+    __slots__ = ("_timeout", "_loop", "_ceil_threshold", "_callbacks")
+
     def __init__(
         self,
         loop: asyncio.AbstractEventLoop,
@@ -629,11 +631,17 @@ def __call__(self) -> None:
 
 
 class BaseTimerContext(ContextManager["BaseTimerContext"]):
+
+    __slots__ = ()
+
     def assert_timeout(self) -> None:
         """Raise TimeoutError if timeout has been exceeded."""
 
 
 class TimerNoop(BaseTimerContext):
+
+    __slots__ = ()
+
     def __enter__(self) -> BaseTimerContext:
         return self
 
@@ -649,6 +657,8 @@ def __exit__(
 class TimerContext(BaseTimerContext):
     """Low resolution timeout context manager"""
 
+    __slots__ = ("_loop", "_tasks", "_cancelled", "_cancelling")
+
     def __init__(self, loop: asyncio.AbstractEventLoop) -> None:
         self._loop = loop
         self._tasks: List[asyncio.Task[Any]] = []
diff --git a/pyproject.toml b/pyproject.toml
index 85d7c87eb34..33962686919 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -82,3 +82,8 @@ skip = "pp*"
 [tool.codespell]
 skip = '.git,*.pdf,*.svg,Makefile,CONTRIBUTORS.txt,venvs,_build'
 ignore-words-list = 'te'
+
+[tool.slotscheck]
+# TODO(3.13): Remove aiohttp.helpers once https://github.com/python/cpython/pull/106771
+# is available in all supported cpython versions
+exclude-modules = "(^aiohttp\\.helpers)"