diff --git a/mazerunner/src/main/java/com/bugsnag/android/TestHarnessHooks.kt b/mazerunner/src/main/java/com/bugsnag/android/TestHarnessHooks.kt
index 9a3d2ce91c..98bea56795 100644
--- a/mazerunner/src/main/java/com/bugsnag/android/TestHarnessHooks.kt
+++ b/mazerunner/src/main/java/com/bugsnag/android/TestHarnessHooks.kt
@@ -67,6 +67,6 @@ internal fun createCustomHeaderDelivery(context: Context): Delivery {
 
 internal fun writeErrorToStore(client: Client) {
     val error = Error.Builder(Configuration("api-key"), RuntimeException(), null,
-        Thread.currentThread()).build()
+        Thread.currentThread(), false).build()
     client.errorStore.write(error)
 }
diff --git a/sdk/src/androidTest/java/com/bugsnag/android/BeforeNotifyTest.kt b/sdk/src/androidTest/java/com/bugsnag/android/BeforeNotifyTest.kt
index 1132f9ce5b..279cc061ff 100644
--- a/sdk/src/androidTest/java/com/bugsnag/android/BeforeNotifyTest.kt
+++ b/sdk/src/androidTest/java/com/bugsnag/android/BeforeNotifyTest.kt
@@ -24,7 +24,7 @@ class BeforeNotifyTest {
         }
 
         val error = Error.Builder(config, RuntimeException("Test"), null,
-            Thread.currentThread()).build()
+            Thread.currentThread(), false).build()
         beforeNotify.run(error)
         assertEquals(context, error.context)
     }
diff --git a/sdk/src/androidTest/java/com/bugsnag/android/ErrorStoreTest.java b/sdk/src/androidTest/java/com/bugsnag/android/ErrorStoreTest.java
index eddf017cfb..6b84c75f01 100644
--- a/sdk/src/androidTest/java/com/bugsnag/android/ErrorStoreTest.java
+++ b/sdk/src/androidTest/java/com/bugsnag/android/ErrorStoreTest.java
@@ -72,7 +72,7 @@ public void testWrite() throws Exception {
     @NonNull
     private Error writeErrorToStore() {
         Error error = new Error.Builder(config, new RuntimeException(),
-            null, Thread.currentThread()).build();
+            null, Thread.currentThread(), false).build();
         errorStore.write(error);
         return error;
     }
diff --git a/sdk/src/androidTest/java/com/bugsnag/android/ErrorTest.java b/sdk/src/androidTest/java/com/bugsnag/android/ErrorTest.java
index 082eb846a2..f35bfa1bef 100644
--- a/sdk/src/androidTest/java/com/bugsnag/android/ErrorTest.java
+++ b/sdk/src/androidTest/java/com/bugsnag/android/ErrorTest.java
@@ -41,7 +41,7 @@ public class ErrorTest {
     public void setUp() throws Exception {
         config = new Configuration("api-key");
         RuntimeException exception = new RuntimeException("Example message");
-        error = new Error.Builder(config, exception, null, Thread.currentThread()).build();
+        error = new Error.Builder(config, exception, null, Thread.currentThread(), false).build();
     }
 
     @After
@@ -56,13 +56,13 @@ public void testShouldIgnoreClass() {
         // Shouldn't ignore classes not in ignoreClasses
         RuntimeException runtimeException = new RuntimeException("Test");
         Error error = new Error.Builder(config,
-            runtimeException, null, Thread.currentThread()).build();
+            runtimeException, null, Thread.currentThread(), false).build();
         assertFalse(error.shouldIgnoreClass());
 
         // Should ignore errors in ignoreClasses
         IOException ioException = new IOException("Test");
         error = new Error.Builder(config,
-            ioException, null, Thread.currentThread()).build();
+            ioException, null, Thread.currentThread(), false).build();
         assertTrue(error.shouldIgnoreClass());
     }
 
@@ -94,7 +94,7 @@ public void testBasicSerialization() throws JSONException, IOException {
     @Test
     public void testHandledSerialisation() throws Exception {
         Error err = new Error.Builder(config,
-            new RuntimeException(), null, Thread.currentThread())
+            new RuntimeException(), null, Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_HANDLED_EXCEPTION)
             .build();
 
