diff --git a/libraries/stdlib/api/js-v1/kotlin.time.kt b/libraries/stdlib/api/js-v1/kotlin.time.kt
index 3afabfe847b..aa17567030e 100644
--- a/libraries/stdlib/api/js-v1/kotlin.time.kt
+++ b/libraries/stdlib/api/js-v1/kotlin.time.kt
@@ -307,10 +307,12 @@ public final inline class Duration : kotlin.Comparable<kotlin.time.Duration> {
 
     @kotlin.time.ExperimentalTime
     @kotlin.Deprecated(message = "Use inWholeMilliseconds property instead.", replaceWith = kotlin.ReplaceWith(expression = "this.inWholeMilliseconds", imports = {}))
+    @kotlin.DeprecatedSinceKotlin(errorSince = "1.8", warningSince = "1.5")
     public final fun toLongMilliseconds(): kotlin.Long
 
     @kotlin.time.ExperimentalTime
     @kotlin.Deprecated(message = "Use inWholeNanoseconds property instead.", replaceWith = kotlin.ReplaceWith(expression = "this.inWholeNanoseconds", imports = {}))
+    @kotlin.DeprecatedSinceKotlin(errorSince = "1.8", warningSince = "1.5")
     public final fun toLongNanoseconds(): kotlin.Long
 
     public open override fun toString(): kotlin.String
diff --git a/libraries/stdlib/api/js/kotlin.time.kt b/libraries/stdlib/api/js/kotlin.time.kt
index 3afabfe847b..aa17567030e 100644
--- a/libraries/stdlib/api/js/kotlin.time.kt
+++ b/libraries/stdlib/api/js/kotlin.time.kt
@@ -307,10 +307,12 @@ public final inline class Duration : kotlin.Comparable<kotlin.time.Duration> {
 
     @kotlin.time.ExperimentalTime
     @kotlin.Deprecated(message = "Use inWholeMilliseconds property instead.", replaceWith = kotlin.ReplaceWith(expression = "this.inWholeMilliseconds", imports = {}))
+    @kotlin.DeprecatedSinceKotlin(errorSince = "1.8", warningSince = "1.5")
     public final fun toLongMilliseconds(): kotlin.Long
 
     @kotlin.time.ExperimentalTime
     @kotlin.Deprecated(message = "Use inWholeNanoseconds property instead.", replaceWith = kotlin.ReplaceWith(expression = "this.inWholeNanoseconds", imports = {}))
+    @kotlin.DeprecatedSinceKotlin(errorSince = "1.8", warningSince = "1.5")
     public final fun toLongNanoseconds(): kotlin.Long
 
     public open override fun toString(): kotlin.String
diff --git a/libraries/stdlib/src/kotlin/time/Duration.kt b/libraries/stdlib/src/kotlin/time/Duration.kt
index e2019f96b69..be30e5b3475 100644
--- a/libraries/stdlib/src/kotlin/time/Duration.kt
+++ b/libraries/stdlib/src/kotlin/time/Duration.kt
@@ -919,6 +919,7 @@ public value class Duration internal constructor(private val rawValue: Long) : C
      */
     @ExperimentalTime
     @Deprecated("Use inWholeNanoseconds property instead.", ReplaceWith("this.inWholeNanoseconds"))
+    @DeprecatedSinceKotlin(warningSince = "1.5", errorSince = "1.8")
     public fun toLongNanoseconds(): Long = inWholeNanoseconds
 
     /**
@@ -930,6 +931,7 @@ public value class Duration internal constructor(private val rawValue: Long) : C
      */
     @ExperimentalTime
     @Deprecated("Use inWholeMilliseconds property instead.", ReplaceWith("this.inWholeMilliseconds"))
+    @DeprecatedSinceKotlin(warningSince = "1.5", errorSince = "1.8")
     public fun toLongMilliseconds(): Long = inWholeMilliseconds
 
     /**