diff --git a/google-cloud-clients/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/stub/SubscriberStubSettings.java b/google-cloud-clients/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/stub/SubscriberStubSettings.java
index 9d683ee79520..c8f6ad9bc191 100644
--- a/google-cloud-clients/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/stub/SubscriberStubSettings.java
+++ b/google-cloud-clients/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/stub/SubscriberStubSettings.java
@@ -267,7 +267,8 @@ public static GoogleCredentialsProvider.Builder defaultCredentialsProviderBuilde
 
   /** Returns a builder for the default ChannelProvider for this service. */
   public static InstantiatingGrpcChannelProvider.Builder defaultGrpcTransportProviderBuilder() {
-    return InstantiatingGrpcChannelProvider.newBuilder();
+    return InstantiatingGrpcChannelProvider.newBuilder()
+            .setMaxInboundMessageSize(20<<20); // 20MB
   }
 
   public static TransportChannelProvider defaultTransportChannelProvider() {