diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/push/APNSender.java b/service/src/main/java/org/whispersystems/textsecuregcm/push/APNSender.java
index 9e1a4dd76..24761b77b 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/push/APNSender.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/push/APNSender.java
@@ -82,7 +82,8 @@ public class APNSender implements Managed {
     ListenableFuture<ApnResult> future = apnsClient.send(message.getApnId(), topic,
                                                          message.getMessage(),
                                                          Instant.ofEpochMilli(message.getExpirationTime()),
-                                                         message.isVoip());
+                                                         message.isVoip(),
+                                                         message.getCollapseId());
 
     Futures.addCallback(future, new FutureCallback<>() {
       @Override
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/push/ApnMessage.java b/service/src/main/java/org/whispersystems/textsecuregcm/push/ApnMessage.java
index 804200030..1c69b0921 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/push/ApnMessage.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/push/ApnMessage.java
@@ -66,6 +66,14 @@ public class ApnMessage {
     }
   }
 
+  @Nullable
+  public String getCollapseId() {
+    if (type == Type.NOTIFICATION && !isVoip) {
+      return "incoming-message";
+    }
+    return null;
+  }
+
   @VisibleForTesting
   public Optional<String> getChallengeData() {
     return challengeData;
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/push/RetryingApnsClient.java b/service/src/main/java/org/whispersystems/textsecuregcm/push/RetryingApnsClient.java
index 168dd46a3..119d9c1d2 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/push/RetryingApnsClient.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/push/RetryingApnsClient.java
@@ -67,9 +67,9 @@ public class RetryingApnsClient {
     this.apnsClient = apnsClient;
   }
 
-  ListenableFuture<ApnResult> send(final String apnId, final String topic, final String payload, final Instant expiration, final boolean isVoip) {
+  ListenableFuture<ApnResult> send(final String apnId, final String topic, final String payload, final Instant expiration, final boolean isVoip, final String collapseId) {
     SettableFuture<ApnResult>  result       = SettableFuture.create();
-    SimpleApnsPushNotification notification = new SimpleApnsPushNotification(apnId, topic, payload, expiration, DeliveryPriority.IMMEDIATE, isVoip ? PushType.VOIP : PushType.ALERT);
+    SimpleApnsPushNotification notification = new SimpleApnsPushNotification(apnId, topic, payload, expiration, DeliveryPriority.IMMEDIATE, isVoip ? PushType.VOIP : PushType.ALERT, collapseId);
         
     apnsClient.sendNotification(notification).whenComplete(new ResponseHandler(result));