diff --git a/app/code/Magento/QuoteGraphQl/Model/Cart/PlaceOrder.php b/app/code/Magento/QuoteGraphQl/Model/Cart/PlaceOrder.php
index b1a7ed3bdc5b6..0aed9fe1dabde 100644
--- a/app/code/Magento/QuoteGraphQl/Model/Cart/PlaceOrder.php
+++ b/app/code/Magento/QuoteGraphQl/Model/Cart/PlaceOrder.php
@@ -1,7 +1,7 @@
 <?php
 /**
- * Copyright © Magento, Inc. All rights reserved.
- * See COPYING.txt for license details.
+ * Copyright 2015 Adobe
+ * All Rights Reserved.
  */
 declare(strict_types=1);
 
@@ -12,6 +12,8 @@
 use Magento\Quote\Api\CartManagementInterface;
 use Magento\Quote\Api\PaymentMethodManagementInterface;
 use Magento\Quote\Model\Quote;
+use Psr\Log\LoggerInterface;
+use Magento\Framework\App\ObjectManager;
 
 /**
  * Place an order
@@ -28,16 +30,25 @@ class PlaceOrder
      */
     private $cartManagement;
 
+    /**
+     * @var LoggerInterface
+     */
+    private LoggerInterface $logger;
+
     /**
      * @param PaymentMethodManagementInterface $paymentManagement
      * @param CartManagementInterface $cartManagement
+     * @param LoggerInterface|null $logger
      */
     public function __construct(
         PaymentMethodManagementInterface $paymentManagement,
-        CartManagementInterface $cartManagement
+        CartManagementInterface $cartManagement,
+        ?LoggerInterface $logger = null
     ) {
         $this->paymentManagement = $paymentManagement;
         $this->cartManagement = $cartManagement;
+        $this->logger = $logger ?: ObjectManager::getInstance()
+            ->get(LoggerInterface::class);
     }
 
     /**
@@ -58,6 +69,36 @@ public function execute(Quote $cart, string $maskedCartId, int $userId): int
         $cartId = (int)$cart->getId();
         $paymentMethod = $this->paymentManagement->get($cartId);
 
