diff --git a/app/core/core-common-public/src/androidMain/kotlin/com/hedvig/core/common/android/validation/ValidateEmail.kt b/app/core/core-common-public/src/androidMain/kotlin/com/hedvig/core/common/android/validation/ValidateEmail.kt
index bc9e79c9af..eb64a2733b 100644
--- a/app/core/core-common-public/src/androidMain/kotlin/com/hedvig/core/common/android/validation/ValidateEmail.kt
+++ b/app/core/core-common-public/src/androidMain/kotlin/com/hedvig/core/common/android/validation/ValidateEmail.kt
@@ -11,6 +11,6 @@ fun validateEmail(email: CharSequence): ValidationResult {
   }
 }
 
-fun isValidEmail(email: String): Boolean {
+actual fun isValidEmail(email: String): Boolean {
   return email.isNotBlank() && PatternsCompat.EMAIL_ADDRESS.matcher(email).matches()
 }
diff --git a/app/core/core-common-public/src/commonMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.kt b/app/core/core-common-public/src/commonMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.kt
new file mode 100644
index 0000000000..0977718768
--- /dev/null
+++ b/app/core/core-common-public/src/commonMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.kt
@@ -0,0 +1,16 @@
+package com.hedvig.core.common.android.validation
+
+expect fun isValidEmail(email: String): Boolean
+
+/**
+ * The pattern of `androidx.core.util.PatternsCompat.EMAIL_ADDRESS`, so targets without androidx.core
+ * accept exactly the same addresses as Android.
+ */
+internal const val EMAIL_ADDRESS_PATTERN: String =
+  "[a-zA-Z0-9\\+\\.\\_\\%\\-\\+]{1,256}" +
+    "\\@" +
+    "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}" +
+    "(" +
+    "\\." +
+    "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,25}" +
+    ")+"
diff --git a/app/core/core-common-public/src/commonTest/kotlin/com/hedvig/core/common/android/validation/IsValidEmailTest.kt b/app/core/core-common-public/src/commonTest/kotlin/com/hedvig/core/common/android/validation/IsValidEmailTest.kt
new file mode 100644
index 0000000000..f5525878fd
--- /dev/null
+++ b/app/core/core-common-public/src/commonTest/kotlin/com/hedvig/core/common/android/validation/IsValidEmailTest.kt
@@ -0,0 +1,37 @@
+package com.hedvig.core.common.android.validation
+
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class IsValidEmailTest {
+  @Test
+  fun acceptsValidEmails() {
+    listOf(
+      "a@b.co",
+      "first.last@example.com",
+      "user+tag@sub.example.org",
+      "USER_1%x-y@example-domain.se",
+    ).forEach { email ->
+      assertTrue(isValidEmail(email), "Expected \"$email\" to be valid")
+    }
+  }
+
+  @Test
+  fun rejectsInvalidEmails() {
+    listOf(
+      "",
+      "   ",
+      "plainaddress",
+      "@example.com",
+      "user@",
+      "user@example",
+      "user name@example.com",
+      " user@example.com",
+      "user@example.com ",
+      "user@@example.com",
+    ).forEach { email ->
+      assertFalse(isValidEmail(email), "Expected \"$email\" to be invalid")
+    }
+  }
+}
diff --git a/app/core/core-common-public/src/jvmMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.jvm.kt b/app/core/core-common-public/src/jvmMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.jvm.kt
new file mode 100644
index 0000000000..9fd22569f6
--- /dev/null
+++ b/app/core/core-common-public/src/jvmMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.jvm.kt
@@ -0,0 +1,7 @@
+package com.hedvig.core.common.android.validation
+
+private val emailAddressRegex = Regex(EMAIL_ADDRESS_PATTERN)
+
+actual fun isValidEmail(email: String): Boolean {
+  return email.isNotBlank() && emailAddressRegex.matches(email)
+}
diff --git a/app/core/core-common-public/src/nativeMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.native.kt b/app/core/core-common-public/src/nativeMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.native.kt
new file mode 100644
index 0000000000..9fd22569f6
--- /dev/null
+++ b/app/core/core-common-public/src/nativeMain/kotlin/com/hedvig/core/common/android/validation/IsValidEmail.native.kt
@@ -0,0 +1,7 @@
+package com.hedvig.core.common.android.validation
+
+private val emailAddressRegex = Regex(EMAIL_ADDRESS_PATTERN)
+
+actual fun isValidEmail(email: String): Boolean {
+  return email.isNotBlank() && emailAddressRegex.matches(email)
+}