diff --git a/src/Mail/ResentMessage.php b/src/Mail/ResentMessage.php
index 1dfcd43..3da659c 100644
--- a/src/Mail/ResentMessage.php
+++ b/src/Mail/ResentMessage.php
@@ -66,11 +66,13 @@ public function build(): static
 
         $this->withSymfonyMessage($this->propagateContext());
 
-        foreach ((array) $this->record->tags as $tag) {
+        // A resend of a resend already carries "resent"; one is enough, since
+        // resent_from_id records the depth.
+        foreach (array_unique([...(array) $this->record->tags, 'resent']) as $tag) {
             $this->tag($tag);
         }
 
-        return $this->tag('resent');
+        return $this;
     }
 
     /**
diff --git a/tests/ResendTest.php b/tests/ResendTest.php
index ba345da..3ea306a 100644
--- a/tests/ResendTest.php
+++ b/tests/ResendTest.php
@@ -146,4 +146,18 @@ public function testTrackingResentFromIsRespected()
         $latest = EmailMessage::latest('id')->first();
         $this->assertSame($original->id, $latest->resent_from_id);
     }
+
+    public function testResendingAResendKeepsASingleResentTag()
+    {
+        Mail::send(new class extends \Illuminate\Mail\Mailable {
+            public function build(): static
+            {
+                return $this->to('r@example.com')->subject('Hi')->html('<p>Hi</p>')->tag('receipt')->tag('receipt');
+            }
+        });
+        Postmaster::resend(EmailMessage::first());
+        Postmaster::resend(EmailMessage::latest('id')->first());
+
+        $this->assertSame(['receipt', 'resent'], EmailMessage::latest('id')->first()->tags);
+    }
 }