diff --git a/src/Symfony/Component/Serializer/Serializer.php b/src/Symfony/Component/Serializer/Serializer.php
index e17042097fe3..9d0c45a6b0c4 100644
--- a/src/Symfony/Component/Serializer/Serializer.php
+++ b/src/Symfony/Component/Serializer/Serializer.php
@@ -222,7 +222,7 @@ public function denormalize(mixed $data, string $type, ?string $format = null, a
             throw new NotNormalizableValueException(sprintf('Could not denormalize object of type "%s", no supporting normalizer found.', $type));
         }
 
-        if (isset($context[DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS]) || isset($this->defaultContext[DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS])) {
+        if ((isset($context[DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS]) || isset($this->defaultContext[DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS])) && !isset($context['not_normalizable_value_exceptions'])) {
             unset($context[DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS]);
             $context['not_normalizable_value_exceptions'] = [];
             $errors = &$context['not_normalizable_value_exceptions'];
diff --git a/src/Symfony/Component/Serializer/Tests/SerializerTest.php b/src/Symfony/Component/Serializer/Tests/SerializerTest.php
index da5ccc15e439..b0dc887cea40 100644
--- a/src/Symfony/Component/Serializer/Tests/SerializerTest.php
+++ b/src/Symfony/Component/Serializer/Tests/SerializerTest.php
@@ -1677,6 +1677,54 @@ public function testCollectDenormalizationErrorsDefaultContext()
 
         $serializer->denormalize($data, DummyWithVariadicParameter::class);
     }
+
+    public function testDenormalizationFailsWithMultipleErrorsInDefaultContext()
+    {
+        $serializer = new Serializer(
+            [new DateTimeNormalizer(), new ObjectNormalizer()],
+            [],
+            [DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS => true]
+        );
+
+        $data = ['date' => '', 'unknown' => null];
+
+        try {
+            $serializer->denormalize($data, DummyEntityWithStringAndDateTime::class);
+            $this->fail('Expected PartialDenormalizationException was not thrown');
+        } catch (PartialDenormalizationException $e) {
+            $this->assertIsArray($e->getErrors());
+            $this->assertCount(2, $e->getErrors(), 'Expected two denormalization errors');
+
+            $exceptionsAsArray = array_map(function (NotNormalizableValueException $ex): array {
+                return [
+                    'currentType' => $ex->getCurrentType(),
+                    'expectedTypes' => $ex->getExpectedTypes(),
+                    'path' => $ex->getPath(),
+                    'useMessageForUser' => $ex->canUseMessageForUser(),
+                    'message' => $ex->getMessage(),
+                ];
+            }, $e->getErrors());
+
+            $expected = [
+                [
+                    'currentType' => 'null',
+                    'expectedTypes' => ['string'],
+                    'path' => 'bar',
+                    'useMessageForUser' => true,
+                    'message' => 'Failed to create object because the class misses the "bar" property.',
+                ],
+                [
+                    'currentType' => 'string',
+                    'expectedTypes' => ['string'],
+                    'path' => 'date',
+                    'useMessageForUser' => true,
+                    'message' => 'The data is either not an string, an empty string, or null; you should pass a string that can be parsed with the passed format or a valid DateTime string.',
+                ],
+            ];
+
+            $this->assertSame($expected, $exceptionsAsArray);
+        }
+    }
 }
 
 class Model
@@ -1743,6 +1791,15 @@ public function __construct($value)
     }
 }
 
+class DummyEntityWithStringAndDateTime
+{
+    public function __construct(
+        public string $bar,
+        public \DateTimeInterface $date,
+    ) {
+    }
+}
+
 class DummyUnionType
 {
     /**