diff --git a/doc/changelog.d/4558.added.md b/doc/changelog.d/4558.added.md
new file mode 100644
index 000000000000..d69c90b17e99
--- /dev/null
+++ b/doc/changelog.d/4558.added.md
@@ -0,0 +1 @@
+PathLike support throughout
diff --git a/src/ansys/fluent/core/_types.py b/src/ansys/fluent/core/_types.py
new file mode 100644
index 000000000000..639a5018146b
--- /dev/null
+++ b/src/ansys/fluent/core/_types.py
@@ -0,0 +1,35 @@
+# Copyright (C) 2021 - 2025 ANSYS, Inc. and/or its affiliates.
+# SPDX-License-Identifier: MIT
+#
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+
+"""Common type aliases for PyFluent.
+
+This module centralizes reusable typing constructs
+"""
+
+from __future__ import annotations
+
+import os
+from typing import TypeAlias
+
+PathType: TypeAlias = "os.PathLike[str] | os.PathLike[bytes] | str | bytes"
+"""Type alias for file system paths."""
diff --git a/src/ansys/fluent/core/examples/downloads.py b/src/ansys/fluent/core/examples/downloads.py
index f41527e71ccd..c5bf7405418d 100644
--- a/src/ansys/fluent/core/examples/downloads.py
+++ b/src/ansys/fluent/core/examples/downloads.py
@@ -30,6 +30,7 @@
 import zipfile
 
 import ansys.fluent.core as pyfluent
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.utils.networking import check_url_exists, get_url_content
 
 logger = logging.getLogger("pyfluent.networking")
@@ -65,16 +66,14 @@ def _decompress(file_name: str) -> None:
 def _get_file_url(file_name: str, directory: str | None = None) -> str:
     """Get file URL."""
     if directory:
-        return (
-            "https://github.com/ansys/example-data/raw/main/" f"{directory}/{file_name}"
-        )
+        return f"https://github.com/ansys/example-data/raw/main/{directory}/{file_name}"
     return f"https://github.com/ansys/example-data/raw/main/{file_name}"
 
 
 def _retrieve_file(
     url: str,
     file_name: str,
-    save_path: str | None = None,
+    save_path: "PathType | None" = None,
     return_without_path: bool | None = False,
 ) -> str:
     """Download specified file from specified URL."""
@@ -121,7 +120,7 @@ def _retrieve_file(
 def download_file(
     file_name: str,
     directory: str | None = None,
-    save_path: str | None = None,
+    save_path: "PathType | None" = None,
     return_without_path: bool | None = None,
 ) -> str:
     """Download specified example file from the Ansys example data repository.
diff --git a/src/ansys/fluent/core/filereader/case_file.py b/src/ansys/fluent/core/filereader/case_file.py
index 6150307632ee..20fce2b726c3 100644
--- a/src/ansys/fluent/core/filereader/case_file.py
+++ b/src/ansys/fluent/core/filereader/case_file.py
@@ -48,6 +48,7 @@
 import defusedxml.ElementTree as ET
 import numpy as np
 
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.solver.error_message import allowed_name_error_message
 
 from . import lispy
@@ -616,17 +617,17 @@ class CaseFile(RPVarProcessor):
 
     def __init__(
         self,
-        case_file_name: str | None = None,
-        project_file_name: str | None = None,
+        case_file_name: "PathType | None" = None,
+        project_file_name: "PathType | None" = None,
     ) -> None:
         """Initialize a CaseFile object. Exactly one file path argument must be
         specified.
 
