diff --git a/src/Model/Validator/ExtractedMethodValidator.php b/src/Model/Validator/ExtractedMethodValidator.php
index c1b8cc56..6a63b616 100644
--- a/src/Model/Validator/ExtractedMethodValidator.php
+++ b/src/Model/Validator/ExtractedMethodValidator.php
@@ -59,7 +59,7 @@ public function __construct(
             public function getCode(): string
             {
                 $renderHelper = new RenderHelper($this->generatorConfiguration);
-                return "private function {$this->validator->getExtractedMethodName()}(&\$value): void {
+                return "private function {$this->validator->getExtractedMethodName()}(&\$value, \$modelData): void {
                     {$this->validator->getValidatorSetUp()}
                     
                     if ({$this->validator->getCheck()}) {
diff --git a/src/PropertyProcessor/Property/ConstProcessor.php b/src/PropertyProcessor/Property/ConstProcessor.php
index 9ca86d8e..d5ad8097 100644
--- a/src/PropertyProcessor/Property/ConstProcessor.php
+++ b/src/PropertyProcessor/Property/ConstProcessor.php
@@ -10,7 +10,7 @@
 use PHPModelGenerator\Model\Property\PropertyType;
 use PHPModelGenerator\Model\SchemaDefinition\JsonSchema;
 use PHPModelGenerator\Model\Validator\PropertyValidator;
-use PHPModelGenerator\PropertyProcessor\PropertyProcessorInterface;
+use PHPModelGenerator\Utils\RenderHelper;
 use PHPModelGenerator\Utils\TypeConverter;
 
 /**
@@ -18,7 +18,7 @@
  *
  * @package PHPModelGenerator\PropertyProcessor\Property
  */
-class ConstProcessor implements PropertyProcessorInterface
+class ConstProcessor extends AbstractPropertyProcessor
 {
     /**
      * @inheritdoc
@@ -34,13 +34,26 @@ public function process(string $propertyName, JsonSchema $propertySchema): Prope
             $json['description'] ?? '',
         );
 
-        return $property
-            ->setRequired(true)
-            ->addValidator(new PropertyValidator(
-                $property,
-                '$value !== ' . var_export($json['const'], true),
-                InvalidConstException::class,
-                [$json['const']],
-            ));
+        $property->setRequired($this->propertyMetaDataCollection->isAttributeRequired($propertyName));
+
+        $check = match(true) {
+            $property->isRequired()
+                => '$value !== ' . var_export($json['const'], true),
+            $this->isImplicitNullAllowed($property)
+                => '!in_array($value, ' . RenderHelper::varExportArray([$json['const'], null]) . ', true)',
+            default
+                => "array_key_exists('{$property->getName()}', \$modelData) && \$value !== " . var_export($json['const'], true),
+        };
+
+        $property->addValidator(new PropertyValidator(
+            $property,
+            $check,
+            InvalidConstException::class,
+            [$json['const']],
+        ));
+
+        $this->generateValidators($property, $propertySchema);
+
+        return $property;
     }
 }
diff --git a/src/Templates/Validator/AdditionalProperties.phptpl b/src/Templates/Validator/AdditionalProperties.phptpl
index 87557485..96c93e64 100644
--- a/src/Templates/Validator/AdditionalProperties.phptpl
+++ b/src/Templates/Validator/AdditionalProperties.phptpl
@@ -1,4 +1,4 @@
-(function () use ($properties, &$invalidProperties) {
+(function () use ($properties, &$invalidProperties, $modelData) {
     {% if generatorConfiguration.collectErrors() %}
         $originalErrorRegistry = $this->_errorRegistry;
     {% endif %}
diff --git a/src/Templates/Validator/ArrayItem.phptpl b/src/Templates/Validator/ArrayItem.phptpl
index 0c14f334..cdbea591 100644
--- a/src/Templates/Validator/ArrayItem.phptpl
+++ b/src/Templates/Validator/ArrayItem.phptpl
@@ -1,4 +1,4 @@
-is_array($value) && (function (&$items) use (&$invalidItems{{ suffix }}) {
+is_array($value) && (function (&$items) use (&$invalidItems{{ suffix }}, $modelData) {
     {% if generatorConfiguration.collectErrors() %}
         $originalErrorRegistry = $this->_errorRegistry;
     {% endif %}
diff --git a/src/Templates/Validator/ArrayTuple.phptpl b/src/Templates/Validator/ArrayTuple.phptpl
index 425e9d11..d6ce49ea 100644
--- a/src/Templates/Validator/ArrayTuple.phptpl
+++ b/src/Templates/Validator/ArrayTuple.phptpl
@@ -1,4 +1,4 @@
-is_array($value) && (function (&$items) use (&$invalidTuples) {
+is_array($value) && (function (&$items) use (&$invalidTuples, $modelData) {
     {% if generatorConfiguration.collectErrors() %}
         $originalErrorRegistry = $this->_errorRegistry;
     {% endif %}
diff --git a/src/Templates/Validator/PatternProperties.phptpl b/src/Templates/Validator/PatternProperties.phptpl
index b69d4c13..42bb0094 100644
--- a/src/Templates/Validator/PatternProperties.phptpl
+++ b/src/Templates/Validator/PatternProperties.phptpl
@@ -1,4 +1,4 @@
-(function () use ($properties, &$invalidProperties) {
+(function () use ($properties, &$invalidProperties, $modelData) {
     {% if generatorConfiguration.collectErrors() %}
         $originalErrorRegistry = $this->_errorRegistry;
     {% endif %}
diff --git a/src/Utils/RenderHelper.php b/src/Utils/RenderHelper.php
index 4d249350..c69daaad 100644
--- a/src/Utils/RenderHelper.php
+++ b/src/Utils/RenderHelper.php
@@ -182,7 +182,7 @@ public function renderValidator(PropertyValidatorInterface $validator, Schema $s
             $schema->addMethod($validator->getExtractedMethodName(), $validator->getMethod());
         }
 
