API · SDK · runtime · authentication lifecycle intelligence

Last updated · 28 September 2026

SchemaTrace

Breaking changes, enforcement dates and migration requirements.

ST-2026-252 · SDKs & toolchains

GitHub Actions moves ubuntu-latest from Ubuntu 24.04 to 26.04

GitHub made the Ubuntu 26.04 hosted-runner image generally available and will gradually move ubuntu-latest from Ubuntu 24.04 to 26.04 between 19 October and 19 November 2026.

GitHub Actionsubuntu-latestUbuntu 26.04hosted runnerstoolchain migration

Previous state

The ubuntu-latest hosted-runner label resolves to Ubuntu 24.04.

Current state

During the 19 October–19 November 2026 rollout, ubuntu-latest will gradually resolve to Ubuntu 26.04 on x64 and arm64 hosted runners.

Who needs to care

GitHub Actions workflows that use ubuntu-latest and depend on tools, packages or versions changed or removed in Ubuntu 26.04.

What to do

Test affected workflows on ubuntu-26.04 and pin ubuntu-24.04 temporarily where migration readiness requires it.

What the source does not prove

GitHub proves general availability and the gradual alias-migration window. It does not mean the migration is already complete or establish a general Ubuntu operating-system lifecycle event.

Lifecycle history

Dated event sequence

  1. Ubuntu 26.04 generally available

    GitHub announced full production support and the alias-migration window.

  2. Migration begins

    The ubuntu-latest alias starts moving gradually from 24.04 to 26.04.

  3. Migration window ends

    GitHub's announced gradual migration window ends.

Evidence ledger

First-party sources

  1. 01
    GitHub Changelog — Ubuntu 26 generally available and latest migration

    Official GitHub Actions hosted-runner lifecycle authority · 2026-09-17

    Open official source ↗
  2. 02
    GitHub Actions Runner Images — Ubuntu 26.04 migration tracking issue

    Official GitHub runner-image rollout authority · 2026-09-17

    Open official source ↗