+        // Get a list of available payment methods for the cart
+        $availablePaymentMethods = $this->paymentManagement->getList($cartId);
+        $payment = $cart->getPayment();
+        $paymentMethodCode = $payment?->getMethod();
+        // Check if the selected payment method is in the available methods list
+        if ($paymentMethodCode && $availablePaymentMethods) {
+            $availableCodes = array_map(fn($method) => $method->getCode(), $availablePaymentMethods);
+            $isPaymentMethodAvailable = in_array($paymentMethodCode, $availableCodes);
+        } else {
+            $isPaymentMethodAvailable = false;
+        }
+
+        if (!$isPaymentMethodAvailable) {
+            // Log the attempt to use a disabled payment method
+            $this->logger->debug(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => $paymentMethodCode,
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => $availablePaymentMethods ?
+                        array_map(fn($method) => $method->getCode(), $availablePaymentMethods) : []
+                ]
+            );
+
+            throw new LocalizedException(
+                __('The requested Payment Method \'%1\' is not available.', $paymentMethodCode ?: 'unknown')
+            );
+        }
+
         return (int)$this->cartManagement->placeOrder($cartId, $paymentMethod);
     }
 }
diff --git a/app/code/Magento/QuoteGraphQl/Test/Unit/Model/Cart/PlaceOrderTest.php b/app/code/Magento/QuoteGraphQl/Test/Unit/Model/Cart/PlaceOrderTest.php
new file mode 100644
index 0000000000000..e7e9d31f6be97
--- /dev/null
+++ b/app/code/Magento/QuoteGraphQl/Test/Unit/Model/Cart/PlaceOrderTest.php
@@ -0,0 +1,469 @@
+<?php
+/**
+ * Copyright 2025 Adobe
+ * All Rights Reserved.
+ */
+declare(strict_types=1);
+
+namespace Magento\QuoteGraphQl\Test\Unit\Model\Cart;
+
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Framework\Exception\NoSuchEntityException;
+use Magento\Quote\Api\CartManagementInterface;
+use Magento\Quote\Api\Data\PaymentInterface;
+use Magento\Quote\Api\Data\PaymentMethodInterface;
+use Magento\Quote\Api\PaymentMethodManagementInterface;
+use Magento\Quote\Model\Quote;
+use Magento\Quote\Model\Quote\Payment;
+use Magento\QuoteGraphQl\Model\Cart\PlaceOrder;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Test for PlaceOrder
+ */
+class PlaceOrderTest extends TestCase
+{
+    /**
+     * @var PlaceOrder
+     */
+    private $placeOrder;
+
+    /**
+     * @var PaymentMethodManagementInterface|MockObject
+     */
+    private $paymentManagementMock;
+
+    /**
+     * @var CartManagementInterface|MockObject
+     */
+    private $cartManagementMock;
+
+    /**
+     * @var Quote|MockObject
+     */
+    private $quoteMock;
+
+    /**
+     * @var Payment|MockObject
+     */
+    private $paymentMock;
+
+    /**
+     * @var PaymentInterface|MockObject
+     */
+    private $paymentInterfaceMock;
+
+    /**
+     * @var LoggerInterface|MockObject
+     */
+    private $loggerMock;
+
+    /**
+     * Set up test environment
+     */
+    protected function setUp(): void
+    {
+        $this->paymentManagementMock = $this->createMock(PaymentMethodManagementInterface::class);
+        $this->cartManagementMock = $this->createMock(CartManagementInterface::class);
+        $this->quoteMock = $this->createMock(Quote::class);
+        $this->paymentMock = $this->createMock(Payment::class);
+        $this->paymentInterfaceMock = $this->createMock(PaymentInterface::class);
+        $this->loggerMock = $this->createMock(LoggerInterface::class);
+
+        $this->placeOrder = new PlaceOrder(
+            $this->paymentManagementMock,
+            $this->cartManagementMock,
+            $this->loggerMock
+        );
+    }
+
+    /**
+     * Test successful order placement with available payment method
+     */
+    public function testExecuteWithAvailablePaymentMethod(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+        $paymentMethodCode = 'checkmo';
+        $orderId = 789;
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn($paymentMethodCode);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $availableMethod1 = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod1->method('getCode')->willReturn('paypal');
+
+        $availableMethod2 = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod2->method('getCode')->willReturn($paymentMethodCode);
+
+        $availableMethod3 = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod3->method('getCode')->willReturn('stripe');
+
+        $availablePaymentMethods = [$availableMethod1, $availableMethod2, $availableMethod3];
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn($availablePaymentMethods);
+
+        $this->cartManagementMock->method('placeOrder')
+            ->with($cartId, $this->paymentInterfaceMock)
+            ->willReturn($orderId);
+
+        $result = $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+
+        $this->assertEquals($orderId, $result);
+    }
+
+    /**
+     * Test exception when payment method is not available
+     */
+    public function testExecuteWithUnavailablePaymentMethod(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+        $paymentMethodCode = 'unavailable_method';
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn($paymentMethodCode);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $availableMethod1 = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod1->method('getCode')->willReturn('paypal');
+
+        $availableMethod2 = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod2->method('getCode')->willReturn('stripe');
+
+        $availablePaymentMethods = [$availableMethod1, $availableMethod2];
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn($availablePaymentMethods);
+
+        $this->loggerMock->expects($this->once())
+            ->method('debug')
+            ->with(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => $paymentMethodCode,
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => ['paypal', 'stripe']
+                ]
+            );
+
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage("The requested Payment Method 'unavailable_method' is not available.");
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+
+    /**
+     * Test exception when no payment method is set on quote
+     */
+    public function testExecuteWithNoPaymentMethodSet(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn(null);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $availableMethod = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod->method('getCode')->willReturn('checkmo');
+        $availablePaymentMethods = [$availableMethod];
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn($availablePaymentMethods);
