diff --git a/core/src/main/java/org/elasticsearch/ingest/IngestDocument.java b/core/src/main/java/org/elasticsearch/ingest/IngestDocument.java
index edb92b6e837..eaae1a3e881 100644
--- a/core/src/main/java/org/elasticsearch/ingest/IngestDocument.java
+++ b/core/src/main/java/org/elasticsearch/ingest/IngestDocument.java
@@ -27,18 +27,14 @@ import org.elasticsearch.index.mapper.RoutingFieldMapper;
 import org.elasticsearch.index.mapper.SourceFieldMapper;
 import org.elasticsearch.index.mapper.TypeFieldMapper;
 
-import java.text.DateFormat;
-import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Base64;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
-import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
-import java.util.TimeZone;
 
 /**
  * Represents a single document being captured before indexing and holds the source and metadata (like id, type and index).
@@ -68,9 +64,7 @@ public final class IngestDocument {
         }
 
         this.ingestMetadata = new HashMap<>();
-        DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZZ", Locale.ROOT);
-        df.setTimeZone(TimeZone.getTimeZone("UTC"));
-        this.ingestMetadata.put(TIMESTAMP, df.format(new Date()));
+        this.ingestMetadata.put(TIMESTAMP, new Date());
     }
 
     /**
@@ -595,6 +589,8 @@ public final class IngestDocument {
             value instanceof Long || value instanceof Float ||
             value instanceof Double || value instanceof Boolean) {
             return value;
+        } else if (value instanceof Date) {
+            return ((Date) value).clone();
         } else {
             throw new IllegalArgumentException("unexpected value type [" + value.getClass() + "]");
         }
diff --git a/core/src/test/java/org/elasticsearch/ingest/IngestDocumentTests.java b/core/src/test/java/org/elasticsearch/ingest/IngestDocumentTests.java
index e16be95d2e6..1bd5676f474 100644
--- a/core/src/test/java/org/elasticsearch/ingest/IngestDocumentTests.java
+++ b/core/src/test/java/org/elasticsearch/ingest/IngestDocumentTests.java
@@ -22,21 +22,17 @@ package org.elasticsearch.ingest;
 import org.elasticsearch.test.ESTestCase;
 import org.junit.Before;
 
-import java.text.DateFormat;
-import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
-import java.util.Locale;
 import java.util.Map;
 
 import static org.elasticsearch.ingest.IngestDocumentMatcher.assertIngestDocument;
 import static org.hamcrest.Matchers.both;
 import static org.hamcrest.Matchers.containsString;
-import static org.hamcrest.Matchers.endsWith;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.greaterThanOrEqualTo;
 import static org.hamcrest.Matchers.instanceOf;
@@ -48,13 +44,14 @@ import static org.hamcrest.Matchers.sameInstance;
 
 public class IngestDocumentTests extends ESTestCase {
 
+    private static final Date BOGUS_TIMESTAMP = new Date(0L);
     private IngestDocument ingestDocument;
 
     @Before
     public void setIngestDocument() {
         Map<String, Object> document = new HashMap<>();
         Map<String, Object> ingestMap = new HashMap<>();
-        ingestMap.put("timestamp", "bogus_timestamp");
+        ingestMap.put("timestamp", BOGUS_TIMESTAMP);
         document.put("_ingest", ingestMap);
         document.put("foo", "bar");
         document.put("int", 123);
@@ -86,9 +83,9 @@ public class IngestDocumentTests extends ESTestCase {
         assertThat(ingestDocument.getFieldValue("_index", String.class), equalTo("index"));
         assertThat(ingestDocument.getFieldValue("_type", String.class), equalTo("type"));
         assertThat(ingestDocument.getFieldValue("_id", String.class), equalTo("id"));
-        assertThat(ingestDocument.getFieldValue("_ingest.timestamp", String.class),
-                both(notNullValue()).and(not(equalTo("bogus_timestamp"))));
-        assertThat(ingestDocument.getFieldValue("_source._ingest.timestamp", String.class), equalTo("bogus_timestamp"));
+        assertThat(ingestDocument.getFieldValue("_ingest.timestamp", Date.class),
+                both(notNullValue()).and(not(equalTo(BOGUS_TIMESTAMP))));
+        assertThat(ingestDocument.getFieldValue("_source._ingest.timestamp", Date.class), equalTo(BOGUS_TIMESTAMP));
     }
 
     public void testGetSourceObject() {
@@ -972,11 +969,8 @@ public class IngestDocumentTests extends ESTestCase {
         long before = System.currentTimeMillis();
         IngestDocument ingestDocument = RandomDocumentPicks.randomIngestDocument(random());
         long after = System.currentTimeMillis();
-        String timestampString = (String) ingestDocument.getIngestMetadata().get("timestamp");
-        assertThat(timestampString, notNullValue());
-        assertThat(timestampString, endsWith("+0000"));
-        DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZZ", Locale.ROOT);
-        Date timestamp = df.parse(timestampString);
+        Date timestamp = (Date) ingestDocument.getIngestMetadata().get(IngestDocument.TIMESTAMP);
+        assertThat(timestamp, notNullValue());
         assertThat(timestamp.getTime(), greaterThanOrEqualTo(before));
         assertThat(timestamp.getTime(), lessThanOrEqualTo(after));
     }
diff --git a/docs/reference/migration/migrate_6_0.asciidoc b/docs/reference/migration/migrate_6_0.asciidoc
index f1712d29cf9..abc476a7d1b 100644
--- a/docs/reference/migration/migrate_6_0.asciidoc
+++ b/docs/reference/migration/migrate_6_0.asciidoc
@@ -35,6 +35,7 @@ way to reindex old indices is to use the `reindex` API.
 * <<breaking_60_plugins_changes>>
 * <<breaking_60_indices_changes>>
 * <<breaking_60_scripting_changes>>
+* <<breaking_60_ingest_changes>>
 
 include::migrate_6_0/cat.asciidoc[]
 
@@ -57,3 +58,5 @@ include::migrate_6_0/plugins.asciidoc[]
 include::migrate_6_0/indices.asciidoc[]
 
 include::migrate_6_0/scripting.asciidoc[]
+
+include::migrate_6_0/ingest.asciidoc[]
diff --git a/docs/reference/migration/migrate_6_0/ingest.asciidoc b/docs/reference/migration/migrate_6_0/ingest.asciidoc
new file mode 100644
index 00000000000..db2caabe43a
--- /dev/null
+++ b/docs/reference/migration/migrate_6_0/ingest.asciidoc
@@ -0,0 +1,6 @@
+[[breaking_60_ingest_changes]]
+=== Ingest changes
+
+==== Timestamp meta-data field type has changed
+
+The type of the "timestamp" meta-data field has changed from `java.lang.String` to `java.util.Date`.
\ No newline at end of file