         Parameters
         ----------
-        case_file_name : str
+        case_file_name : :class:`os.PathLike` | str | None
             The path of a case file.
-        project_file_name : str
+        project_file_name : :class:`os.PathLike` | str | None
             The path of a project file from which the case file is selected.
         """
         self._is_case_file = False
diff --git a/src/ansys/fluent/core/launcher/launcher.py b/src/ansys/fluent/core/launcher/launcher.py
index 335c7c0ea82c..ecb8d8555194 100644
--- a/src/ansys/fluent/core/launcher/launcher.py
+++ b/src/ansys/fluent/core/launcher/launcher.py
@@ -32,6 +32,7 @@
 from typing import Any, Dict
 
 import ansys.fluent.core as pyfluent
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.fluent_connection import FluentConnection
 from ansys.fluent.core.launcher.container_launcher import DockerLauncher
 from ansys.fluent.core.launcher.launch_options import (
@@ -167,14 +168,14 @@ def launch_fluent(
     graphics_driver: (
         FluentWindowsGraphicsDriver | FluentLinuxGraphicsDriver | str | None
     ) = None,
-    case_file_name: str | None = None,
-    case_data_file_name: str | None = None,
+    case_file_name: "PathType | None" = None,
+    case_data_file_name: "PathType | None" = None,
     lightweight_mode: bool | None = None,
     mode: FluentMode | str | None = None,
     py: bool | None = None,
     gpu: bool | list[int] | None = None,
-    cwd: str | None = None,
-    fluent_path: str | None = None,
+    cwd: "PathType | None" = None,
+    fluent_path: "PathType | None" = None,
     topy: str | list | None = None,
     start_watchdog: bool | None = None,
     scheduler_options: dict | None = None,
@@ -255,9 +256,9 @@ def launch_fluent(
        ``"null"``, ``"x11"``, ``"opengl2"``, ``"opengl"`` or ``"auto"``. The default is
        ``FluentWindowsGraphicsDriver.AUTO`` in Windows and
        ``FluentLinuxGraphicsDriver.AUTO`` in Linux.
-    case_file_name : str, optional
+    case_file_name : :class:`os.PathLike` or str, optional
         If provided, the case file at ``case_file_name`` is read into the Fluent session.
-    case_data_file_name : str, optional
+    case_data_file_name : :class:`os.PathLike` or str, optional
         If provided, the case and data files at ``case_data_file_name`` are read into the Fluent session.
     lightweight_mode : bool, optional
         Whether to run in lightweight mode. In lightweight mode, the lightweight settings are read into the
@@ -279,9 +280,9 @@ def launch_fluent(
         clamped to the value of ``processor_count``. Please refer to
         *Starting the Fluent GPU Solver* section in *Fluent's User Guide* for more
         information like how to determine the GPU IDs.
-    cwd : str, Optional
+    cwd : :class:`os.PathLike` or str, optional
         Working directory for the Fluent client.
-    fluent_path: str, Optional
+    fluent_path: :class:`os.PathLike` or str, optional
         User provided Fluent installation path.
     topy : bool or str, optional
         A boolean flag to write the equivalent Python journal(s) from the journal(s) passed.
diff --git a/src/ansys/fluent/core/launcher/slurm_launcher.py b/src/ansys/fluent/core/launcher/slurm_launcher.py
index 90af1df1f9fd..08a7683a8cf6 100644
--- a/src/ansys/fluent/core/launcher/slurm_launcher.py
+++ b/src/ansys/fluent/core/launcher/slurm_launcher.py
@@ -70,6 +70,7 @@
 import time
 from typing import Any, Callable, Dict
 
