If you’ve been developing Android apps, you’ve probably wondered, “Is the Kotlin version I’m using still supported?” When maintaining projects over time, you might find yourself using an outdated version that no longer receives security patches or bug fixes.
This guide provides a comprehensive overview of Kotlin’s version support policies and the EOL (End of Life) and EOS (End of Support) schedules for each version. After reading this, you’ll be able to clearly determine whether your current Kotlin version is safe and when you should consider updating.
1. What is Kotlin? – A Modern Multiplatform Programming Language
Kotlin is a statically typed, cross-platform programming language developed by JetBrains. Since the first stable version 1.0 was released on February 15, 2016, Kotlin has grown rapidly, especially after Google announced it as the preferred language for Android app development on May 7, 2019.
Key features of Kotlin include:
- Full Java Interoperability: 100% compatible with existing Java code, allowing Java and Kotlin to coexist in the same project
- Concise and Expressive Syntax: Requires less boilerplate code than Java, increasing productivity
- Multiplatform Support: Compiles to JVM, JavaScript, and Native code, enabling use across Android, iOS, web, servers, and more
- Null Safety: Includes nullability in the type system, significantly reducing NullPointerException occurrences
As of 2025, over 60% of professional Android developers use Kotlin, and statistics show that Android apps written in Kotlin are 20% less likely to crash compared to those written in Java.
2. Kotlin’s License Policy – Free and Open Source
Kotlin is a completely free, open-source project distributed under the Apache License 2.0. This license is friendly to both commercial and open-source projects, providing the following freedoms:
- Free to use for personal and commercial purposes
- Source code can be modified and distributed
- Includes patent protection clauses
- Only requires maintaining license notices and copyright statements
Kotlin’s source code is developed publicly on GitHub, led by the JetBrains team with contributions from Google and the community. Since becoming open source in February 2012, it has been provided free of charge and will remain free indefinitely.
3. Understanding Kotlin’s Release Policy and Versioning System
Starting with Kotlin 2.0.0, JetBrains introduced a more structured release policy. Kotlin currently provides three types of releases:
Language Releases
Version format: 2.x.0
Major language changes and tooling updates, released every 6 months. Includes new language features, API changes, and significant performance improvements.
Tooling Releases
Version format: 2.x.20
Released between language releases, containing tooling updates, performance improvements, and bug fixes. Released 3 months after the corresponding language release.
Bug Fix Releases
Version format: 2.x.yz
Contains bug fixes for tooling releases, with no fixed schedule—released as needed.
Before each release, several EAP (Early Access Preview) versions are released for users to test new features.
4. Kotlin’s Support Policy – Which Versions Are Safe?
While Kotlin’s support policy isn’t clearly documented, generally only the latest version receives active development and bug and security fixes. According to official documentation, the following principles apply:
- Active Support: Only the latest stable version receives new feature development and all bug/security patches
- API Compatibility Support: Development is supported for three previous API versions along with the current stable one
- Backward Compatibility Guarantee: All versions since Kotlin 1.0 maintain long-term backward compatibility
As of October 2025, with Kotlin 2.2 being the latest version, development is supported for four API versions: 2.2, 2.1, 2.0, and 1.9. However, since bug fixes and security patches are provided only for the latest version, using the most recent version is recommended.