-        return "\$this->{$validator->getExtractedMethodName()}(\$value);";
+        return "\$this->{$validator->getExtractedMethodName()}(\$value, \$modelData);";
     }
 
     public function renderMethods(Schema $schema): string
diff --git a/tests/Objects/ConstPropertyTest.php b/tests/Objects/ConstPropertyTest.php
index 3f87ec06..e4a225ae 100644
--- a/tests/Objects/ConstPropertyTest.php
+++ b/tests/Objects/ConstPropertyTest.php
@@ -4,10 +4,15 @@
 
 namespace PHPModelGenerator\Tests\Objects;
 
+use PHPModelGenerator\Exception\Arrays\InvalidTupleException;
+use PHPModelGenerator\Exception\ComposedValue\OneOfException;
+use PHPModelGenerator\Exception\ErrorRegistryException;
 use PHPModelGenerator\Exception\FileSystemException;
+use PHPModelGenerator\Exception\Object\RequiredValueException;
 use PHPModelGenerator\Exception\ValidationException;
 use PHPModelGenerator\Exception\RenderException;
 use PHPModelGenerator\Exception\SchemaException;
+use PHPModelGenerator\Model\GeneratorConfiguration;
 use PHPModelGenerator\Tests\AbstractPHPModelGeneratorTestCase;
 use stdClass;
 
@@ -38,14 +43,38 @@ public function testProvidedConstPropertyIsValid(): void
      * @throws RenderException
      * @throws SchemaException
      */
-    public function testNotProvidedConstPropertyThrowsAnException(): void
+    public function testProvidedArrayItemConstPropertyIsValid(): void
     {
-        $this->expectException(ValidationException::class);
-        $this->expectExceptionMessage('Invalid value for stringProperty declined by const constraint');
+        $className = $this->generateClassFromFile('ArrayItemConstProperty.json');
 
-        $className = $this->generateClassFromFile('ConstProperty.json');
+        $object = new $className(['property' => ['red', 'red']]);
 