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.exceptions import InvalidArgument
 from ansys.fluent.core.launcher.launch_options import (
     Dimension,
@@ -298,13 +299,13 @@ def __init__(
         env: Dict[str, Any] | None = None,
         cleanup_on_exit: bool = True,
         start_transcript: bool = True,
-        case_file_name: str | None = None,
-        case_data_file_name: str | None = None,
+        case_file_name: "PathType | None" = None,
+        case_data_file_name: "PathType | None" = None,
         lightweight_mode: bool | None = None,
         py: bool | None = None,
         gpu: bool | None = None,
-        cwd: str | None = None,
-        fluent_path: str | None = None,
+        cwd: "PathType | None" = None,
+        fluent_path: "PathType | None" = None,
         topy: str | list | None = None,
         start_watchdog: bool | None = None,
         scheduler_options: dict | None = None,
@@ -360,10 +361,10 @@ def __init__(
             default is ``True``. You can stop and start the streaming of the
             Fluent transcript subsequently via the method calls, ``transcript.start()``
             and ``transcript.stop()`` on the session object.
-        case_file_name : str, optional
+        case_file_name : :class:`os.PathLike` or str, optional
             Name of the case file to read into the
             Fluent session. The default is ``None``.
-        case_data_file_name : str, optional
+        case_data_file_name : :class:`os.PathLike` or str, optional
             Name of the case data file. If names of both a case file and case data file are provided, they are read into the Fluent session.
         lightweight_mode : bool, optional
             Whether to run in lightweight mode. In lightweight mode, the lightweight settings are read into the
@@ -376,9 +377,9 @@ def __init__(
             If True, Fluent will run in Python mode. Default is None.
         gpu : bool, optional
             If True, Fluent will start with GPU Solver.
-        cwd : str, Optional
+        cwd : :class:`os.PathLike` or str, optional
             Working directory for the Fluent client.
-        fluent_path: str, Optional
+        fluent_path: :class:`os.PathLike` or str, optional
             User provided Fluent installation path.
         topy : bool or str, optional
             A boolean flag to write the equivalent Python journal(s) from the journal(s) passed.
diff --git a/src/ansys/fluent/core/launcher/standalone_launcher.py b/src/ansys/fluent/core/launcher/standalone_launcher.py
index 34ca6a85640e..1c52ab562569 100644
--- a/src/ansys/fluent/core/launcher/standalone_launcher.py
+++ b/src/ansys/fluent/core/launcher/standalone_launcher.py
@@ -42,6 +42,7 @@
 import subprocess
 from typing import Any, Dict
 
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.launcher.error_handler import (
     LaunchFluentError,
     _raise_non_gui_exception_in_windows,
@@ -95,13 +96,13 @@ def __init__(
         cleanup_on_exit: bool = True,
         dry_run: bool = False,
         start_transcript: bool = True,
-        case_file_name: str | None = None,
-        case_data_file_name: str | None = None,
+        case_file_name: "PathType | None" = None,
+        case_data_file_name: "PathType | None" = None,
         lightweight_mode: bool | None = None,
         py: bool | None = None,
         gpu: bool | None = None,
-        cwd: str | None = None,
-        fluent_path: str | None = None,
+        cwd: "PathType | None" = None,
+        fluent_path: "PathType | None" = None,
         topy: str | list | None = None,
         start_watchdog: bool | None = None,
         file_transfer_service: Any | None = None,
@@ -151,9 +152,9 @@ def __init__(
         start_transcript : bool, optional
             Indicates whether to start streaming the Fluent transcript in the client. Defaults to True;
             streaming can be controlled via `transcript.start()` and `transcript.stop()` methods on the session object.
-        case_file_name : str, optional
+        case_file_name : :class:`os.PathLike` or str, optional
             Name of the case file to read into the Fluent session. Defaults to None.
-        case_data_file_name : str, optional
+        case_data_file_name : :class:`os.PathLike` or str, optional
             Name of the case data file. If both case and data files are provided, they are read into the session.
         lightweight_mode : bool, optional
             If True, runs in lightweight mode where mesh settings are read into a background solver session,
@@ -162,9 +163,9 @@ def __init__(
             If True, runs Fluent in Python mode. Defaults to None.
         gpu : bool, optional
             If True, starts Fluent with GPU Solver enabled.
-        cwd : str, optional
+        cwd : :class:`os.PathLike` or str, optional
             Working directory for the Fluent client.
-        fluent_path: str, optional
+        fluent_path: :class:`os.PathLike` or str, optional
             User-specified path for Fluent installation.
         topy :  bool or str, optional
             A flag indicating whether to write equivalent Python journals from provided journal files; can also specify
diff --git a/src/ansys/fluent/core/meshing/meshing_workflow.py b/src/ansys/fluent/core/meshing/meshing_workflow.py
index 2996c37a5231..a35dddc9141d 100644
--- a/src/ansys/fluent/core/meshing/meshing_workflow.py
+++ b/src/ansys/fluent/core/meshing/meshing_workflow.py
@@ -26,7 +26,9 @@
 from __future__ import annotations
 