@@ -112,7 +112,7 @@ public void testHandledSerialisation() throws Exception {
     @Test
     public void testUnhandledSerialisation() throws Exception {
         Error err = new Error.Builder(config,
-            new RuntimeException(), null, Thread.currentThread())
+            new RuntimeException(), null, Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_UNHANDLED_EXCEPTION)
             .severity(Severity.ERROR)
             .build();
@@ -131,7 +131,7 @@ public void testUnhandledSerialisation() throws Exception {
     @Test
     public void testPromiseRejectionSerialisation() throws Exception {
         Error err = new Error.Builder(config,
-            new RuntimeException(), null, Thread.currentThread())
+            new RuntimeException(), null, Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_PROMISE_REJECTION)
             .severity(Severity.ERROR)
             .build();
@@ -150,7 +150,7 @@ public void testPromiseRejectionSerialisation() throws Exception {
     @Test
     public void testLogSerialisation() throws Exception {
         Error err = new Error.Builder(config,
-            new RuntimeException(), null, Thread.currentThread())
+            new RuntimeException(), null, Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_LOG)
             .severity(Severity.WARNING)
             .attributeValue("warning")
@@ -186,7 +186,7 @@ public void testUserSpecifiedSerialisation() throws Exception {
     @Test
     public void testStrictModeSerialisation() throws Exception {
         Error err = new Error.Builder(config,
-            new RuntimeException(), null, Thread.currentThread())
+            new RuntimeException(), null, Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_STRICT_MODE)
             .attributeValue("Test")
             .build();
@@ -252,7 +252,7 @@ public void testSetSeverity() throws JSONException, IOException {
     public void testSessionIncluded() throws Exception {
         Session session = generateSession();
         Error err = new Error.Builder(config,
-            new RuntimeException(), session, Thread.currentThread()).build();
+            new RuntimeException(), session, Thread.currentThread(), false).build();
 
         JSONObject errorJson = streamableToJson(err);
         assertNotNull(errorJson);
@@ -273,7 +273,7 @@ public void testSessionIncluded() throws Exception {
     @Test(expected = JSONException.class)
     public void testSessionExcluded() throws Exception {
         Error err = new Error.Builder(config,
-            new RuntimeException(), null, Thread.currentThread()).build();
+            new RuntimeException(), null, Thread.currentThread(), false).build();
 
         JSONObject errorJson = streamableToJson(err);
         assertNotNull(errorJson);
@@ -284,11 +284,11 @@ public void testSessionExcluded() throws Exception {
     public void checkExceptionMessageNullity() throws Exception {
         String msg = "Foo";
         Error err = new Error.Builder(config,
-            new RuntimeException(msg), null, Thread.currentThread()).build();
+            new RuntimeException(msg), null, Thread.currentThread(), false).build();
         assertEquals(msg, err.getExceptionMessage());
 
         err = new Error.Builder(config,
-            new RuntimeException(), null, Thread.currentThread()).build();
+            new RuntimeException(), null, Thread.currentThread(), false).build();
         assertEquals("", err.getExceptionMessage());
     }
 
@@ -310,7 +310,7 @@ public void testBugsnagExceptionName() throws Exception {
         BugsnagException exception = new BugsnagException("Busgang", "exceptional",
             new StackTraceElement[]{});
         Error err = new Error.Builder(config,
-            exception, null, Thread.currentThread()).build();
+            exception, null, Thread.currentThread(), false).build();
         assertEquals("Busgang", err.getExceptionName());
     }
 
@@ -370,7 +370,7 @@ public void testSetUser() throws Exception {
     public void testBuilderMetaData() {
         Configuration config = new Configuration("api-key");
         Error.Builder builder = new Error.Builder(config,
-            new RuntimeException("foo"), null, Thread.currentThread());
+            new RuntimeException("foo"), null, Thread.currentThread(), false);
 
         assertNotNull(builder.metaData(new MetaData()).build());
 
@@ -414,7 +414,8 @@ public void testBuilderNullSession() throws Throwable {
 
         Session session = generateSession();
         session.setAutoCaptured(true);
-        error = new Error.Builder(config, exception, session, Thread.currentThread()).build();
+        error = new Error.Builder(config, exception, session,
+            Thread.currentThread(), false).build();
 
