// guides/lambda-python-3-10-deprecation

Lambda Python 3.10 deprecation: Oct 31, 2026

AWS Lambda deprecates the python3.10 runtime on Oct 31, 2026. Functions keep running, but AWS may stop patching the runtime, and creating new functions is blocked from Jul 29, 2027 and updating them from Aug 31, 2027.

Last checked against AWS documentation: Oct 22, 2026

Key dates for python3.10

Phase	Date	What AWS says happens
Deprecation	Oct 31, 2026	AWS may no longer apply security or other updates; no technical support; you can no longer create or update python3.10 functions in the Lambda console (CLI, SAM and CloudFormation still work).
Block function create	Jul 29, 2027	New python3.10 functions can't be created. Existing ones can still be updated via CLI/SAM/CloudFormation.
Block function update	Aug 31, 2027	Existing python3.10 functions can no longer be updated. After this you can't switch back to the deprecated runtime.

Existing functions keep running: AWS says you can continue to invoke them indefinitely, but they run "as-is" and may hit issues such as certificate expiry. There is no extended-support fee for Lambda.

Find affected functions

AWS lists affected functions in the Health Dashboard (Scheduled changes) and the Trusted Advisor deprecated runtimes check. Or by CLI, in each Region:

aws lambda list-functions --function-version ALL \
  --query "Functions[?Runtime=='python3.10'].[FunctionName,Version]" --output text

Drop --function-version ALL to see only $LATEST. Paste output into the checker.

Upgrading to Python 3.14

python3.14 is supported until Jun 30, 2029 (create blocked Jul 31, 2029, update blocked Aug 31, 2029).
python3.10 runs on Amazon Linux 2; python3.12 and later run on Amazon Linux 2023. Rebuild native dependencies and layers for the new OS rather than reusing AL2 builds.
Python 3.12 removed distutils; Python 3.13 removed several old standard-library modules (cgi, crypt, telnetlib, ...).
Change the runtime identifier (Runtime: python3.14 in SAM/CloudFormation, runtime = "python3.14" in Terraform). Container-image functions need a new base image instead.
AWS recommends testing first and using versions and aliases for rollback.

Full list: what breaks moving off python3.10. Python 3.11 is on AL2 too and is deprecated Jun 30, 2027, so it is a short stop.

Sources

FAQ

When is Lambda python3.10 deprecated?

Oct 31, 2026. Function creation is blocked Jul 29, 2027 and function updates Aug 31, 2027, per the AWS Lambda runtimes table.

Will my python3.10 functions stop working?

No. AWS says you can continue to invoke them indefinitely, but they no longer get security updates or technical support and may break over time.

Can I still deploy python3.10 after Oct 31, 2026?

Not from the Lambda console. Through the AWS CLI, SAM or CloudFormation you can still create functions until Jul 29, 2027 and update them until Aug 31, 2027.

What should I upgrade to?

python3.14, supported until Jun 30, 2029. It runs on Amazon Linux 2023 instead of Amazon Linux 2, so rebuild native dependencies.