-        new $className([]);
+        $this->assertIsArray($object->getProperty());
+        $this->assertSame(['red', 'red'], $object->getProperty());
+    }
+
+    /**
+     * @dataProvider stringIntDataProvider
+     *
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testProvidedAnyOfConstPropertyIsValid(string|int $propertyValue): void
+    {
+        $className = $this->generateClassFromFile('AnyOfConstProperty.json');
+
+        $object = new $className(['property' => $propertyValue]);
+
+        $this->assertSame($propertyValue, $object->getProperty());
+    }
+
+    public function stringIntDataProvider(): array
+    {
+        return [
+            ['red'],
+            [1],
+        ];
     }
 
     /**
@@ -62,7 +91,7 @@ public function testNotMatchingProvidedDataThrowsAnException($propertyValue): vo
         $this->expectException(ValidationException::class);
         $this->expectExceptionMessage('Invalid value for stringProperty declined by const constraint');
 
-        $className = $this->generateClassFromFile('ConstProperty.json');
+        $className = $this->generateClassFromFile('ConstProperty.json', null, false, false);
 
         new $className(['stringProperty' => $propertyValue]);
     }
@@ -79,4 +108,170 @@ public function invalidPropertyDataProvider(): array
             'null' => [null],
         ];
     }
+
+    /**
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testNotMatchingArrayItemConstPropertyThrowsAnException(): void
+    {
+        $this->expectException(InvalidTupleException::class);
+        $this->expectExceptionMessage('Invalid tuple item in array property');
+
+        $className = $this->generateClassFromFile('ArrayItemConstProperty.json');
+
+        new $className(['property' => ['green']]);
+    }
+
+    /**
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testNotMatchingArrayItemConstPropertyThrowsAnException1(): void
+    {
+        $this->expectException(OneOfException::class);
+        $this->expectExceptionMessage('Invalid value for property declined by composition constraint');
+
+        $className = $this->generateClassFromFile('AnyOfConstProperty.json');
+
+        new $className(['property' => 'green']);
+    }
+
+    /**
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testProvidedConstOnlyRequiredPropertyIsValid(): void
+    {
+        $className = $this->generateClassFromFile('RequiredAndOptionalConstProperties.json');
+
+        $object = new $className(['requiredProperty' => 'red']);
+
+        $this->assertSame('red', $object->getRequiredProperty());
+        $this->assertNull($object->getOptionalProperty());
+    }
+
+    /**
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testProvidedNullOptionalPropertyConstPropertyIsValid(): void
+    {
+        $className = $this->generateClassFromFile('RequiredAndOptionalConstProperties.json');
+
+        $object = new $className(['requiredProperty' => 'red', 'optionalProperty' => null]);
+
+        $this->assertSame('red', $object->getRequiredProperty());
+        $this->assertNull($object->getOptionalProperty());
+    }
+
+    /**
+     * @dataProvider requiredAndOptionalPropertiesDataProvider
+     *
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testProvidedConstPropertiesIsValidWithDifferentImplicitNull(
+        bool $implicitNull,
+        string $reqPropertyValue,
+        string $optPropertyValue
+    ): void
+    {
+        $className = $this->generateClassFromFile(
+            'RequiredAndOptionalConstProperties.json',
+            new GeneratorConfiguration(),
+            false,
+            $implicitNull,
+        );
+
+        $object = new $className(['requiredProperty' => $reqPropertyValue, 'optionalProperty' => $optPropertyValue]);
+
+        $this->assertSame($reqPropertyValue, $object->getRequiredProperty());
+        $this->assertSame($optPropertyValue, $object->getOptionalProperty());
+    }
+
+    public function requiredAndOptionalPropertiesDataProvider(): array
+    {
+        return $this->combineDataProvider(
+            $this->implicitNullDataProvider(),
+            [
+                ['red', 'green'],
+            ],
+        );
+    }
+
+    /**
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testNotProvidedRequiredPropertyThrowsAnException(): void
