diff --git a/src/applications/differential/mail/comment/DifferentialCommentMail.php b/src/applications/differential/mail/comment/DifferentialCommentMail.php
index 42eb8c7155..060264b166 100644
--- a/src/applications/differential/mail/comment/DifferentialCommentMail.php
+++ b/src/applications/differential/mail/comment/DifferentialCommentMail.php
@@ -45,9 +45,12 @@ class DifferentialCommentMail extends DifferentialMail {
   }
 
   protected function renderSubject() {
+    $verb = ucwords($this->getVerb());
     $revision = $this->getRevision();
-    $verb = $this->getVerb();
-    return ucwords($verb).': '.$revision->getTitle();
+    $title = $revision->getTitle();
+    $id = $revision->getID();
+    $subject = "[{$verb}] D{$id}: {$title}";
+    return $subject;
   }
 
   protected function getVerb() {
diff --git a/src/applications/maniphest/editor/transaction/ManiphestTransactionEditor.php b/src/applications/maniphest/editor/transaction/ManiphestTransactionEditor.php
index 8d4ac3430d..ade1eca2f6 100644
--- a/src/applications/maniphest/editor/transaction/ManiphestTransactionEditor.php
+++ b/src/applications/maniphest/editor/transaction/ManiphestTransactionEditor.php
@@ -17,6 +17,7 @@
  */
 
 class ManiphestTransactionEditor {
+  const SUBJECT_PREFIX = '[Maniphest]';
 
   public function applyTransactions($task, array $transactions) {
 
@@ -174,10 +175,11 @@ class ManiphestTransactionEditor {
       "  ".$task_uri."\n";
 
     $thread_id = '<maniphest-task-'.$task->getPHID().'>';
+    $task_id = $task->getID();
+    $title = $task->getTitle();
 
     id(new PhabricatorMetaMTAMail())
-      ->setSubject(
-        '[Maniphest] T'.$task->getID().' '.$action.': '.$task->getTitle())
+      ->setSubject(self::SUBJECT_PREFIX." [{$action}] T{$task_id}: {$title}")
       ->setFrom($transaction->getAuthorPHID())
       ->addTos($email_to)
       ->addCCs($email_cc)