 from enum import Enum
+import os
 
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.services.datamodel_se import PyMenuGeneric
 from ansys.fluent.core.utils.fluent_version import FluentVersion
 from ansys.fluent.core.workflow import Workflow
@@ -272,7 +274,7 @@ def __init__(
         self,
         workflow: PyMenuGeneric,
         meshing: PyMenuGeneric,
-        file_path: str,
+        file_path: PathType,
         fluent_version: FluentVersion,
     ) -> None:
         """Initialize a ``LoadWorkflow`` instance.
@@ -283,8 +285,8 @@ def __init__(
             Underlying workflow object.
         meshing : PyMenuGeneric
             Meshing object.
-        file_path: str
-            Path to the saved workflow.
+        file_path: os.PathLike[str | bytes] | str | bytes
+            Path to the saved workflow file.
         fluent_version: FluentVersion
             Version of Fluent in this session.
         """
@@ -293,7 +295,7 @@ def __init__(
         )
         self._meshing = meshing
         self._unsubscribe_root_affected_callback()
-        self._load_workflow(file_path=file_path)
+        self._load_workflow(file_path=os.fspath(file_path))
 
 
 class CreateWorkflow(Workflow):
diff --git a/src/ansys/fluent/core/parametric.py b/src/ansys/fluent/core/parametric.py
index fb5c9ae19e79..2fc2889473dc 100644
--- a/src/ansys/fluent/core/parametric.py
+++ b/src/ansys/fluent/core/parametric.py
@@ -51,8 +51,10 @@
 """
 
 from math import ceil
+import os
 from typing import Any, Dict
 
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.launcher.launcher import launch_fluent
 from ansys.fluent.core.utils.execution import asynchronous
 
@@ -60,7 +62,7 @@
 
 
 def convert_design_point_parameter_units(
-    value: Dict[str, float | int | str]
+    value: Dict[str, float | int | str],
 ) -> Dict[str, float | int]:
     """Convert design point parameter units."""
 
@@ -293,13 +295,15 @@ class LocalParametricStudy:
         If the design point is not found.
     """
 
-    def __init__(self, case_filepath: str, base_design_point_name: str = "Base DP"):
+    def __init__(
+        self, case_filepath: PathType, base_design_point_name: str = "Base DP"
+    ):
         """Initialize LocalParametricStudy."""
         from ansys.fluent.core.filereader.casereader import CaseReader
 
-        self.case_filepath = case_filepath
+        self.case_filepath = os.fspath(case_filepath)
         base_design_point = LocalDesignPoint(base_design_point_name)
-        case_reader = CaseReader(case_file_name=case_filepath)
+        case_reader = CaseReader(case_file_name=self.case_filepath)
 
         base_design_point.input_parameters = {
             p.name: p.value for p in case_reader.input_parameters()
diff --git a/src/ansys/fluent/core/services/app_utilities.py b/src/ansys/fluent/core/services/app_utilities.py
index 3f24675a2fac..c19a8e26e514 100644
--- a/src/ansys/fluent/core/services/app_utilities.py
+++ b/src/ansys/fluent/core/services/app_utilities.py
@@ -24,12 +24,14 @@
 
 from dataclasses import dataclass
 from enum import Enum
+import os
 from typing import List, Tuple
 
