diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1f421eb0c3..4d151964e7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,13 @@
+# v0.21.3 (2024-10-02)
+
+## Bugfixes
+- Forward compatibility with Spack 0.23 packages with language dependencies (#45205, #45191)
+- Forward compatibility with `urllib` from Python 3.12.6+ (#46453, #46483)
+- Bump `archspec` to 0.2.5-dev for better aarch64 and Windows support (#42854, #44005,
+  #45721, #46445)
+- Support macOS Sequoia (#45018, #45127, #43862)
+- CI and test maintenance (#42909, #42728, #46711, #41943, #43363)
+
 # v0.21.2 (2024-03-01)
 
 ## Bugfixes
diff --git a/lib/spack/spack/__init__.py b/lib/spack/spack/__init__.py
index 30effe3d84..6fbd19779d 100644
--- a/lib/spack/spack/__init__.py
+++ b/lib/spack/spack/__init__.py
@@ -4,7 +4,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 #: PEP440 canonical <major>.<minor>.<micro>.<devN> string
-__version__ = "0.21.3.dev0"
+__version__ = "0.21.3"
 spack_version = __version__