Kotlin 2.3 End of Life
Support dates and upgrade guidance — rebuilt from live data.
End of Life
Kotlin 2.3 reached end of life on 3 Jun 2026. It no longer receives security fixes.
67 days without security patches
Recommended action: upgrade to Kotlin 2.4. Check your versionkotlinc-native -version
Support timeline
Official dates from the Kotlin release process.
| Milestone | Date | Status |
|---|---|---|
| Initial release | 16 Dec 2025 | — |
| End of life | 3 Jun 2026 | 0.2 years ago |
| Latest release | 2.3.21 · 23 Apr 2026 | final |
Where to go from 2.3
Recommended target: Kotlin 2.4.
The newest actively supported branch is Kotlin 2.4 (latest release 2.4.10).
Frequently asked questions
Is Kotlin 2.3 still safe to use?
Kotlin 2.3 reached end of life on 3 Jun 2026, 67 days ago, and is no longer covered by standard support. Running it means no guaranteed security fixes.
Can I still download Kotlin 2.3?
Yes — the final release (2.3.21) generally remains available from vendor archives and OS package mirrors, but installing it means running software with known, unpatched vulnerabilities.
What should I upgrade Kotlin 2.3 to?
Upgrade to Kotlin 2.4, the newest actively supported branch.