diff --git a/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt b/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt
index 3372450..2b26845 100644
--- a/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt
+++ b/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt
@@ -23,6 +23,7 @@ abstract class AbstractTest {
     protected val testUuid = UUID.fromString("aaaaaaaa-bbbb-4ccc-8ddd-0123456789ab")
     protected val toNumber = "447712345689"
     protected val altNumber = "447700900001"
+    protected val text = "Hello, World!"
     protected val networkCode = "65512"
     protected val startTime = "2020-09-17T12:34:56Z"
     protected val endTime = "2021-09-17T12:35:28Z"
diff --git a/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt b/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt
index 47f9731..343a6b1 100644
--- a/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt
+++ b/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt
@@ -21,7 +21,6 @@ class MessagesTest : AbstractTest() {
     private val whatsappChannel = "whatsapp"
     private val viberChannel = "viber_service"
     private val messengerChannel = "messenger"
-    private val text = "Hello, World!"
     private val caption = "Additional text to accompany the media"
     private val imageUrl = "https://example.com/image.jpg"
     private val audioUrl = "https://example.com/audio.mp3"
diff --git a/src/test/kotlin/com/vonage/client/kt/VoiceTest.kt b/src/test/kotlin/com/vonage/client/kt/VoiceTest.kt
index 9c45f07..ca6a490 100644
--- a/src/test/kotlin/com/vonage/client/kt/VoiceTest.kt
+++ b/src/test/kotlin/com/vonage/client/kt/VoiceTest.kt
@@ -3,6 +3,9 @@ package com.vonage.client.kt
 import com.vonage.client.voice.CallDirection
 import com.vonage.client.voice.CallStatus
 import com.vonage.client.voice.PhoneEndpoint
+import com.vonage.client.voice.ncco.Ncco
+import com.vonage.client.voice.ncco.TalkAction
+import java.net.URI
 import java.time.Instant
 import java.util.*
 import kotlin.test.Test
@@ -17,8 +20,18 @@ class VoiceTest : AbstractTest() {
     private val callObj = voiceClient.call(UUID.fromString(callIdStr))
     private val conversationId = "CON-f972836a-550f-45fa-956c-12a2ab5b7d22"
 
-    private fun testModifyCall(actionName: String, invocation: () -> Unit) {
-        mockPut(expectedUrl = callUrl, expectedRequestParams = mapOf("action" to actionName), status = 204)
+    private fun testModifyCall(actionName: String = "transfer", invocation: () -> Unit,
+                               nccoAction: Map<String, Any>? = null, nccoUrl: String? = null) {
+        mockPut(expectedUrl = callUrl,
+            expectedRequestParams = mapOf("action" to actionName) + (
+                        if (actionName == "transfer") mapOf(
+                            "destination" to mapOf("type" to "ncco") +
+                            if (nccoUrl != null) mapOf("url" to listOf(nccoUrl))
+                            else mapOf("ncco" to listOf(nccoAction))
+                        ) else mapOf()
+                    ),
+            status = 204
+        )
         invocation.invoke()
     }
 
@@ -101,4 +114,20 @@ class VoiceTest : AbstractTest() {
         assertEquals(Instant.parse(endTime), response.endTime.toInstant())
         assertEquals(networkCode, response.network)
     }
+
+    @Test
+    fun `transfer call with answer url`() {
+        val answerUrl = "https://example.com/ncco.json"
+        testModifyCall(nccoUrl = answerUrl, invocation = {
+            callObj.transfer(URI.create(answerUrl))
+            callObj.transfer(answerUrl)
+        })
+    }
+
+    @Test
+    fun `transfer call with ncco`() {
+        testModifyCall(nccoAction = mapOf("action" to "talk", "text" to text), invocation = {
+            callObj.transfer(Ncco(TalkAction.builder(text).build()))
+        })
+    }
 }
\ No newline at end of file