diff --git a/src/CP/Toasts/Toast.php b/src/CP/Toasts/Toast.php
index 57ad55a6a16..b53ad1f34f1 100644
--- a/src/CP/Toasts/Toast.php
+++ b/src/CP/Toasts/Toast.php
@@ -4,11 +4,12 @@
 
 use Exception;
 use Illuminate\Contracts\Support\Arrayable;
+use JsonSerializable;
 
 /**
  * Holds information about a toast message to show to the user.
  */
-class Toast implements Arrayable
+class Toast implements Arrayable, JsonSerializable
 {
     private const TYPES = ['error', 'success', 'info'];
     private $message;
@@ -43,6 +44,11 @@ public function toArray(): array
         ];
     }
 
+    public function jsonSerialize(): array
+    {
+        return $this->toArray();
+    }
+
     /**
      * @throws Exception
      */
diff --git a/tests/CP/Toasts/ManagerTest.php b/tests/CP/Toasts/ManagerTest.php
new file mode 100644
index 00000000000..4adb36713a4
--- /dev/null
+++ b/tests/CP/Toasts/ManagerTest.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace Tests\CP\Toasts;
+
+use Illuminate\Session\ArraySessionHandler;
+use Illuminate\Session\Store;
+use PHPUnit\Framework\Attributes\Test;
+use Statamic\CP\Toasts\Manager;
+use Tests\TestCase;
+
+class ManagerTest extends TestCase
+{
+    #[Test]
+    public function toasts_survive_json_session_serialization()
+    {
+        $handler = new ArraySessionHandler(120);
+        $sessionId = str_repeat('a', 40);
+
+        // Flash a toast, then persist the session using json serialization,
+        // like a request ending with a redirect would.
+        $session = new Store('test', $handler, $sessionId, 'json');
+        $session->start();
+        (new Manager($session))->success('Saved!');
+        $session->save();
+
+        // Read it back on the "next request".
+        $session = new Store('test', $handler, $sessionId, 'json');
+        $session->start();
+
+        $this->assertSame(
+            [['message' => 'Saved!', 'type' => 'success', 'duration' => null]],
+            (new Manager($session))->toArray()
+        );
+    }
+}