diff --git a/src/Generator/Php.php b/src/Generator/Php.php
index ced3b20a..9631bc00 100644
--- a/src/Generator/Php.php
+++ b/src/Generator/Php.php
@@ -158,6 +158,8 @@ protected function writeStruct(Code\Name $name, array $properties, ?string $exte
                 $prop->addAttribute($attribute);
             }
 
+            $prop->setDefault(null);
+
             $class->addStmt($prop);
 
             $setter = $this->factory->method($property->getName()->getMethod(prefix: ['set']));
diff --git a/tests/Generator/resource/php/php.php b/tests/Generator/resource/php/php.php
index d7cb8216..c69cb41e 100644
--- a/tests/Generator/resource/php/php.php
+++ b/tests/Generator/resource/php/php.php
@@ -3,8 +3,8 @@
 #[Description('Location of the person')]
 class Location implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?float $lat;
-    protected ?float $long;
+    protected ?float $lat = null;
+    protected ?float $long = null;
     public function setLat(?float $lat) : void
     {
         $this->lat = $lat;
@@ -41,20 +41,20 @@ public function jsonSerialize() : object
 #[Description('An simple author element with some description')]
 class Author implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?string $title;
+    protected ?string $title = null;
     #[Description('We will send no spam to this address')]
     #[Nullable(true)]
-    protected ?string $email;
+    protected ?string $email = null;
     /**
      * @var array<string>|null
      */
-    protected ?array $categories;
+    protected ?array $categories = null;
     /**
      * @var array<Location>|null
      */
     #[Description('Array of locations')]
-    protected ?array $locations;
-    protected ?Location $origin;
+    protected ?array $locations = null;
+    protected ?Location $origin = null;
     public function setTitle(?string $title) : void
     {
         $this->title = $title;
@@ -138,47 +138,47 @@ class Meta extends \ArrayObject
 #[Description('An general news entry')]
 class News implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?Meta $config;
+    protected ?Meta $config = null;
     /**
      * @var \PSX\Record\Record|null
      */
-    protected ?\PSX\Record\Record $inlineConfig;
+    protected ?\PSX\Record\Record $inlineConfig = null;
     /**
      * @var \PSX\Record\Record|null
      */
-    protected ?\PSX\Record\Record $mapTags;
+    protected ?\PSX\Record\Record $mapTags = null;
     /**
      * @var \PSX\Record\Record|null
      */
-    protected ?\PSX\Record\Record $mapReceiver;
+    protected ?\PSX\Record\Record $mapReceiver = null;
     /**
      * @var array<string>|null
      */
-    protected ?array $tags;
+    protected ?array $tags = null;
     /**
      * @var array<Author>|null
      */
-    protected ?array $receiver;
-    protected ?bool $read;
-    protected ?Author $author;
-    protected ?Meta $meta;
+    protected ?array $receiver = null;
+    protected ?bool $read = null;
+    protected ?Author $author = null;
+    protected ?Meta $meta = null;
     #[Format('date')]
-    protected ?\PSX\DateTime\LocalDate $sendDate;
+    protected ?\PSX\DateTime\LocalDate $sendDate = null;
     #[Format('date-time')]
-    protected ?\PSX\DateTime\LocalDateTime $readDate;
-    protected ?float $price;
-    protected ?int $rating;
+    protected ?\PSX\DateTime\LocalDateTime $readDate = null;
+    protected ?float $price = null;
+    protected ?int $rating = null;
     #[Description('Contains the main content of the news entry')]
-    protected ?string $content;
-    protected ?string $question;
-    protected ?string $version;
+    protected ?string $content = null;
+    protected ?string $question = null;
+    protected ?string $version = null;
     #[Format('time')]
-    protected ?\PSX\DateTime\LocalTime $coffeeTime;
+    protected ?\PSX\DateTime\LocalTime $coffeeTime = null;
     #[Key('g-recaptcha-response')]
-    protected ?string $captcha;
+    protected ?string $captcha = null;
     #[Key('media.fields')]
-    protected ?string $mediaFields;
-    protected mixed $payload;
+    protected ?string $mediaFields = null;
+    protected mixed $payload = null;
     public function setConfig(?Meta $config) : void
     {
         $this->config = $config;
diff --git a/tests/Generator/resource/php/php_complex.php b/tests/Generator/resource/php/php_complex.php
index 0fcb6583..d277093b 100644
--- a/tests/Generator/resource/php/php_complex.php
+++ b/tests/Generator/resource/php/php_complex.php
@@ -10,11 +10,11 @@
 abstract class DefinitionType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $description;
+    protected ?string $description = null;
     #[Description('')]
-    protected ?bool $deprecated;
+    protected ?bool $deprecated = null;
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setDescription(?string $description) : void
     {
         $this->description = $description;
@@ -60,28 +60,28 @@ public function jsonSerialize() : object
 class StructDefinitionType extends DefinitionType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     #[Description('The parent type of this struct. The struct inherits all properties from the parent type')]
-    protected ?string $parent;
+    protected ?string $parent = null;
     #[Description('Indicates that this struct is a base type, this means it is an abstract type which is used by different types as parent')]
-    protected ?bool $base;
+    protected ?bool $base = null;
     /**
      * @var \PSX\Record\Record|null
      */
     #[Description('')]
-    protected ?\PSX\Record\Record $properties;
+    protected ?\PSX\Record\Record $properties = null;
     #[Description('In case this is a base type it is possible to specify a discriminator property')]
-    protected ?string $discriminator;
+    protected ?string $discriminator = null;
     /**
      * @var \PSX\Record\Record|null
      */
