Local 'var' is never modified and can be declared as 'val'

Reports local variables declared with the var keyword that are never modified.

Kotlin encourages to declare practically immutable variables using the val keyword, ensuring that their value will never change.

Example:

  fun example() {
      var primeNumbers = listOf(1, 2, 3, 5, 7, 11, 13)
      var fibonacciNumbers = listOf(1, 1, 2, 3, 5, 8, 13)
      print("Same numbers: " + primeNumbers.intersect(fibonacciNumbers))
  }

The quick-fix replaces the var keyword with val:

  fun example() {
      val primeNumbers = listOf(1, 2, 3, 5, 7, 11, 13)
      val fibonacciNumbers = listOf(1, 1, 2, 3, 5, 8, 13)
      print("Same numbers: " + primeNumbers.intersect(fibonacciNumbers))
  }

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

CanBeVal

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | Kotlin | Style issues

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection CanBeVal

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

IntelliJ IDEA 2025.2

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.2, Qodana for JVM 2025.2,

Last modified: 18 September 2025