5. Complete Kotlin Version Release Status (As of October 23, 2025)
Major Version Support Status Summary
| Version Series | First Release | Latest Patch | Latest Patch Date | Support Status |
|---|---|---|---|---|
| 2.3.x | Oct 07, 2025 | 2.3.0-Beta1 | Oct 07, 2025 | 🔧 Beta |
| 2.2.x | Jun 23, 2025 | 2.2.20 | Sep 10, 2025 | ✅ Supported |
| 2.1.x | Nov 27, 2024 | 2.1.21 | May 13, 2025 | ⚠️ EOL |
| 2.0.x | May 21, 2024 | 2.0.21 | Oct 10, 2024 | ⚠️ EOL |
| 1.9.x | Jul 06, 2023 | 1.9.25 | Jul 19, 2024 | ⚠️ EOL |
| 1.8.x | Dec 28, 2022 | 1.8.22 | Jun 08, 2023 | ⚠️ EOL |
| 1.7.x | Jun 09, 2022 | 1.7.22 | Nov 28, 2022 | ⚠️ EOL |
| 1.6.x | Nov 16, 2021 | 1.6.21 | Apr 20, 2022 | ⚠️ EOL |
| 1.5.x | May 05, 2021 | 1.5.32 | Nov 29, 2021 | ⚠️ EOL |
| 1.4.x | Aug 14, 2020 | 1.4.32 | Mar 30, 2021 | ⚠️ EOL |
| 1.3.x | Oct 29, 2018 | 1.3.72 | Apr 15, 2020 | ⚠️ EOL |
| 1.2.x | Nov 28, 2017 | 1.2.71 | Sep 24, 2018 | ⚠️ EOL |
| 1.1.x | Mar 01, 2017 | 1.1.61 | Nov 24, 2017 | ⚠️ EOL |
| 1.0.x | Feb 15, 2016 | 1.0.7 | Mar 15, 2017 | ⚠️ EOL |
6. Kotlin 2.x Series Detailed Release History
Kotlin 2.3.x (Beta) – Next-Generation Features Preview
| Version | Release Date | Release Type | Key Features |
|---|---|---|---|
| 2.3.0-Beta1 | Oct 07, 2025 | Beta | Nested type aliases stabilization, Unused return value checker |
Kotlin 2.2.x (Current Stable) – K2 Compiler Maturity
| Version | Release Date | Release Type | Key Features |
|---|---|---|---|
| 2.2.21-RC2 | Oct 16, 2025 | RC | – |
| 2.2.20 | Sep 10, 2025 | Tooling Release | Kotlin/Wasm Beta, Swift export default support |
| 2.2.20-RC2 | Sep 01, 2025 | RC | – |
| 2.2.20-RC | Aug 19, 2025 | RC | – |
| 2.2.10 | Aug 14, 2025 | Bug Fix | Bug fixes and stability improvements |
| 2.2.10-RC2 | Aug 06, 2025 | RC | – |
| 2.2.20-Beta2 | Jul 29, 2025 | Beta | – |
| 2.2.10-RC | Jul 18, 2025 | RC | – |
| 2.2.20-Beta1 | Jul 10, 2025 | Beta | – |
| 2.2.0 | Jun 23, 2025 | Language Release | Context parameters preview, Guard conditions stabilization |
| 2.2.0-RC3 | Jun 16, 2025 | RC | – |
| 2.2.0-RC2 | Jun 04, 2025 | RC | – |
| 2.2.0-RC | May 16, 2025 | RC | – |
| 2.2.0-Beta2 | Apr 30, 2025 | Beta | – |
| 2.2.0-Beta1 | Apr 15, 2025 | Beta | – |
Kotlin 2.1.x (EOL) – K2 Compiler Improvements
| Version | Release Date | Release Type | Key Features |
|---|---|---|---|
| 2.1.21 | May 13, 2025 | Bug Fix | Xcode 16.3 support |
| 2.1.21-RC2 | May 01, 2025 | RC | – |
| 2.1.21-RC | Apr 17, 2025 | RC | – |
| 2.1.20 | Mar 20, 2025 | Tooling Release | K2 kapt default enabled, Kotlin/Native inlining optimization |
| 2.1.20-RC3 | Mar 14, 2025 | RC | – |
| 2.1.20-RC2 | Mar 06, 2025 | RC | – |
| 2.1.20-RC | Feb 19, 2025 | RC | – |
| 2.1.20-Beta2 | Jan 29, 2025 | Beta | – |
| 2.1.10 | Jan 27, 2025 | Bug Fix | Bug fixes |
| 2.1.10-RC2 | Jan 20, 2025 | RC | – |
| 2.1.10-RC | Jan 09, 2025 | RC | – |
| 2.1.20-Beta1 | Dec 19, 2024 | Beta | – |
| 2.1.0 | Nov 27, 2024 | Language Release | Guard conditions preview, Kotlin/Wasm incremental compilation |
| 2.1.0-RC2 | Nov 18, 2024 | RC | – |
| 2.1.0-RC | Nov 04, 2024 | RC | – |
