diff --git a/src/Model/Fields/Recurring/Schedule/AnchorDay.php b/src/Model/Fields/Recurring/Schedule/AnchorDay.php
new file mode 100644
index 0000000..01b99ab
--- /dev/null
+++ b/src/Model/Fields/Recurring/Schedule/AnchorDay.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace Tpay\OpenApi\Model\Fields\Recurring\Schedule;
+
+use Tpay\OpenApi\Model\Fields\Field;
+
+/**
+ * @method getValue(): int
+ */
+class AnchorDay extends Field
+{
+    protected $name = __CLASS__;
+    protected $type = self::INT;
+    protected $minimum = 1;
+    protected $maximum = 31;
+
+    public function checkMinimum($value)
+    {
+        if (is_null($value)) {
+            return;
+        }
+
+        parent::checkMinimum($value);
+    }
+}
diff --git a/src/Model/Objects/Recurring/Schedule.php b/src/Model/Objects/Recurring/Schedule.php
index 9f0d14c..befbf00 100644
--- a/src/Model/Objects/Recurring/Schedule.php
+++ b/src/Model/Objects/Recurring/Schedule.php
@@ -3,6 +3,7 @@
 namespace Tpay\OpenApi\Model\Objects\Recurring;
 
 use Tpay\OpenApi\Model\Fields\Recurring\Schedule\Amount;
+use Tpay\OpenApi\Model\Fields\Recurring\Schedule\AnchorDay;
 use Tpay\OpenApi\Model\Fields\Recurring\Schedule\ChargeCount;
 use Tpay\OpenApi\Model\Fields\Recurring\Schedule\Currency;
 use Tpay\OpenApi\Model\Fields\Recurring\Schedule\FirstChargeDate;
@@ -20,6 +21,7 @@ class Schedule extends Objects
         'intervalType' => IntervalType::class,
         'chargeCount' => ChargeCount::class,
         'retryIntervals' => [RetryInterval::class],
+        'anchorDay' => AnchorDay::class,
     ];
 
     /** @var Amount */
@@ -43,6 +45,9 @@ class Schedule extends Objects
     /** @var RetryInterval */
     public $retryIntervals;
 
+    /** @var AnchorDay */
+    public $anchorDay;
+
     public function getRequiredFields()
     {
         return [
diff --git a/tests/Api/Recurring/RecurringApiTest.php b/tests/Api/Recurring/RecurringApiTest.php
index b841bdb..9e8a4a6 100644
--- a/tests/Api/Recurring/RecurringApiTest.php
+++ b/tests/Api/Recurring/RecurringApiTest.php
@@ -2,6 +2,7 @@
 
 namespace Tpay\Tests\OpenApi\Api\Recurring;
 
+use InvalidArgumentException;
 use PHPUnit\Framework\TestCase;
 use Tpay\OpenApi\Api\Recurring\RecurringApi;
 use Tpay\OpenApi\Model\Fields\Token\AccessToken;
@@ -93,6 +94,59 @@ public function testUpdatePaymentInstrumentInProductionModeAllowsTestPaymentType
         self::assertSame('ok', $result);
     }
 
+    public function testCreateRecurringAcceptsAnchorDayInSchedule()
+    {
+        CurlMock::setConsecutiveReturnedTransfers('"ok"');
+
+        $result = $this->createRecurringApi(false)->createRecurring($this->recurringFields(28));
+
+        self::assertSame('ok', $result);
+    }
+
+    public function testCreateRecurringAcceptsNullAnchorDayInSchedule()
+    {
+        CurlMock::setConsecutiveReturnedTransfers('"ok"');
+
+        $result = $this->createRecurringApi(false)->createRecurring($this->recurringFields(null));
+
+        self::assertSame('ok', $result);
+    }
+
+    public function testCreateRecurringDoesNotAllowAnchorDayOutOfRange()
+    {
+        CurlMock::expectNoCurlExecCall();
+
+        $this->expectException(InvalidArgumentException::class);
+
+        $this->createRecurringApi(false)->createRecurring($this->recurringFields(32));
+    }
+
+    /** @param null|int $anchorDay */
+    private function recurringFields($anchorDay)
+    {
+        return [
+            'id' => 'rec_12345678901234567890AB',
+            'description' => 'Recurring Order AB-CD-12',
+            'payer' => [
+                'email' => 'jan.kowalski@example.com',
+                'name' => 'Jan Kowalski',
+            ],
+            'schedule' => [
+                'amount' => 12.34,
+                'currency' => 'PLN',
+                'firstChargeDate' => '2025-11-12T12:34:00+02:00',
+                'interval' => 1,
+                'intervalType' => 'months',
+                'anchorDay' => $anchorDay,
+            ],
+            'paymentInstrument' => [
+                'paymentType' => 'card_token',
+                'value' => 'card-token-value',
+            ],
+            'callbackUrl' => 'https://example.com/callback',
+        ];
+    }
+
     private function createRecurringApi($productionMode)
     {
         $accessToken = $this->createMock(AccessToken::class);