diff --git a/CHANGELOG.md b/CHANGELOG.md
index fae3f13..c85dae2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,20 @@
 # Notable Changes in OpenSlide Python
 
+## Version 1.4.3, 2025-12-03
+
+### New features
+
+* Support [free-threaded Python][free-thread]
+
+### Changes
+
+* Drop support for Python 3.9
+* Switch extension module to [multi-phase initialization][multi-phase-init]
+
+[free-thread]: https://docs.python.org/3/howto/free-threading-python.html
+[multi-phase-init]: https://peps.python.org/pep-0489/
+
+
 ## Version 1.4.2, 2025-04-28
 
 ### Changes
diff --git a/openslide/_version.py b/openslide/_version.py
index 2132424..94ae38a 100644
--- a/openslide/_version.py
+++ b/openslide/_version.py
@@ -21,4 +21,4 @@
 This module is an implementation detail.  The package version should be
 obtained from openslide.__version__."""
 
-__version__ = '1.4.2'
+__version__ = '1.4.3'