AWS Lambda Deprecates Python 3.10 Runtime Effective October 31, 2026
AWS has announced the deprecation of the Python 3.10 runtime for Lambda functions, with support officially ending on October 31, 2026.
AWS Lambda deprecates Python 3.10 on October 31, 2026, matching its upstream end of life date. AWS will block creating new python3.10 functions on July 29, 2027, and block updates to existing functions on August 31, 2027.
The runtime runs on Amazon Linux 2. Until October 31, 2026, Python 3.10 receives language runtime patches and patches for critical and selected important Amazon Linux 2 security issues. Once deprecated, already deployed functions continue to run without patches, and invocations are not blocked.
Because third-party trackers may list different dates, you should check the AWS runtime page for your planning. You can use the AWS CLI to list affected functions per Region across all versions:
aws lambda list-functions --function-version ALL --query "Functions[?Runtime=='python3.10'].[FunctionName,Version]" --output text
For target runtimes, Python 3.11 also runs on Amazon Linux 2, deprecating on June 30, 2027, with create-blocking on July 29, 2027 and update-blocking on August 31, 2027. Moving to Python 3.11 only buys about eight months before you face another migration.
Python 3.12 runs on Amazon Linux 2023 with a deprecation date of October 31, 2028. Python 3.13 also runs on Amazon Linux 2023, with end of support listed as June 30, 2029 in a third-party table. Migrating to Python 3.12 or 3.13 requires rebuilding native dependencies and Lambda layers against the newer operating system. AWS notifies customers via email and the Personal Health Dashboard, giving a 180-day notice period.