diff --git a/Lib/concurrent/futures/_base.py b/Lib/concurrent/futures/_base.py
index cc335d9aa1ea55d..4cf52f87bdd761d 100644
--- a/Lib/concurrent/futures/_base.py
+++ b/Lib/concurrent/futures/_base.py
@@ -310,7 +310,11 @@ def _result_or_cancel(fut, timeout=None):
     try:
         try:
             return (fut.result(timeout), None)
-        except TimeoutError:
+        except TimeoutError as exc:
+            if fut.done():
+                # The future already finished, so this is the callable's own
+                # TimeoutError, not the map() timeout waiting for the future.
+                return (None, exc)
             raise
         except BaseException as exc:
             return (None, exc)
diff --git a/Lib/test/test_concurrent_futures/executor.py b/Lib/test/test_concurrent_futures/executor.py
index 5d9f27c83bf9a81..1b1eac639453687 100644
--- a/Lib/test/test_concurrent_futures/executor.py
+++ b/Lib/test/test_concurrent_futures/executor.py
@@ -29,6 +29,13 @@ def raiser(exception, msg='std'):
     raise exception(msg)
 
 
+# Used in test_map_timeout_from_callable
+def timeout_on_one(x):
+    if x == 1:
+        raise TimeoutError
+    return x
+
+
 class FalseyBoolException(Exception):
     def __bool__(self):
         return False
@@ -87,6 +94,16 @@ def test_map_exception(self):
         self.assertRaises(StopIteration, next, i)
         self.assertRaises(StopIteration, next, i)
 
+    @warnings_helper.ignore_fork_in_thread_deprecation_warnings()
+    def test_map_timeout_from_callable(self):
+        # A TimeoutError from the callable is not the map() timeout.
+        i = self.executor.map(timeout_on_one, [0, 1, 2, 3])
+        self.assertEqual(next(i), 0)
+        self.assertRaises(TimeoutError, next, i)
+        self.assertEqual(next(i), 2)
+        self.assertEqual(next(i), 3)
+        self.assertRaises(StopIteration, next, i)
+
     @warnings_helper.ignore_fork_in_thread_deprecation_warnings()
     @support.requires_resource('walltime')
     def test_map_timeout(self):
diff --git a/Misc/NEWS.d/next/Library/2026-08-15-16-00-00.gh-issue-155852.MapTmo.rst b/Misc/NEWS.d/next/Library/2026-08-15-16-00-00.gh-issue-155852.MapTmo.rst
new file mode 100644
index 000000000000000..57be15bad739238
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-08-15-16-00-00.gh-issue-155852.MapTmo.rst
@@ -0,0 +1,3 @@
+Fix :meth:`concurrent.futures.Executor.map` cancelling the remaining calls when
+the mapped callable raises :exc:`TimeoutError`; such an exception is now
+propagated like any other, without stopping the iteration.