diff --git a/CHANGELOG.md b/CHANGELOG.md
index d2869cbab..dcafa5347 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,7 @@ Find out more about isort's release policy [here](https://pycqa.github.io/isort/
   - Fixed #1523: in rare cases isort can ignore direct from import if as import is also on same line.
 
   Potentially breaking changes:
+  - Implemented #1540: Officially support Python 3.9 stdlib imports by default.
   - Fixed #1443: Incorrect third vs first party categorization - namespace packages.
   - Fixed #1486: "Google" profile is not quite Google style.
   - Fixed "PyCharm" profile to always add 2 lines to be consistent with what PyCharm "Optimize Imports" does.
diff --git a/isort/stdlibs/py3.py b/isort/stdlibs/py3.py
index 78e0984d5..b7dbcc2cb 100644
--- a/isort/stdlibs/py3.py
+++ b/isort/stdlibs/py3.py
@@ -1,3 +1,3 @@
-from . import py35, py36, py37, py38
+from . import py35, py36, py37, py38, py39
 
-stdlib = py35.stdlib | py36.stdlib | py37.stdlib | py38.stdlib
+stdlib = py35.stdlib | py36.stdlib | py37.stdlib | py38.stdlib | py39.stdlib