     #[Description('In case a discriminator property was set it is possible to specify a mapping. The key is the type name and the value the concrete value which is mapped to the type')]
-    protected ?\PSX\Record\Record $mapping;
+    protected ?\PSX\Record\Record $mapping = null;
     /**
      * @var \PSX\Record\Record|null
      */
     #[Description('In case the parent type contains generics it is possible to set a concrete type for each generic type')]
-    protected ?\PSX\Record\Record $template;
+    protected ?\PSX\Record\Record $template = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -168,9 +168,9 @@ public function jsonSerialize() : object
 abstract class CollectionDefinitionType extends DefinitionType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     #[Description('')]
-    protected ?PropertyType $schema;
+    protected ?PropertyType $schema = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -207,7 +207,7 @@ public function jsonSerialize() : object
 class MapDefinitionType extends CollectionDefinitionType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -235,7 +235,7 @@ public function jsonSerialize() : object
 class ArrayDefinitionType extends CollectionDefinitionType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -275,13 +275,13 @@ public function jsonSerialize() : object
 abstract class PropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $description;
+    protected ?string $description = null;
     #[Description('')]
-    protected ?bool $deprecated;
+    protected ?bool $deprecated = null;
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     #[Description('')]
-    protected ?bool $nullable;
+    protected ?bool $nullable = null;
     public function setDescription(?string $description) : void
     {
         $this->description = $description;
@@ -343,7 +343,7 @@ public function jsonSerialize() : object
 abstract class ScalarPropertyType extends PropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -371,7 +371,7 @@ public function jsonSerialize() : object
 class IntegerPropertyType extends ScalarPropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -399,7 +399,7 @@ public function jsonSerialize() : object
 class NumberPropertyType extends ScalarPropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -427,9 +427,9 @@ public function jsonSerialize() : object
 class StringPropertyType extends ScalarPropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     #[Description('')]
-    protected ?string $format;
+    protected ?string $format = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -466,7 +466,7 @@ public function jsonSerialize() : object
 class BooleanPropertyType extends ScalarPropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -499,9 +499,9 @@ public function jsonSerialize() : object
 abstract class CollectionPropertyType extends PropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     #[Description('')]
-    protected ?PropertyType $schema;
+    protected ?PropertyType $schema = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -538,7 +538,7 @@ public function jsonSerialize() : object
 class MapPropertyType extends CollectionPropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -566,7 +566,7 @@ public function jsonSerialize() : object
 class ArrayPropertyType extends CollectionPropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -594,7 +594,7 @@ public function jsonSerialize() : object
 class AnyPropertyType extends PropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -622,9 +622,9 @@ public function jsonSerialize() : object
 class GenericPropertyType extends PropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     #[Description('The generic name, it is recommended to use typical generics names like T or TValue')]
-    protected ?string $name;
+    protected ?string $name = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -661,9 +661,9 @@ public function jsonSerialize() : object
 class ReferencePropertyType extends PropertyType implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
     #[Description('')]
-    protected ?string $type;
+    protected ?string $type = null;
     #[Description('Name of the target reference, must a key from the definitions map')]
-    protected ?string $target;
+    protected ?string $target = null;
     public function setType(?string $type) : void
     {
         $this->type = $type;
@@ -703,14 +703,14 @@ class Specification implements \JsonSerializable, \PSX\Record\RecordableInterfac
      * @var \PSX\Record\Record|null
      */
     #[Description('')]
-    protected ?\PSX\Record\Record $import;
+    protected ?\PSX\Record\Record $import = null;
     /**
      * @var \PSX\Record\Record|null
      */
     #[Description('')]
-    protected ?\PSX\Record\Record $definitions;
+    protected ?\PSX\Record\Record $definitions = null;
     #[Description('')]
-    protected ?string $root;
+    protected ?string $root = null;
     public function setImport(?\PSX\Record\Record $import) : void
     {
         $this->import = $import;
diff --git a/tests/Generator/resource/php/php_import.php b/tests/Generator/resource/php/php_import.php
index 13088fcc..0c6abf16 100644
--- a/tests/Generator/resource/php/php_import.php
+++ b/tests/Generator/resource/php/php_import.php
@@ -1,7 +1,7 @@
 class Import implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?StudentMap $students;
-    protected ?Student $student;
+    protected ?StudentMap $students = null;
+    protected ?Student $student = null;
     public function setStudents(?StudentMap $students) : void
     {
         $this->students = $students;
diff --git a/tests/Generator/resource/php/php_import_ns.php b/tests/Generator/resource/php/php_import_ns.php
index 71136534..1647e499 100644
--- a/tests/Generator/resource/php/php_import_ns.php
+++ b/tests/Generator/resource/php/php_import_ns.php
@@ -3,8 +3,8 @@
 