| 2.1.0-Beta2 | Oct 14, 2024 | Beta | – |
| 2.1.0-Beta1 | Sep 17, 2024 | Beta | – |
Kotlin 2.0.x (EOL) – K2 Compiler Official Release
| Version | Release Date | Key Features |
|---|---|---|
| 2.0.21 | Oct 10, 2024 | Final patch release |
| 2.0.20 | Aug 22, 2024 | Tooling release |
| 2.0.10 | Aug 05, 2024 | Bug fixes |
| 2.0.0 | May 21, 2024 | K2 compiler official release, Significant compilation speed improvements |
7. Kotlin 1.x Series Version History
Kotlin 1.9.x (EOL) – Kotlin/Native Stabilization
| Version | Release Date | Key Features |
|---|---|---|
| 1.9.25 | Jul 19, 2024 | Final patch release |
| 1.9.24 | May 07, 2024 | Bug fixes |
| 1.9.23 | Mar 07, 2024 | Bug fixes |
| 1.9.22 | Jan 18, 2024 | Bug fixes |
| 1.9.21 | Nov 23, 2023 | Bug fixes |
| 1.9.20 | Nov 01, 2023 | Kotlin/Native declared stable |
| 1.9.10 | Aug 23, 2023 | Bug fixes |
| 1.9.0 | Jul 06, 2023 | K2 compiler beta, Kotlin/Wasm alpha |
Kotlin 1.8.x (EOL) – Web Development Enhancement
| Version | Release Date | Key Features |
|---|---|---|
| 1.8.22 | Jun 08, 2023 | Final patch release |
| 1.8.21 | Apr 25, 2023 | Bug fixes |
| 1.8.20 | Apr 03, 2023 | Incremental release |
| 1.8.10 | Jan 19, 2023 | Bug fixes |
| 1.8.0 | Dec 28, 2022 | Kotlin/JS IR backend stabilization |
Kotlin 1.7.x (EOL) – K2 Compiler Alpha
| Version | Release Date | Key Features |
|---|---|---|
| 1.7.22 | Nov 28, 2022 | Final patch release |
| 1.7.21 | Nov 09, 2022 | Bug fixes |
| 1.7.20 | Sep 29, 2022 | Incremental release, ..< operator introduction |
| 1.7.10 | Jul 07, 2022 | Bug fixes |
| 1.7.0 | Jun 09, 2022 | K2 compiler alpha, Builder type inference improvements |
Kotlin 1.6.x (EOL) – API Compatibility Enhancement
| Version | Release Date | Key Features |
|---|---|---|
| 1.6.21 | Apr 20, 2022 | Final patch release |
| 1.6.20 | Apr 04, 2022 | Incremental release |
| 1.6.10 | Dec 14, 2021 | Bug fixes |
| 1.6.0 | Nov 16, 2021 | Annotation instantiation stabilization, New memory manager |
Kotlin 1.5.x (EOL) – JVM Record Support
| Version | Release Date | Key Features |
|---|---|---|
| 1.5.32 | Nov 29, 2021 | Final patch release |
| 1.5.31 | Sep 20, 2021 | Bug fixes |
| 1.5.30 | Aug 23, 2021 | Incremental release |
| 1.5.21 | Jul 13, 2021 | Bug fixes |
| 1.5.20 | Jun 24, 2021 | Incremental release |
| 1.5.10 | May 24, 2021 | Bug fixes |
| 1.5.0 | May 05, 2021 | JVM Record class support stabilization, IR-based JVM backend |
Kotlin 1.4.x (EOL) – IR Backend Introduction
| Version | Release Date | Key Features |
|---|---|---|
| 1.4.32 | Mar 30, 2021 | Final patch release |
| 1.4.31 | Feb 25, 2021 | Bug fixes |
| 1.4.30 | Feb 03, 2021 | Incremental release |
| 1.4.21 | Dec 07, 2020 | Bug fixes |
| 1.4.20 | Nov 23, 2020 | Incremental release |
| 1.4.10 | Sep 07, 2020 | Bug fixes |
| 1.4.0 | Aug 14, 2020 | New Kotlin/JS IR backend |
Kotlin 1.3.x (EOL) – Coroutines Stabilization
| Version | Release Date | Key Features |
|---|---|---|
| 1.3.72 | Apr 15, 2020 | Final patch release |
| 1.3.71 | Mar 18, 2020 | Bug fixes |
| 1.3.70 | Mar 03, 2020 | Incremental release |
