diff --git a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplication.java b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplication.java
index 97bc6a07c..f2868b2d7 100644
--- a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplication.java
+++ b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplication.java
@@ -96,15 +96,12 @@ public class AggregateApplication {
 			Class<?>[] apps, String args[][]) {
 		for (int i = apps.length - 1; i >= 0; i--) {
 			String appClassName = apps[i].getName();
-			embedApp(parentContext, getNamespace(null, appClassName, i), apps[i])
+			embedApp(parentContext, getNamespace(appClassName, i), apps[i])
 					.run(args != null ? args[i] : new String[0]);
 		}
 	}
 
-	protected static String getNamespace(String namespace, String appClassName, int index) {
-		if (namespace != null) {
-			return namespace;
-		}
+	protected static String getNamespace(String appClassName, int index) {
 		return appClassName + "_" + index;
 	}
 
@@ -133,19 +130,15 @@ public class AggregateApplication {
 		int i = 0;
 		SubscribableChannel sharedChannel = null;
 		for (Entry<Class<?>, String> appEntry : appsWithNamespace.entrySet()) {
-			Class<?> app = appEntry.getKey();
 			String namespace = appEntry.getValue();
-			String appClassName = app.getName();
 			if (i > 0) {
-				sharedChannelRegistry.register(getNamespace(namespace, appClassName, i)
-						+ "." + INPUT_CHANNEL_NAME, sharedChannel);
+				sharedChannelRegistry.register(namespace + "." + INPUT_CHANNEL_NAME, sharedChannel);
 			}
 			sharedChannel = new DirectChannel();
 			if (i < appsWithNamespace.size() - 1) {
-				sharedChannelRegistry.register(getNamespace(namespace, appClassName, i)
-						+ "." + OUTPUT_CHANNEL_NAME, sharedChannel);
+				sharedChannelRegistry.register(namespace + "." + OUTPUT_CHANNEL_NAME, sharedChannel);
 			}
-			i ++;
+			i++;
 		}
 	}
 
diff --git a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplicationBuilder.java b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplicationBuilder.java
index bfb0f06f3..e01eafeff 100644
--- a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplicationBuilder.java
+++ b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/aggregate/AggregateApplicationBuilder.java
@@ -121,13 +121,15 @@ public class AggregateApplicationBuilder {
 		for (int i = 0; i < apps.size(); i++) {
 			AppConfigurer<?> appConfigurer = apps.get(i);
 			Class<?> appToEmbed = appConfigurer.getApp();
+			// Always update namespace before preparing SharedChannelRegistry
+			if (appConfigurer.namespace == null) {
+				appConfigurer.namespace = AggregateApplication.getNamespace(appConfigurer.getApp().getName(), i);
+			}
 			appsToEmbed.put(appToEmbed, appConfigurer.namespace);
 		}
 		AggregateApplication.prepareSharedChannelRegistry(sharedChannelRegistry, appsToEmbed);
 		for (int i = apps.size() - 1; i >= 0; i--) {
 			AppConfigurer<?> appConfigurer = apps.get(i);
-			appConfigurer.namespace(AggregateApplication
-					.getNamespace(appConfigurer.namespace, appConfigurer.getApp().getName(), i));
 			appConfigurer.embed();
 		}
 		return parentContext;