 class Import implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?\My\Import\StudentMap $students;
-    protected ?\My\Import\Student $student;
+    protected ?\My\Import\StudentMap $students = null;
+    protected ?\My\Import\Student $student = null;
     public function setStudents(?\My\Import\StudentMap $students) : void
     {
         $this->students = $students;
diff --git a/tests/Generator/resource/php/php_oop.php b/tests/Generator/resource/php/php_oop.php
index 8612a696..ffc6fb7e 100644
--- a/tests/Generator/resource/php/php_oop.php
+++ b/tests/Generator/resource/php/php_oop.php
@@ -1,7 +1,7 @@
 class Human implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?string $firstName;
-    protected ?Human $parent;
+    protected ?string $firstName = null;
+    protected ?Human $parent = null;
     public function setFirstName(?string $firstName) : void
     {
         $this->firstName = $firstName;
@@ -34,7 +34,7 @@ public function jsonSerialize() : object
 
 class Student extends Human implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?string $matricleNumber;
+    protected ?string $matricleNumber = null;
     public function setMatricleNumber(?string $matricleNumber) : void
     {
         $this->matricleNumber = $matricleNumber;
@@ -61,11 +61,11 @@ public function jsonSerialize() : object
  */
 class Map implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?int $totalResults;
+    protected ?int $totalResults = null;
     /**
      * @var array<T>|null
      */
-    protected ?array $entries;
+    protected ?array $entries = null;
     public function setTotalResults(?int $totalResults) : void
     {
         $this->totalResults = $totalResults;
@@ -111,7 +111,7 @@ class StudentMap extends Map implements \JsonSerializable, \PSX\Record\Recordabl
 
 class RootSchema implements \JsonSerializable, \PSX\Record\RecordableInterface
 {
-    protected ?StudentMap $students;
+    protected ?StudentMap $students = null;
     public function setStudents(?StudentMap $students) : void
     {
         $this->students = $students;