| 1.3.61 | Nov 28, 2019 | Bug fixes |
| 1.3.60 | Nov 14, 2019 | Incremental release |
| 1.3.50 | Aug 20, 2019 | Incremental release |
| 1.3.41 | Jul 09, 2019 | Bug fixes |
| 1.3.40 | Jun 26, 2019 | Incremental release |
| 1.3.31 | May 07, 2019 | Bug fixes |
| 1.3.30 | Apr 23, 2019 | Incremental release |
| 1.3.21 | Feb 06, 2019 | Bug fixes |
| 1.3.20 | Jan 24, 2019 | Incremental release |
| 1.3.11 | Dec 04, 2018 | Bug fixes |
| 1.3.10 | Nov 27, 2018 | Incremental release |
| 1.3.0 | Oct 29, 2018 | Coroutines stabilization, Kotlin/Native beta |
Kotlin 1.2.x (EOL) – Multiplatform Experimentation
| Version | Release Date | Key Features |
|---|---|---|
| 1.2.71 | Sep 24, 2018 | Final patch release |
| 1.2.70 | Aug 28, 2018 | Incremental release |
| 1.2.61 | Aug 13, 2018 | Bug fixes |
| 1.2.60 | Aug 02, 2018 | Incremental release |
| 1.2.51 | Jun 19, 2018 | Bug fixes |
| 1.2.50 | Jun 07, 2018 | Incremental release |
| 1.2.41 | May 03, 2018 | Bug fixes |
| 1.2.40 | Apr 27, 2018 | Incremental release |
| 1.2.31 | Mar 22, 2018 | Bug fixes |
| 1.2.30 | Mar 01, 2018 | Incremental release |
| 1.2.21 | Jan 30, 2018 | Bug fixes |
| 1.2.20 | Jan 17, 2018 | Incremental release |
| 1.2.10 | Dec 19, 2017 | Bug fixes |
| 1.2.0 | Nov 28, 2017 | Experimental multiplatform project support |
Kotlin 1.1.x (EOL) – Coroutines Introduction
| Version | Release Date | Key Features |
|---|---|---|
| 1.1.61 | Nov 24, 2017 | Final patch release |
| 1.1.60 | Nov 16, 2017 | Incremental release |
| 1.1.51 | Sep 21, 2017 | Bug fixes |
| 1.1.50 | Aug 31, 2017 | Incremental release |
| 1.1.4-3 | Aug 21, 2017 | Bug fixes |
| 1.1.4-2 | Aug 16, 2017 | Bug fixes |
| 1.1.4 | Aug 15, 2017 | Bug fixes |
| 1.1.3-2 | Jul 14, 2017 | Bug fixes |
| 1.1.3 | Jun 23, 2017 | Incremental release |
| 1.1.2-5 | May 29, 2017 | Bug fixes |
| 1.1.2-4 | May 23, 2017 | Bug fixes |
| 1.1.2-3 | May 19, 2017 | Bug fixes |
| 1.1.2-2 | May 16, 2017 | Bug fixes |
| 1.1.2 | Apr 25, 2017 | Incremental release |
| 1.1.1 | Mar 14, 2017 | Bug fixes |
| 1.1.0 | Mar 01, 2017 | Experimental coroutines support, JavaScript target |
Kotlin 1.0.x (EOL) – First Stable Release
| Version | Release Date | Key Features |
|---|---|---|
| 1.0.7 | Mar 15, 2017 | Final patch release |
| 1.0.6 | Dec 27, 2016 | Bug fixes |
| 1.0.5-2 | Nov 09, 2016 | Bug fixes |
| 1.0.5 | Nov 08, 2016 | Bug fixes |
| 1.0.4 | Sep 22, 2016 | Bug fixes |
| 1.0.3 | Jun 30, 2016 | Bug fixes |
| 1.0.2 | May 13, 2016 | Bug fixes |
| 1.0.1-2 | Mar 22, 2016 | Bug fixes |
| 1.0.1-1 | Mar 18, 2016 | Bug fixes |
| 1.0.1 | Mar 16, 2016 | Bug fixes |
| 1.0.0 | Feb 15, 2016 | First official stable release |
8. Key Features by Version and Upgrade Considerations
Kotlin 2.x Series – The K2 Compiler Era
Kotlin 2.0 represents one of the most significant milestones in Kotlin’s history. The completely rewritten K2 compiler was officially introduced, dramatically improving compilation speed. Starting with Kotlin 2.0.0, a new release policy was introduced with language releases every 6 months, tooling releases every 3 months, and bug fix releases as needed.