 import grpc
 
 from ansys.api.fluent.v0 import app_utilities_pb2 as AppUtilitiesProtoModule
 from ansys.api.fluent.v0 import app_utilities_pb2_grpc as AppUtilitiesGrpcModule
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.services.interceptors import (
     BatchInterceptor,
     ErrorStateInterceptor,
@@ -306,7 +308,7 @@ def register_pause_on_solution_events(self, solution_event: SolverEvent) -> int:
                             )
                         ()
                         )
-                    {'#t' if solution_event == SolverEvent.TIMESTEP_ENDED else '#f'}
+                    {"#t" if solution_event == SolverEvent.TIMESTEP_ENDED else "#f"}
                     )
                 (car ids)
                 )
@@ -328,9 +330,9 @@ def exit(self) -> None:
         """Exit."""
         self.scheme.exec(("(exit-server)",))
 
-    def set_working_directory(self, path: str) -> None:
+    def set_working_directory(self, path: PathType) -> None:
         """Change client cortex dir."""
-        self.scheme.eval(f'(syncdir "{path}")')
+        self.scheme.eval(f'(syncdir "{os.fspath(path)}")')
 
 
 class AppUtilities:
@@ -474,10 +476,10 @@ def exit(self) -> None:
         request = AppUtilitiesProtoModule.ExitRequest()
         self.service.exit(request)
 
-    def set_working_directory(self, path: str) -> None:
+    def set_working_directory(self, path: PathType) -> None:
         """Change client cortex dir."""
         request = AppUtilitiesProtoModule.SetWorkingDirectoryRequest()
-        request.path = path
+        request.path = os.fspath(path)
         self.service.set_working_directory(request)
 
 
diff --git a/src/ansys/fluent/core/session.py b/src/ansys/fluent/core/session.py
index 67439b2d6c46..c5fd156c278d 100644
--- a/src/ansys/fluent/core/session.py
+++ b/src/ansys/fluent/core/session.py
@@ -25,12 +25,14 @@
 from enum import Enum
 import json
 import logging
+import os
 from typing import Any, Callable, Dict
 import warnings
 import weakref
 
 from deprecated.sphinx import deprecated
 
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.fluent_connection import FluentConnection
 from ansys.fluent.core.journaling import Journal
 from ansys.fluent.core.pyfluent_warnings import (
@@ -452,15 +454,15 @@ def download(self, file_name: str, local_directory: str | None = None):
         if self._file_transfer_service:
             return self._file_transfer_service.download(file_name, local_directory)
 
-    def chdir(self, path: str) -> None:
+    def chdir(self, path: PathType) -> None:
         """Change Fluent working directory.
 
         Parameters
         ----------
-        path : str
+        path : os.PathLike[str | bytes] | str | bytes
             Path of the directory to change.
         """
-        self._app_utilities.set_working_directory(path)
+        self._app_utilities.set_working_directory(os.fspath(path))
 
     def __enter__(self):
         return self
diff --git a/src/ansys/fluent/core/session_base_meshing.py b/src/ansys/fluent/core/session_base_meshing.py
index dd1772cd7579..a13f415a598a 100644
--- a/src/ansys/fluent/core/session_base_meshing.py
+++ b/src/ansys/fluent/core/session_base_meshing.py
@@ -23,7 +23,9 @@
 """Provides a module to get base Meshing session."""
 
 import logging
+import os
 
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.fluent_connection import FluentConnection
 from ansys.fluent.core.meshing.meshing_workflow import (
     CreateWorkflow,
@@ -177,12 +179,12 @@ def topology_based_meshing_workflow(self, initialize: bool = True):
         )
         return self._current_workflow
 
