diff --git a/.github/sync-repo-settings.yaml b/.github/sync-repo-settings.yaml
index d85818a..d66f708 100644
--- a/.github/sync-repo-settings.yaml
+++ b/.github/sync-repo-settings.yaml
@@ -23,8 +23,10 @@ branchProtectionRules:
     - 'unit (3.11, upb)'
     - 'unit (3.12, python)'
     - 'unit (3.12, upb)'
-    - 'prerelease (3.12, python)'
-    - 'prerelease (3.12, upb)'
+    - 'unit (3.13, python)'
+    - 'unit (3.13, upb)'
+    - 'prerelease (3.13, python)'
+    - 'prerelease (3.13, upb)'
     - cover
     - OwlBot Post Processor
     - 'cla/google'
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 83d1831..de787df 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -87,7 +87,7 @@ jobs:
     runs-on: ubuntu-22.04
     strategy:
       matrix:
-        python: ['3.12']
+        python: ['3.13']
         variant: ['python', 'upb']
     steps:
       - uses: actions/checkout@v4
diff --git a/noxfile.py b/noxfile.py
index fc9d936..1c16bc5 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -77,7 +77,7 @@ def unit(session, implementation):
 # Only test upb and python implementation backends.
 # As of protobuf 4.x, the "ccp" implementation is not available in the PyPI package as per
 # https://github.com/protocolbuffers/protobuf/tree/main/python#implementation-backends
-@nox.session(python=PYTHON_VERSIONS[-2])
+@nox.session(python=PYTHON_VERSIONS[-1])
 @nox.parametrize("implementation", ["python", "upb"])
 def prerelease_deps(session, implementation):
     """Run the unit test suite against pre-release versions of dependencies."""
diff --git a/setup.py b/setup.py
index e3a5489..d8a430f 100644
--- a/setup.py
+++ b/setup.py
@@ -62,6 +62,7 @@
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",
+        "Programming Language :: Python :: 3.13",
         "Topic :: Software Development :: Code Generators",
         "Topic :: Software Development :: Libraries :: Python Modules",
     ],