diff --git a/lib/Client/Mailbox.php b/lib/Client/Mailbox.php
index c59e04b..0b3119d 100644
--- a/lib/Client/Mailbox.php
+++ b/lib/Client/Mailbox.php
@@ -26,13 +26,15 @@ final class Mailbox
 
     public function fromStatus(MailboxStatusResult $status): self
     {
+        $items = $status->items();
+
         return new self(
             $this->name,
             $this->delimiter,
             $this->attributes,
-            $status->messages() ?? $this->messages,
-            $status->unseen() ?? $this->unread,
-            $status->uidValidity() ?? $this->uidValidity,
+            $items['MESSAGES'] ?? $this->messages,
+            $items['UNSEEN'] ?? $this->unread,
+            $items['UIDVALIDITY'] ?? $this->uidValidity,
             $this->recent,
             $this->flags,
             $this->readOnly,
diff --git a/tests/php/Unit/MailboxTest.php b/tests/php/Unit/MailboxTest.php
new file mode 100644
index 0000000..6588ea7
--- /dev/null
+++ b/tests/php/Unit/MailboxTest.php
@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace KTXT\ProviderImap\Tests\Unit;
+
+use KTXM\ProviderImap\Client\Mailbox;
+use KTXM\ProviderImap\Client\Result\MailboxStatusResult;
+use PHPUnit\Framework\TestCase;
+
+final class MailboxTest extends TestCase
+{
+    public function testPartialStatusPreservesUnreportedValues(): void
+    {
+        $mailbox = new Mailbox('INBOX', '/', [], 12, 4, 123);
+
+        $updated = $mailbox->fromStatus(new MailboxStatusResult('INBOX', ['UNSEEN' => 2]));
+
+        $this->assertSame(12, $updated->messages());
+        $this->assertSame(2, $updated->unread());
+        $this->assertSame(123, $updated->uidValidity());
+        $this->assertSame(4, $mailbox->unread());
+    }
+
+    public function testExplicitZeroCountsReplaceKnownCounts(): void
+    {
+        $mailbox = new Mailbox('INBOX', '/', [], 12, 4, 123);
+
+        $updated = $mailbox->fromStatus(new MailboxStatusResult('INBOX', [
+            'MESSAGES' => 0,
+            'UNSEEN' => 0,
+            'UIDVALIDITY' => 456,
+        ]));
+
+        $this->assertSame(0, $updated->messages());
+        $this->assertSame(0, $updated->unread());
+        $this->assertSame(456, $updated->uidValidity());
+    }
+
+    public function testEmptyStatusPreservesMailboxIncludingUnknownUidValidity(): void
+    {
+        foreach ([null, 123] as $uidValidity) {
+            $mailbox = new Mailbox('INBOX', '/', ['\\HasNoChildren'], 12, 4, $uidValidity, 2, ['\\Seen'], false);
+
+            $updated = $mailbox->fromStatus(new MailboxStatusResult('INBOX', []));
+
+            $this->assertEquals($mailbox, $updated);
+        }
+    }
+}