-    def load_workflow(self, file_path: str):
+    def load_workflow(self, file_path: PathType):
         """Datamodel root of workflow."""
         self._current_workflow = LoadWorkflow(
             _make_datamodel_module(self, "workflow"),
             self.meshing,
-            file_path,
+            os.fspath(file_path),
             self.get_fluent_version(),
         )
         return self._current_workflow
diff --git a/src/ansys/fluent/core/session_pure_meshing.py b/src/ansys/fluent/core/session_pure_meshing.py
index bfe5fcf94b3a..5ad58a9c2f6f 100644
--- a/src/ansys/fluent/core/session_pure_meshing.py
+++ b/src/ansys/fluent/core/session_pure_meshing.py
@@ -23,9 +23,11 @@
 """Module containing class encapsulating Fluent connection."""
 
 import functools
+import os
 from typing import Any, Dict
 
 import ansys.fluent.core as pyfluent
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.data_model_cache import DataModelCache, NameKey
 from ansys.fluent.core.exceptions import BetaFeaturesNotEnabled
 from ansys.fluent.core.fluent_connection import FluentConnection
@@ -164,9 +166,9 @@ def two_dimensional_meshing(self):
         """Get a new 2D meshing workflow."""
         return self._base_meshing.two_dimensional_meshing_workflow()
 
-    def load_workflow(self, file_path: str):
+    def load_workflow(self, file_path: PathType):
         """Load a saved workflow."""
-        return self._base_meshing.load_workflow(file_path=file_path)
+        return self._base_meshing.load_workflow(file_path=os.fspath(file_path))
 
     def create_workflow(self):
         """Create a meshing workflow."""
diff --git a/src/ansys/fluent/core/session_utilities.py b/src/ansys/fluent/core/session_utilities.py
index 37784857c27f..34ec296d91f2 100644
--- a/src/ansys/fluent/core/session_utilities.py
+++ b/src/ansys/fluent/core/session_utilities.py
@@ -25,6 +25,7 @@
 from typing import Any, Dict
 
 import ansys.fluent.core as pyfluent
+from ansys.fluent.core._types import PathType
 from ansys.fluent.core.launcher.container_launcher import DockerLauncher
 from ansys.fluent.core.launcher.launch_options import (
     Dimension,
@@ -74,13 +75,13 @@ def from_install(
         cleanup_on_exit: bool = True,
         dry_run: bool = False,
         start_transcript: bool = True,
-        case_file_name: str | None = None,
-        case_data_file_name: str | None = None,
+        case_file_name: "PathType | None" = None,
+        case_data_file_name: "PathType | None" = None,
         lightweight_mode: bool | None = None,
         py: bool | None = None,
         gpu: bool | None = None,
-        cwd: str | None = None,
-        fluent_path: str | None = None,
+        cwd: "PathType | None" = None,
+        fluent_path: "PathType | None" = None,
         topy: str | list | None = None,
         start_watchdog: bool | None = None,
         file_transfer_service: Any | None = None,
@@ -128,9 +129,9 @@ def from_install(
         start_transcript : bool, optional
             Indicates whether to start streaming the Fluent transcript in the client. Defaults to True;
             streaming can be controlled via `transcript.start()` and `transcript.stop()` methods on the session object.
-        case_file_name : str, optional
+        case_file_name : :class:`os.PathLike` or str, optional
             Name of the case file to read into the Fluent session. Defaults to None.
-        case_data_file_name : str, optional
+        case_data_file_name : :class:`os.PathLike` or str, optional
             Name of the case data file. If both case and data files are provided, they are read into the session.
         lightweight_mode : bool, optional
             If True, runs in lightweight mode where mesh settings are read into a background solver session,
@@ -139,9 +140,9 @@ def from_install(
             If True, runs Fluent in Python mode. Defaults to None.
         gpu : bool, optional
             If True, starts Fluent with GPU Solver enabled.
-        cwd : str, optional
+        cwd : :class:`os.PathLike` or str, optional
             Working directory for the Fluent client.
-        fluent_path: str, optional
+        fluent_path: :class:`os.PathLike` or str, optional
             User-specified path for Fluent installation.
         topy :  bool or str, optional
             A flag indicating whether to write equivalent Python journals from provided journal files; can also specify