         JSONObject errorJson = streamableToJson(error);
         assertFalse(errorJson.has("session"));
diff --git a/sdk/src/androidTest/java/com/bugsnag/android/NullMetadataTest.java b/sdk/src/androidTest/java/com/bugsnag/android/NullMetadataTest.java
index 0e03cdba01..7ec7736467 100644
--- a/sdk/src/androidTest/java/com/bugsnag/android/NullMetadataTest.java
+++ b/sdk/src/androidTest/java/com/bugsnag/android/NullMetadataTest.java
@@ -42,7 +42,8 @@ public void tearDown() throws Exception {
 
     @Test
     public void testErrorDefaultMetaData() throws Exception {
-        Error error = new Error.Builder(config, throwable, null, Thread.currentThread()).build();
+        Error error = new Error.Builder(config, throwable, null,
+            Thread.currentThread(), false).build();
         validateDefaultMetadata(error.getMetaData());
     }
 
@@ -56,7 +57,8 @@ public void testSecondErrorDefaultMetaData() throws Exception {
 
     @Test
     public void testErrorSetMetadataRef() throws Exception {
-        Error error = new Error.Builder(config, throwable, null, Thread.currentThread()).build();
+        Error error = new Error.Builder(config, throwable, null,
+            Thread.currentThread(), false).build();
         MetaData metaData = new MetaData();
         metaData.addToTab(TAB_KEY, "test", "data");
         error.setMetaData(metaData);
@@ -65,7 +67,8 @@ public void testErrorSetMetadataRef() throws Exception {
 
     @Test
     public void testErrorSetNullMetadata() throws Exception {
-        Error error = new Error.Builder(config, throwable, null, Thread.currentThread()).build();
+        Error error = new Error.Builder(config, throwable, null,
+            Thread.currentThread(), false).build();
         error.setMetaData(null);
         validateDefaultMetadata(error.getMetaData());
     }
@@ -99,7 +102,7 @@ public boolean run(Error error) {
             }
         });
         Error error = new Error.Builder(config, new Throwable(),
-            null, Thread.currentThread()).build();
+            null, Thread.currentThread(), false).build();
         Client client = Bugsnag.getClient();
         client.notify(error, DeliveryStyle.SAME_THREAD, null);
     }
diff --git a/sdk/src/androidTest/java/com/bugsnag/android/ReportTest.java b/sdk/src/androidTest/java/com/bugsnag/android/ReportTest.java
index 5a32c3b063..10e4a76e52 100644
--- a/sdk/src/androidTest/java/com/bugsnag/android/ReportTest.java
+++ b/sdk/src/androidTest/java/com/bugsnag/android/ReportTest.java
@@ -31,7 +31,8 @@ public class ReportTest {
     public void setUp() throws Exception {
         Configuration config = new Configuration("example-api-key");
         RuntimeException exception = new RuntimeException("Something broke");
-        Error error = new Error.Builder(config, exception, null, Thread.currentThread()).build();
+        Error error = new Error.Builder(config, exception, null,
+            Thread.currentThread(), false).build();
         report = new Report("api-key", error);
     }
 
