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 When maintaining projects over time, you might find yourself using an outdated version that no longer receives security patches or bug fixes.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

6. Kotlin 2.x Series Detailed Release History

Kotlin 2.3.x (Beta) – Next-Generation Features Preview

Kotlin 2.2.x (Current Stable) – K2 Compiler Maturity

Kotlin 2.1.x (EOL) – K2 Compiler Improvements

Kotlin 2.0.x (EOL) – K2 Compiler Official Release

7. Kotlin 1.x Series Version History

Kotlin 1.9.x (EOL) – Kotlin/Native Stabilization

Kotlin 1.8.x (EOL) – Web Development Enhancement

Kotlin 1.7.x (EOL) – K2 Compiler Alpha

Kotlin 1.6.x (EOL) – API Compatibility Enhancement

Kotlin 1.5.x (EOL) – JVM Record Support

Kotlin 1.4.x (EOL) – IR Backend Introduction

Kotlin 1.3.x (EOL) – Coroutines Stabilization

Kotlin 1.2.x (EOL) – Multiplatform Experimentation

Kotlin 1.1.x (EOL) – Coroutines Introduction

Kotlin 1.0.x (EOL) – First 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

Planned Update Timing

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

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:

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! 🙂