diff --git a/fastmcp_slim/fastmcp/client/client.py b/fastmcp_slim/fastmcp/client/client.py
index 805365ec4..be485bf49 100644
--- a/fastmcp_slim/fastmcp/client/client.py
+++ b/fastmcp_slim/fastmcp/client/client.py
@@ -57,10 +57,7 @@ from fastmcp.client.tasks import (
 from fastmcp.mcp_config import MCPConfig
 from fastmcp.utilities.exceptions import get_catch_handlers
 from fastmcp.utilities.logging import get_logger
-from fastmcp.utilities.timeout import (
-    normalize_timeout_to_seconds,
-    normalize_timeout_to_timedelta,
-)
+from fastmcp.utilities.timeout import normalize_timeout_to_seconds
 
 if TYPE_CHECKING:
     from fastmcp.server import FastMCP
@@ -305,8 +302,8 @@ class Client(
 
         self._progress_handler = progress_handler
 
-        # Convert timeout to timedelta if needed
-        timeout = normalize_timeout_to_timedelta(timeout)
+        # Convert request timeout to float seconds (0 means disabled -> None)
+        read_timeout_seconds = normalize_timeout_to_seconds(timeout)
 
         # handle init handshake timeout (0 means disabled)
         if init_timeout is None:
@@ -320,7 +317,7 @@ class Client(
             "list_roots_callback": None,
             "logging_callback": create_log_callback(log_handler),
             "message_handler": message_handler or TaskNotificationHandler(self),
-            "read_timeout_seconds": timeout,
+            "read_timeout_seconds": read_timeout_seconds,
             "client_info": client_info,
         }
 
diff --git a/fastmcp_slim/fastmcp/client/transports/base.py b/fastmcp_slim/fastmcp/client/transports/base.py
index b21d4efb8..bc13782be 100644
--- a/fastmcp_slim/fastmcp/client/transports/base.py
+++ b/fastmcp_slim/fastmcp/client/transports/base.py
@@ -1,6 +1,5 @@
 import abc
 import contextlib
-import datetime
 from collections.abc import AsyncIterator
 from typing import Literal, TypeVar
 
@@ -23,7 +22,7 @@ ClientTransportT = TypeVar("ClientTransportT", bound="ClientTransport")
 class SessionKwargs(TypedDict, total=False):
     """Keyword arguments for the MCP ClientSession constructor."""
 
-    read_timeout_seconds: datetime.timedelta | None
+    read_timeout_seconds: float | None
     sampling_callback: SamplingFnT | None
     sampling_capabilities: mcp_types.SamplingCapability | None
     list_roots_callback: ListRootsFnT | None