diff --git a/sdk/src/main/java/com/bugsnag/android/Client.java b/sdk/src/main/java/com/bugsnag/android/Client.java
index 64e1d8896e..7a8dd329c9 100644
--- a/sdk/src/main/java/com/bugsnag/android/Client.java
+++ b/sdk/src/main/java/com/bugsnag/android/Client.java
@@ -762,7 +762,7 @@ public void beforeRecordBreadcrumb(BeforeRecordBreadcrumb beforeRecordBreadcrumb
      */
     public void notify(@NonNull Throwable exception) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_HANDLED_EXCEPTION)
             .build();
         notify(error, !BLOCKING);
@@ -777,7 +777,7 @@ public void notify(@NonNull Throwable exception) {
      */
     public void notify(@NonNull Throwable exception, Callback callback) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_HANDLED_EXCEPTION)
             .build();
         notify(error, DeliveryStyle.ASYNC, callback);
@@ -812,7 +812,7 @@ public void notify(@NonNull String name,
      */
     public void notify(@NonNull Throwable exception, Severity severity) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .severity(severity)
             .build();
         notify(error, !BLOCKING);
@@ -829,7 +829,7 @@ public void notify(@NonNull Throwable exception, Severity severity) {
     public void notify(@NonNull Throwable exception,
                        @NonNull MetaData metaData) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .metaData(metaData)
             .severityReasonType(HandledState.REASON_HANDLED_EXCEPTION)
             .build();
@@ -849,7 +849,7 @@ public void notify(@NonNull Throwable exception,
     public void notify(@NonNull Throwable exception, Severity severity,
                        @NonNull MetaData metaData) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .metaData(metaData)
             .severity(severity)
             .build();
@@ -1011,7 +1011,7 @@ public void run() {
      */
     public void notifyBlocking(@NonNull Throwable exception) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_HANDLED_EXCEPTION)
             .build();
         notify(error, BLOCKING);
@@ -1026,7 +1026,7 @@ public void notifyBlocking(@NonNull Throwable exception) {
      */
     public void notifyBlocking(@NonNull Throwable exception, Callback callback) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_HANDLED_EXCEPTION)
             .build();
         notify(error, DeliveryStyle.SAME_THREAD, callback);
@@ -1063,7 +1063,7 @@ public void notifyBlocking(@NonNull String name,
     public void notifyBlocking(@NonNull Throwable exception,
                                @NonNull MetaData metaData) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .severityReasonType(HandledState.REASON_HANDLED_EXCEPTION)
             .metaData(metaData)
             .build();
@@ -1083,7 +1083,7 @@ public void notifyBlocking(@NonNull Throwable exception,
     public void notifyBlocking(@NonNull Throwable exception, Severity severity,
                                @NonNull MetaData metaData) {
         Error error = new Error.Builder(config, exception, sessionTracker.getCurrentSession(),
-            Thread.currentThread())
+            Thread.currentThread(), false)
             .metaData(metaData)
             .severity(severity)
             .build();
@@ -1154,7 +1154,7 @@ public void notifyBlocking(@NonNull String name,
      */
     public void notifyBlocking(@NonNull Throwable exception, Severity severity) {
         Error error = new Error.Builder(config, exception,
-            sessionTracker.getCurrentSession(), Thread.currentThread())
+            sessionTracker.getCurrentSession(), Thread.currentThread(), false)
             .severity(severity)
             .build();
         notify(error, BLOCKING);
@@ -1183,7 +1183,7 @@ public void internalClientNotify(@NonNull Throwable exception,
 
         @SuppressWarnings("WrongConstant")
         Error error = new Error.Builder(config, exception,
-            sessionTracker.getCurrentSession(), Thread.currentThread())
+            sessionTracker.getCurrentSession(), Thread.currentThread(), false)
             .severity(Severity.fromString(severity))
             .severityReasonType(severityReason)
             .attributeValue(logLevel)
@@ -1342,7 +1342,7 @@ void cacheAndNotify(@NonNull Throwable exception, Severity severity, MetaData me
                         @HandledState.SeverityReason String severityReason,
                         @Nullable String attributeValue, Thread thread) {
         Error error = new Error.Builder(config, exception,
-            sessionTracker.getCurrentSession(), thread)
+            sessionTracker.getCurrentSession(), thread, true)
             .severity(severity)
             .metaData(metaData)
             .severityReasonType(severityReason)
diff --git a/sdk/src/main/java/com/bugsnag/android/Error.java b/sdk/src/main/java/com/bugsnag/android/Error.java
index 15c90ae0b1..e968559495 100644
--- a/sdk/src/main/java/com/bugsnag/android/Error.java
+++ b/sdk/src/main/java/com/bugsnag/android/Error.java
@@ -401,9 +401,11 @@ static class Builder {
 
         Builder(@NonNull Configuration config,
                 @NonNull Throwable exception,
-                Session session,
-                Thread thread) {
-            this.threadState = new ThreadState(config, thread, Thread.getAllStackTraces(), null);
+                @Nullable Session session,
+                @NonNull Thread thread,
+                boolean unhandled) {
+            Throwable exc = unhandled ? exception : null;
+            this.threadState = new ThreadState(config, thread, Thread.getAllStackTraces(), exc);
             this.config = config;
             this.exception = exception;
             this.severityReasonType = HandledState.REASON_USER_SPECIFIED; // default
@@ -419,7 +421,7 @@ static class Builder {
         Builder(@NonNull Configuration config, @NonNull String name,
                 @NonNull String message, @NonNull StackTraceElement[] frames,
                 Session session, Thread thread) {
-            this(config, new BugsnagException(name, message, frames), session, thread);
+            this(config, new BugsnagException(name, message, frames), session, thread, false);
         }
 
         Builder severityReasonType(@HandledState.SeverityReason String severityReasonType) {