diff --git a/changelog/breaking-changes/punctual-platypus.md b/changelog/breaking-changes/punctual-platypus.md
new file mode 100644
index 000000000..8492768c7
--- /dev/null
+++ b/changelog/breaking-changes/punctual-platypus.md
@@ -0,0 +1 @@
+The workflow sandbox now restricts `time.clock_gettime()` and `time.clock_gettime_ns()` at runtime, like `time.time()` and `time.monotonic()`. Calling them from workflow code raises `RestrictedWorkflowAccessError`.
diff --git a/temporalio/worker/workflow_sandbox/_restrictions.py b/temporalio/worker/workflow_sandbox/_restrictions.py
index 9ca5ad4e4..333ad96eb 100644
--- a/temporalio/worker/workflow_sandbox/_restrictions.py
+++ b/temporalio/worker/workflow_sandbox/_restrictions.py
@@ -742,6 +742,10 @@ def _public_callables(parent: Any, *, exclude: set[str] = set()) -> set[str]:
             use={
                 "pthread_getcpuclockid",
                 "get_clock_info",
+                # Not available on every platform (e.g. Windows); matching a
+                # nonexistent attribute is harmless
+                "clock_gettime",
+                "clock_gettime_ns",
                 "localtime",
                 "monotonic",
                 "monotonic_ns",
diff --git a/tests/worker/workflow_sandbox/test_importer.py b/tests/worker/workflow_sandbox/test_importer.py
index 205a8df3b..4ecaa1144 100644
--- a/tests/worker/workflow_sandbox/test_importer.py
+++ b/tests/worker/workflow_sandbox/test_importer.py
@@ -4,6 +4,7 @@
 import subprocess
 import sys
 import textwrap
+import time
 import types
 from typing import Any
 
@@ -40,6 +41,34 @@ def test_workflow_sandbox_importer_path_in_place_division():
             path.exists()
 
 
+@pytest.mark.parametrize(
+    ("function", "args"),
+    [
+        ("time", ""),
+        ("monotonic", ""),
+        ("clock_gettime", "time.CLOCK_REALTIME"),
+        ("clock_gettime_ns", "time.CLOCK_REALTIME"),
+    ],
+    ids=["time", "monotonic", "clock_gettime", "clock_gettime_ns"],
+)
+def test_workflow_sandbox_importer_clock_restricted_at_runtime_only(
+    function: str, args: str
+):
+    if not hasattr(time, function):
+        pytest.skip(f"time.{function} is not available on this platform")
+    call = f"time.{function}({args})"
+    context = RestrictionContext()
+    with Importer(SandboxRestrictions.default, context).applied():
+        import time as sandboxed_time
+
+        # Allowed while the workflow module is being imported
+        eval(call, {"time": sandboxed_time})
+        context.is_runtime = True
+        with pytest.raises(RestrictedWorkflowAccessError) as err:
+            eval(call, {"time": sandboxed_time})
+        assert err.value.qualified_name == f"time.{function}.__call__"
+
+
 @pytest.mark.parametrize("first", ["host", "sandbox"])
 def test_workflow_sandbox_importer_pydantic_constraints(first: str):
     pytest.importorskip("pydantic", minversion="2")
diff --git a/tests/worker/workflow_sandbox/test_runner.py b/tests/worker/workflow_sandbox/test_runner.py
index d357a6872..55ef6384a 100644
--- a/tests/worker/workflow_sandbox/test_runner.py
+++ b/tests/worker/workflow_sandbox/test_runner.py
@@ -201,6 +201,13 @@ async def test_workflow_sandbox_restrictions(client: Client):
         if sys.version_info >= (3, 14):
             invalid_code_to_check.append("import uuid\nuuid.uuid7()")  # type: ignore[reportUnreachable]
 
+        # clock_gettime is not available on every platform (e.g. Windows)
+        if hasattr(time, "clock_gettime"):
+            invalid_code_to_check += [
+                "import time\ntime.clock_gettime(time.CLOCK_REALTIME)",
+                "import time\ntime.clock_gettime_ns(time.CLOCK_REALTIME)",
+            ]
+
         for code in invalid_code_to_check:
             with pytest.raises(WorkflowFailureError) as err:
                 await client.execute_workflow(