diff --git a/CHANGES.md b/CHANGES.md
index 35024de724d..db519ac6bbc 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,11 @@
 # Change Log
 
+## Unreleased
+
+### _Black_
+
+- Fixed Python 3.10 support on platforms without ProcessPoolExecutor (#2631)
+
 ## 21.11b1
 
 ### _Black_
diff --git a/src/black/__init__.py b/src/black/__init__.py
index a5ddec91221..aa7970cfd6c 100644
--- a/src/black/__init__.py
+++ b/src/black/__init__.py
@@ -687,7 +687,7 @@ def reformat_many(
         worker_count = min(worker_count, 60)
     try:
         executor = ProcessPoolExecutor(max_workers=worker_count)
-    except (ImportError, OSError):
+    except (ImportError, NotImplementedError, OSError):
         # we arrive here if the underlying system does not support multi-processing
         # like in AWS Lambda or Termux, in which case we gracefully fallback to
         # a ThreadPoolExecutor with just a single worker (more workers would not do us