+
+        $this->loggerMock->expects($this->once())
+            ->method('debug')
+            ->with(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => null,
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => ['checkmo']
+                ]
+            );
+
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage("The requested Payment Method 'unknown' is not available.");
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+
+    /**
+     * Test exception when no payment methods are available
+     */
+    public function testExecuteWithNoAvailablePaymentMethods(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+        $paymentMethodCode = 'checkmo';
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn($paymentMethodCode);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn([]);
+
+        $this->loggerMock->expects($this->once())
+            ->method('debug')
+            ->with(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => $paymentMethodCode,
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => []
+                ]
+            );
+
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage("The requested Payment Method 'checkmo' is not available.");
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+
+    /**
+     * Test exception when available payment methods is null
+     */
+    public function testExecuteWithNullAvailablePaymentMethods(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+        $paymentMethodCode = 'checkmo';
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn($paymentMethodCode);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn(null);
+
+        $this->loggerMock->expects($this->once())
+            ->method('debug')
+            ->with(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => $paymentMethodCode,
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => []
+                ]
+            );
+
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage("The requested Payment Method 'checkmo' is not available.");
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+
+    /**
+     * Test exception when quote has no payment object
+     */
+    public function testExecuteWithNoPaymentObject(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn(null);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $availableMethod = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod->method('getCode')->willReturn('checkmo');
+        $availablePaymentMethods = [$availableMethod];
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn($availablePaymentMethods);
+
+        $this->loggerMock->expects($this->once())
+            ->method('debug')
+            ->with(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => null,
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => ['checkmo']
+                ]
+            );
+
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage("The requested Payment Method 'unknown' is not available.");
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+
+    /**
+     * Test that cart management exceptions are propagated
+     */
+    public function testExecuteWithCartManagementException(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+        $paymentMethodCode = 'checkmo';
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn($paymentMethodCode);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $availableMethod = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod->method('getCode')->willReturn($paymentMethodCode);
+        $availablePaymentMethods = [$availableMethod];
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn($availablePaymentMethods);
+
+        $expectedException = new NoSuchEntityException(__('Cart does not exist'));
+        $this->cartManagementMock->method('placeOrder')
+            ->with($cartId, $this->paymentInterfaceMock)
+            ->willThrowException($expectedException);
+
+        $this->expectException(NoSuchEntityException::class);
+        $this->expectExceptionMessage('Cart does not exist');
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+
+    /**
+     * Test with empty string payment method code
+     */
+    public function testExecuteWithEmptyPaymentMethodCode(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn('');
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $availableMethod = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod->method('getCode')->willReturn('checkmo');
+        $availablePaymentMethods = [$availableMethod];
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn($availablePaymentMethods);
+
+        $this->loggerMock->expects($this->once())
+            ->method('debug')
+            ->with(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => '',
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => ['checkmo']
+                ]
+            );
+
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage("The requested Payment Method 'unknown' is not available.");
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+
+    /**
+     * Test case sensitivity in payment method code comparison
+     */
+    public function testExecuteWithCaseSensitivePaymentMethodCode(): void
+    {
+        $cartId = 123;
+        $maskedCartId = 'masked123';
+        $userId = 456;
+        $paymentMethodCode = 'CheckMo'; // Different case
+
+        $this->quoteMock->method('getId')->willReturn($cartId);
+        $this->quoteMock->method('getPayment')->willReturn($this->paymentMock);
+
+        $this->paymentMock->method('getMethod')->willReturn($paymentMethodCode);
+
+        $this->paymentManagementMock->method('get')
+            ->with($cartId)
+            ->willReturn($this->paymentInterfaceMock);
+
+        $availableMethod = $this->createMock(PaymentMethodInterface::class);
+        $availableMethod->method('getCode')->willReturn('checkmo'); // lowercase
+        $availablePaymentMethods = [$availableMethod];
+
+        $this->paymentManagementMock->method('getList')
+            ->with($cartId)
+            ->willReturn($availablePaymentMethods);
+
+        $this->loggerMock->expects($this->once())
+            ->method('debug')
+            ->with(
+                'Attempt to place order with disabled payment method',
+                [
+                    'payment_method' => $paymentMethodCode,
+                    'cart_id' => $cartId,
+                    'user_id' => $userId,
+                    'available_methods' => ['checkmo']
+                ]
+            );
+
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage("The requested Payment Method 'CheckMo' is not available.");
+
+        $this->placeOrder->execute($this->quoteMock, $maskedCartId, $userId);
+    }
+}