diff --git a/server/src/main/java/org/elasticsearch/action/support/broadcast/BaseBroadcastResponse.java b/server/src/main/java/org/elasticsearch/action/support/broadcast/BaseBroadcastResponse.java
index c7e4de245d4d9..f6ad9bdac3c7e 100644
--- a/server/src/main/java/org/elasticsearch/action/support/broadcast/BaseBroadcastResponse.java
+++ b/server/src/main/java/org/elasticsearch/action/support/broadcast/BaseBroadcastResponse.java
@@ -84,6 +84,13 @@ public int getFailedShards() {
         return failedShards;
     }
 
+    /**
+     * The shards that were not available when the request was executed.
+     */
+    public int getUnavailableShards() {
+        return totalShards - successfulShards - failedShards;
+    }
+
     /**
      * The REST status that should be used for the response
      */
diff --git a/server/src/test/java/org/elasticsearch/action/support/replication/BroadcastReplicationTests.java b/server/src/test/java/org/elasticsearch/action/support/replication/BroadcastReplicationTests.java
index 98c83ba796220..45d0ce838e897 100644
--- a/server/src/test/java/org/elasticsearch/action/support/replication/BroadcastReplicationTests.java
+++ b/server/src/test/java/org/elasticsearch/action/support/replication/BroadcastReplicationTests.java
@@ -167,7 +167,7 @@ public void testNotStartedPrimary() throws InterruptedException, ExecutionExcept
         response.get();
         logger.info("total shards: {}, ", response.get().getTotalShards());
         // we expect no failures here because UnavailableShardsException does not count as failed
-        assertBroadcastResponse(2, 0, 0, response.get(), null);
+        assertBroadcastResponse(2, 0, 0, 2, response.get(), null);
     }
 
     public void testStartedPrimary() throws InterruptedException, ExecutionException {
@@ -194,23 +194,28 @@ public void testResultCombine() throws InterruptedException, ExecutionException,
         ActionTestUtils.execute(broadcastReplicationAction, null, new DummyBroadcastRequest().indices(index), response);
         int succeeded = 0;
         int failed = 0;
+        int unavailable = 0;
         for (Tuple<ShardId, ActionListener<ReplicationResponse>> shardRequests : broadcastReplicationAction.capturedShardRequests) {
             if (randomBoolean()) {
                 ReplicationResponse.ShardInfo.Failure[] failures = new ReplicationResponse.ShardInfo.Failure[0];
                 int shardsSucceeded = randomInt(1) + 1;
                 succeeded += shardsSucceeded;
                 ReplicationResponse replicationResponse = new ReplicationResponse();
-                if (shardsSucceeded == 1 && randomBoolean()) {
-                    // sometimes add failure (no failure means shard unavailable)
-                    failures = new ReplicationResponse.ShardInfo.Failure[1];
-                    failures[0] = new ReplicationResponse.ShardInfo.Failure(
-                        shardRequests.v1(),
-                        null,
-                        new Exception("pretend shard failed"),
-                        RestStatus.GATEWAY_TIMEOUT,
-                        false
-                    );
-                    failed++;
+                if (shardsSucceeded == 1) {
+                    if (randomBoolean()) {
+                        // sometimes add failure (no failure means shard unavailable)
+                        failures = new ReplicationResponse.ShardInfo.Failure[1];
+                        failures[0] = new ReplicationResponse.ShardInfo.Failure(
+                            shardRequests.v1(),
+                            null,
+                            new Exception("pretend shard failed"),
+                            RestStatus.GATEWAY_TIMEOUT,
+                            false
+                        );
+                        failed++;
+                    } else {
+                        unavailable++;
+                    }
                 }
                 replicationResponse.setShardInfo(ReplicationResponse.ShardInfo.of(2, shardsSucceeded, failures));
                 shardRequests.v2().onResponse(replicationResponse);
@@ -221,7 +226,7 @@ public void testResultCombine() throws InterruptedException, ExecutionException,
                 shardRequests.v2().onFailure(new Exception("pretend shard failed"));
             }
         }
-        assertBroadcastResponse(2 * numShards, succeeded, failed, response.get(), Exception.class);
+        assertBroadcastResponse(2 * numShards, succeeded, failed, unavailable, response.get(), Exception.class);
     }
 
     public void testNoShards() throws InterruptedException, ExecutionException, IOException {
@@ -338,15 +343,27 @@ public BaseBroadcastResponse executeAndAssertImmediateResponse(
         return response.actionGet(5, TimeUnit.SECONDS);
     }
 
-    private void assertBroadcastResponse(int total, int successful, int failed, BaseBroadcastResponse response, Class<?> exceptionClass) {
+    private void assertBroadcastResponse(
+        int total,
+        int successful,
+        int failed,
+        int unavailable,
+        BaseBroadcastResponse response,
+        Class<?> exceptionClass
+    ) {
         assertThat(response.getSuccessfulShards(), equalTo(successful));
         assertThat(response.getTotalShards(), equalTo(total));
         assertThat(response.getFailedShards(), equalTo(failed));
+        assertThat(response.getUnavailableShards(), equalTo(unavailable));
         for (int i = 0; i < failed; i++) {
             assertThat(response.getShardFailures()[0].getCause().getCause(), instanceOf(exceptionClass));
         }
     }
 
+    private void assertBroadcastResponse(int total, int successful, int failed, BaseBroadcastResponse response, Class<?> exceptionClass) {
+        assertBroadcastResponse(total, successful, failed, 0, response, exceptionClass);
+    }
+
     /**
      * Copy index and routing table from default project to the target project.
      */