diff --git a/pyiceberg/catalog/rest/__init__.py b/pyiceberg/catalog/rest/__init__.py
index d9f0ced811..9ae6f489c2 100644
--- a/pyiceberg/catalog/rest/__init__.py
+++ b/pyiceberg/catalog/rest/__init__.py
@@ -361,6 +361,11 @@ def _retry_hook(retry_state: RetryCallState) -> None:
     rest_catalog._refresh_token()  # pylint: disable=protected-access
 
 
+def _user_agent() -> str:
+    """Return the User-Agent recommended by the REST catalog spec, for example `pyiceberg/0.11.0 (cpython 3.11.4)`."""
+    return f"pyiceberg/{__version__} ({platform.python_implementation().lower()} {platform.python_version()})"
+
+
 _RETRY_ARGS = {
     "retry": retry_if_exception_type((AuthorizationExpiredError, UnauthorizedError)),
     "stop": stop_after_attempt(2),
@@ -1232,9 +1237,7 @@ def _config_headers(self, session: Session) -> None:
         header_properties = get_header_properties(self.properties)
         session.headers.update(header_properties)
         session.headers["Content-type"] = "application/json"
-        session.headers["User-Agent"] = (
-            f"pyiceberg/{__version__} ({platform.python_implementation().lower()} {platform.python_version()})"
-        )
+        session.headers["User-Agent"] = _user_agent()
         session.headers["X-Client-Version"] = f"PyIceberg {__version__}"
         session.headers.setdefault("X-Iceberg-Access-Delegation", ACCESS_DELEGATION_DEFAULT)
 
diff --git a/pyiceberg/io/fsspec.py b/pyiceberg/io/fsspec.py
index 49f10b1310..e27dacdd2c 100644
--- a/pyiceberg/io/fsspec.py
+++ b/pyiceberg/io/fsspec.py
@@ -38,6 +38,7 @@
 from typing_extensions import override
 
 from pyiceberg.catalog import TOKEN, URI
+from pyiceberg.catalog.rest import _user_agent
 from pyiceberg.catalog.rest.auth import AUTH_MANAGER
 from pyiceberg.exceptions import SignError
 from pyiceberg.io import (
@@ -141,6 +142,7 @@ def __call__(self, request: "AWSRequest", operation_name: str | None = None, **_
             signer_headers["Authorization"] = auth_header
 
         signer_headers.update(get_header_properties(self.properties))
+        signer_headers["User-Agent"] = _user_agent()
 
         signer_body = {
             "method": request.method,
diff --git a/tests/io/test_fsspec.py b/tests/io/test_fsspec.py
index 66bb319d49..e7b2c82687 100644
--- a/tests/io/test_fsspec.py
+++ b/tests/io/test_fsspec.py
@@ -32,6 +32,7 @@
 from fsspec.spec import AbstractFileSystem
 from requests_mock import Mocker
 
+from pyiceberg.catalog.rest import _user_agent
 from pyiceberg.catalog.rest.auth import AUTH_MANAGER
 from pyiceberg.exceptions import SignError
 from pyiceberg.io import fsspec
@@ -1028,6 +1029,7 @@ def test_s3v4_rest_signer(requests_mock: Mocker) -> None:
         "x-amz-content-sha256": "UNSIGNED-PAYLOAD",
         "X-Custom-Header": "value",
     }
+    assert requests_mock.last_request.headers["User-Agent"] == _user_agent()
 
 
 @pytest.mark.s3