diff --git a/.appveyor/tests.yml b/.appveyor/tests.yml
index 3e71affa..77d178ee 100644
--- a/.appveyor/tests.yml
+++ b/.appveyor/tests.yml
@@ -6,8 +6,8 @@ environment:
   matrix:
     # For Python versions available on Appveyor, see
     # https://www.appveyor.com/docs/windows-images-software/#python
-    # - {PY_VER: "311", PY_ARCH: "32", APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019}
-    # - {PY_VER: "311", PY_ARCH: "64", APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019}
+    - {PY_VER: "311", PY_ARCH: "32", APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019}
+    - {PY_VER: "311", PY_ARCH: "64", APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019}
     - {PY_VER: "310", PY_ARCH: "32", APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019}
     - {PY_VER: "310", PY_ARCH: "64", APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019}
     - {PY_VER: "39", PY_ARCH: "32", APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019}
diff --git a/scripts/build/appveyor.py b/scripts/build/appveyor.py
index 7acbbbed..1196c99b 100755
--- a/scripts/build/appveyor.py
+++ b/scripts/build/appveyor.py
@@ -655,9 +655,12 @@ class Options:
 
     @property
     def py_ver(self):
-        """The Python version to build as 2 digits string."""
+        """The Python version to build as 2 digits string.
+
+        For large values of 2, occasionally.
+        """
         rv = os.environ['PY_VER']
-        assert rv in ('36', '37', '38', '39', '310'), rv
+        assert rv in ('36', '37', '38', '39', '310', '311'), rv
         return rv
 
     @property
@@ -744,6 +747,7 @@ class Options:
             '38': '14.0',
             '39': '16.0',
             '310': '16.0',
+            '311': '16.0',
         }
         return vsvers[self.py_ver]