+    {
+        $this->expectException(RequiredValueException::class);
+        $this->expectExceptionMessage('Missing required value for requiredProperty');
+
+        $className = $this->generateClassFromFile('RequiredAndOptionalConstProperties.json');
+
+        new $className([]);
+    }
+
+    /**
+     * @dataProvider invalidRequiredAndOptionalConstPropertiesDataProvider
+     *
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testNotMatchingRequiredAndOptionalProvidedDataThrowsAnException(
+        bool $implicitNull,
+        string $reqPropertyValue,
+        ?string $optPropertyValue,
+        string $exceptionMessage
+    ): void
+    {
+        $className = $this->generateClassFromFile(
+            'RequiredAndOptionalConstProperties.json',
+            new GeneratorConfiguration(),
+            false,
+            $implicitNull,
+        );
+
+        $this->expectException(ErrorRegistryException::class);
+        $this->expectExceptionMessage($exceptionMessage);
+
+        new $className(['requiredProperty' => $reqPropertyValue, 'optionalProperty' => $optPropertyValue]);
+    }
+
+    public function invalidRequiredAndOptionalConstPropertiesDataProvider(): array
+    {
+        return $this->combineDataProvider(
+            $this->implicitNullDataProvider(),
+            [
+                ['blue', 'green', 'Invalid value for requiredProperty declined by const constraint'],
+                ['blue', null, 'Invalid value for requiredProperty declined by const constraint'],
+                ['red', 'blue', 'Invalid value for optionalProperty declined by const constraint'],
+                ['red', '0', 'Invalid value for optionalProperty declined by const constraint'],
+                ['red', '', 'Invalid value for optionalProperty declined by const constraint'],
+            ],
+        );
+    }
+
+    /**
+     * @throws FileSystemException
+     * @throws RenderException
+     * @throws SchemaException
+     */
+    public function testProvidedNullValueConstPropertyIsValid(): void
+    {
+        $className = $this->generateClassFromFile('NullValueConstProperty.json', null, false, false);
+
+        $object = new $className(['nullProperty' => null]);
+
+        $this->assertNull($object->getNullProperty());
+    }
 }
diff --git a/tests/Schema/ConstPropertyTest/AnyOfConstProperty.json b/tests/Schema/ConstPropertyTest/AnyOfConstProperty.json
new file mode 100644
index 00000000..94d9539f
--- /dev/null
+++ b/tests/Schema/ConstPropertyTest/AnyOfConstProperty.json
@@ -0,0 +1,15 @@
+{
+  "type": "object",
+  "properties": {
+    "property": {
+      "oneOf": [
+        {
+          "const": "red"
+        },
+        {
+          "const": 1
+        }
+      ]
+    }
+  }
+}
\ No newline at end of file
diff --git a/tests/Schema/ConstPropertyTest/ArrayItemConstProperty.json b/tests/Schema/ConstPropertyTest/ArrayItemConstProperty.json
new file mode 100644
index 00000000..c111e74b
--- /dev/null
+++ b/tests/Schema/ConstPropertyTest/ArrayItemConstProperty.json
@@ -0,0 +1,13 @@
+{
+  "type": "object",
+  "properties": {
+    "property": {
+      "type": "array",
+      "items": [
+        {
+          "const": "red"
+        }
+      ]
+    }
+  }
+}
\ No newline at end of file
diff --git a/tests/Schema/ConstPropertyTest/NullValueConstProperty.json b/tests/Schema/ConstPropertyTest/NullValueConstProperty.json
new file mode 100644
index 00000000..8ee4dc45
--- /dev/null
+++ b/tests/Schema/ConstPropertyTest/NullValueConstProperty.json
@@ -0,0 +1,11 @@
+{
+  "type": "object",
+  "properties": {
+    "nullProperty": {
+      "const": null
+    }
+  },
+  "required": [
+    "nullProperty"
+  ]
+}
\ No newline at end of file
diff --git a/tests/Schema/ConstPropertyTest/RequiredAndOptionalConstProperties.json b/tests/Schema/ConstPropertyTest/RequiredAndOptionalConstProperties.json
new file mode 100644
index 00000000..06987a0a
--- /dev/null
+++ b/tests/Schema/ConstPropertyTest/RequiredAndOptionalConstProperties.json
@@ -0,0 +1,14 @@
+{
+  "type": "object",
+  "properties": {
+    "requiredProperty": {
+      "const": "red"
+    },
+    "optionalProperty": {
+      "const": "green"
+    }
+  },
+  "required": [
+    "requiredProperty"
+  ]
+}
\ No newline at end of file