diff --git a/libraries/stdlib/common/src/kotlin/TextH.kt b/libraries/stdlib/common/src/kotlin/TextH.kt
index 1c18252e0eb..b5a4009e5d4 100644
--- a/libraries/stdlib/common/src/kotlin/TextH.kt
+++ b/libraries/stdlib/common/src/kotlin/TextH.kt
@@ -175,6 +175,10 @@ expect fun String?.equals(other: String?, ignoreCase: Boolean = false): Boolean
 expect fun String.compareTo(other: String, ignoreCase: Boolean = false): Int
 
 
+public expect fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boolean
+public expect fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolean = false): Boolean
+public expect fun String.endsWith(suffix: String, ignoreCase: Boolean = false): Boolean
+
 // From stringsCode.kt
 
 internal expect fun String.nativeIndexOf(ch: Char, fromIndex: Int): Int
diff --git a/libraries/stdlib/js/src/kotlin/stringsCode.kt b/libraries/stdlib/js/src/kotlin/stringsCode.kt
index 8012a902aa7..b4856deee5d 100644
--- a/libraries/stdlib/js/src/kotlin/stringsCode.kt
+++ b/libraries/stdlib/js/src/kotlin/stringsCode.kt
@@ -16,7 +16,8 @@ internal actual inline fun String.nativeLastIndexOf(ch: Char, fromIndex: Int): I
 /**
  * Returns `true` if this string starts with the specified prefix.
  */
-public fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boolean {
+@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
+public actual fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boolean {
     if (!ignoreCase)
         return nativeStartsWith(prefix, 0)
     else
@@ -26,7 +27,8 @@ public fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boole
 /**
  * Returns `true` if a substring of this string starting at the specified offset [startIndex] starts with the specified prefix.
  */
-public fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolean = false): Boolean {
+@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
+public actual fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolean = false): Boolean {
     if (!ignoreCase)
         return nativeStartsWith(prefix, startIndex)
     else
@@ -36,7 +38,8 @@ public fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolea
 /**
  * Returns `true` if this string ends with the specified suffix.
  */
-public fun String.endsWith(suffix: String, ignoreCase: Boolean = false): Boolean {
+@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
+public actual fun String.endsWith(suffix: String, ignoreCase: Boolean = false): Boolean {
     if (!ignoreCase)
         return nativeEndsWith(suffix)
     else
diff --git a/libraries/stdlib/jvm/src/kotlin/text/StringsJVM.kt b/libraries/stdlib/jvm/src/kotlin/text/StringsJVM.kt
index d6166d4a637..b2bd93fece7 100644
--- a/libraries/stdlib/jvm/src/kotlin/text/StringsJVM.kt
+++ b/libraries/stdlib/jvm/src/kotlin/text/StringsJVM.kt
@@ -191,7 +191,8 @@ public actual inline fun String.substring(startIndex: Int, endIndex: Int): Strin
 /**
  * Returns `true` if this string starts with the specified prefix.
  */
-public fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boolean {
+@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
+public actual fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boolean {
     if (!ignoreCase)
         return (this as java.lang.String).startsWith(prefix)
     else
@@ -201,7 +202,8 @@ public fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boole
 /**
  * Returns `true` if a substring of this string starting at the specified offset [startIndex] starts with the specified prefix.
  */
-public fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolean = false): Boolean {
+@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
+public actual fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolean = false): Boolean {
     if (!ignoreCase)
         return (this as java.lang.String).startsWith(prefix, startIndex)
     else
@@ -211,7 +213,8 @@ public fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolea
 /**
  * Returns `true` if this string ends with the specified suffix.
  */
-public fun String.endsWith(suffix: String, ignoreCase: Boolean = false): Boolean {
+@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
+public actual fun String.endsWith(suffix: String, ignoreCase: Boolean = false): Boolean {
     if (!ignoreCase)
         return (this as java.lang.String).endsWith(suffix)
     else