Python 3.12 End of Life: Dates and How to Upgrade

Python 3.12 reaches end of life on 31 October 2028 and gets security fixes only now. What that means, when to move, and what breaks going to 3.13 or 3.14.

Python 3.12 reaches end of life on 31 October 2028. Until then it receives security fixes only. Its bugfix support ended on 2 April 2025 (the last regular bugfix release, 3.12.10, followed on 8 April), and when the date passes the core team stops releasing fixes of any kind.

The full table for every version is on the Python end-of-life dates page; if you are still on an older version, see Python 3.10 end of life. This guide covers what the 3.12 date means in practice and how to move off it.

Python 3.12 dates

These dates come from endoflife.date, which tracks the Python Developer’s Guide. Every feature release gets about five years of support: roughly two of bugfix releases, then security fixes only. There is no separate long-term-support version.

What “security fixes only” means

For Python itself, very little changes day to day. New 3.12 releases still arrive, but they contain security patches rather than bug fixes. A bug that isn’t a vulnerability will be fixed in newer versions and not in 3.12.

The practical pressure comes from outside: libraries drop old Python versions on their own schedule. Pillow 13, for example, dropped Python 3.10 (see the Pillow security guide). Expect the same to happen to 3.12 well before 2028.

Which version to move to

For most projects, 3.14 is the sensible target. Python 3.15 is worth considering for new work, but libraries often need weeks or months to publish wheels for a new release. See what’s new in Python 3.15 and porting to Python 3.15.

What breaks going from 3.12 to 3.13

The Python 3.13 release notes list the changes. The ones most likely to break an upgrade:

• Removed standard library modules (PEP 594). Nineteen “dead batteries” are gone, including cgi, cgitb, crypt, imghdr, pipes, telnetlib, uu and xdrlib. An import of any of them raises ImportError. The release notes name replacements: shlex.quote() for pipes.quote, email.message.EmailMessage for cgi.parse_header(), and base64 for uu.
• Other removals: lib2to3 and 2to3, tkinter.tix, locale.resetlocale(), and the typing.io and typing.re namespaces.
• locals() semantics (PEP 667). In a function, each call to locals() now returns an independent snapshot, so code that expected earlier results to update will break.
• pathlib.Path.glob(). A pattern ending in ** now returns files as well as directories. Add a trailing slash to keep the old behaviour.
• functools.partial as a method now emits a FutureWarning; wrap it in staticmethod() to keep the old behaviour.

What breaks going from 3.13 to 3.14

• Removed APIs: the asyncio child watcher classes, ast.Num, ast.Str and related aliases, pkgutil.get_loader(), urllib.request.URLopener, and the importlib.abc resource classes (use importlib.resources.abc).
• asyncio.get_event_loop() raises RuntimeError when there is no current loop instead of creating one. Use asyncio.run().
• Deferred annotations (PEP 649). Annotations are no longer evaluated eagerly. Code that reads __annotations__ directly may behave differently; the new annotationlib module lets you choose a format.
• Multiprocessing default. On Unix other than macOS, the default start method is now forkserver rather than fork. Code that relies on forked children inheriting globals will break.

A safe way to upgrade

1. Run your tests on the new version first, with warnings turned on: python -W error -m pytest. Deprecation warnings on 3.12 are removals on 3.13 and 3.14.
2. Search for removed imports before you start. A quick grep for import cgi, telnetlib and pipes finds most of the standard library fallout.
3. Check your dependencies publish wheels for the target version. Packages with compiled extensions are the usual blockers.
4. Move one minor version at a time if the codebase is large, so a failure points at one set of changes.
5. Rebuild anything pinned to 3.12: CI images, containers and lockfiles. A tool like uv can install the new interpreter and create the environment in one step.