Key Changes:
- Official K2 compiler release with significantly improved compilation performance
- More accurate type inference
- Enhanced IDE support (K2 mode enabled by default in IntelliJ IDEA 2025.1)
Kotlin 1.9.x – Stability and Performance Improvements
Kotlin/Native was declared stable in Kotlin 1.9.20. This means native platform support, including iOS app development, reached a level safe for production environments.
Kotlin 1.8.x – Web Development Enhancement
The Kotlin/JS IR backend was stabilized in Kotlin 1.8. This made JavaScript targeting more stable and efficient.
Kotlin 1.5.x – Enhanced JVM Compatibility
Bidirectional interoperability support with JVM Record classes introduced in Java 16 was stabilized in Kotlin 1.5. This enables natural use of the latest Java features in Kotlin.
9. Version Management Strategy in Practice – When to Update?
Immediate Update Required
| Situation | Recommended Action |
|---|---|
| Security vulnerability discovered | Update to latest stable version immediately |
| Critical bugs | Update to version with fix |
| Using EOL version (1.8 or earlier) | Update to at least 1.9, preferably 2.2 |
Planned Update Timing
| Timing | Update Strategy |
|---|---|
| 2-3 months after new language release | Use stable version with initial bugs resolved |
| Major libraries support new version | Update after verifying dependency compatibility |
| Project refactoring period | Proceed with other major changes |
Updating Kotlin Version in Gradle
// build.gradle.kts (Kotlin DSL)
plugins {
kotlin("jvm") version "2.2.20"
// Or for Android
// kotlin("android") version "2.2.20"
// For Multiplatform
// kotlin("multiplatform") version "2.2.20"
}
// build.gradle (Groovy)
plugins {
id 'org.jetbrains.kotlin.jvm' version '2.2.20'
// Or for Android
// id 'org.jetbrains.kotlin.android' version '2.2.20'
}
10. Migration Considerations and Tips
Compatibility Checklist
| Checklist | Verification |
|---|---|
| Dependency libraries | Update kotlinx.coroutines, kotlinx.serialization, etc. together |
| IDE plugins | Check Kotlin plugin version in IntelliJ IDEA/Android Studio |
| Build tools | Verify minimum required Gradle/Maven version |
| Platform compatibility | Check Android Gradle Plugin, JVM version, etc. |
Automatic Updates in IntelliJ IDEA and Android Studio
IntelliJ IDEA and Android Studio automatically suggest updates when new Kotlin releases are available. Accepting the IDE’s suggestion automatically updates the Kotlin plugin.
Check update settings: Tools | Kotlin | Configure Plugin Updates
Using Migration Tools
When upgrading major versions, you can use the Kotlin plugin’s migration tools. These tools automatically identify deprecated APIs and help replace them with new ones.
11. Additional Resources and Official Information Sources
Reference these official resources when deciding on or planning Kotlin version updates:
| Resource | URL | Purpose |
|---|---|---|
| Kotlin Official Releases | https://kotlinlang.org/docs/releases.html | Latest release info and update guides |
| Kotlin GitHub Repository | https://github.com/JetBrains/kotlin | Source code and issue tracker |
| Kotlin Security Policy | https://kotlinlang.org/docs/security.html | Security announcements |
| endoflife.date – Kotlin | https://endoflife.date/kotlin | EOL/EOS schedule tracking |
| Kotlin Blog | https://blog.jetbrains.com/kotlin/ | Release announcements and details |
| GitHub ChangeLog | https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md | Detailed version changes |
Kotlin version management is straightforward. Using the latest version is safest, and since only the latest version receives bug fixes and security patches, regular updates are essential.
Recommendations as of October 23, 2025:
- Kotlin 2.2.20 strongly recommended (latest stable version with full support)
- Using Kotlin 2.1.x or earlier → Upgrade to 2.2 needed
- Using Kotlin 1.x series → Mandatory upgrade for security and performance improvements
The K2 compiler in Kotlin 2.x series offers much faster compilation speeds and improved development experience, so consider upgrading to 2.2 soon.
For project stability and security, regularly check the official release page and subscribe to the Kotlin Newsletter for new version announcements. May your projects always run in the latest, secure environment! 🙂