diff --git a/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/narrower_property_type.php.inc b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/narrower_property_type.php.inc
new file mode 100644
index 00000000000..570e1a2f252
--- /dev/null
+++ b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/narrower_property_type.php.inc
@@ -0,0 +1,28 @@
+<?php
+
+namespace Rector\Tests\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector\Fixture;
+
+final class NarrowerPropertyType
+{
+    private object $entity;
+
+    public function __construct(?object $entity)
+    {
+        $this->entity = $entity;
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector\Fixture;
+
+final class NarrowerPropertyType
+{
+    public function __construct(private object $entity)
+    {
+    }
+}
+
+?>
diff --git a/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/skip_wider_property_type.php.inc b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/skip_wider_property_type.php.inc
new file mode 100644
index 00000000000..086a63a54ea
--- /dev/null
+++ b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/skip_wider_property_type.php.inc
@@ -0,0 +1,18 @@
+<?php
+
+namespace Rector\Tests\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector\Fixture;
+
+final class SkipWiderPropertyType
+{
+    private(set) ?object $entity;
+
+    public function __construct(object $entity)
+    {
+        $this->entity = $entity;
+    }
+
+    public function clear(): void
+    {
+        $this->entity = null;
+    }
+}
diff --git a/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/wider_property_type_without_null_assign.php.inc b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/wider_property_type_without_null_assign.php.inc
new file mode 100644
index 00000000000..35672d1c57b
--- /dev/null
+++ b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/wider_property_type_without_null_assign.php.inc
@@ -0,0 +1,30 @@
+<?php
+
+namespace Rector\Tests\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector\Fixture;
+
+final class WiderPropertyTypeWithoutNullAssign
+{
+    private(set) ?object $entity;
+
+    public function __construct(object $entity)
+    {
+        $this->entity = $entity;
+    }
+
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector\Fixture;
+
+final class WiderPropertyTypeWithoutNullAssign
+{
+    public function __construct(private(set) object $entity)
+    {
+    }
+
+}
+
+?>
diff --git a/rules/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector.php b/rules/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector.php
index 7e26ea9b871..079948aaaae 100644
--- a/rules/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector.php
+++ b/rules/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector.php
@@ -6,6 +6,7 @@
 
 use PhpParser\Node;
 use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\Assign;
 use PhpParser\Node\Expr\PropertyFetch;
 use PhpParser\Node\Expr\Variable;
 use PhpParser\Node\FunctionLike;
@@ -35,6 +36,7 @@
 use Rector\Php80\DocBlock\PropertyPromotionDocBlockMerger;
 use Rector\Php80\Guard\MakePropertyPromotionGuard;
 use Rector\Php80\NodeAnalyzer\PromotedPropertyCandidateResolver;
+use Rector\PhpParser\Node\BetterNodeFinder;
 use Rector\PhpParser\Node\Value\ValueResolver;
 use Rector\PHPStanStaticTypeMapper\Enum\TypeKind;
 use Rector\Rector\AbstractRector;
@@ -98,6 +100,7 @@ public function __construct(
         private readonly PhpDocInfoFactory $phpDocInfoFactory,
         private readonly StaticTypeMapper $staticTypeMapper,
         private readonly ValueResolver $valueResolver,
+        private readonly BetterNodeFinder $betterNodeFinder,
     ) {
     }
 
@@ -220,6 +223,10 @@ public function refactor(Node $node): ?Node
                 continue;
             }
 
+            if ($this->shouldSkipPropertyAssignedNull($node, $propertyName)) {
+                continue;
+            }
+
             $hasChanged = true;
 
             // remove property from class
@@ -477,6 +484,45 @@ private function shouldUsePropertyTypeForPromotedParam(Property $property, Param
         $paramType = $this->staticTypeMapper->mapPhpParserNodePHPStanType($param->type);
         $paramTypeWithoutNull = TypeCombinator::removeNull($paramType);
 
-        return $this->typeComparator->areTypesEqual($type, $paramTypeWithoutNull);
+        if (! $this->typeComparator->areTypesEqual($type, $paramTypeWithoutNull)) {
+            return false;
+        }
+
+        if ($param->default instanceof Expr) {
+            $paramType = TypeCombinator::union($paramType, $this->getType($param->default));
+        }
+
+        if ($this->typeComparator->isSubtype($paramType, $propertyType)
+            && ! $this->typeComparator->areTypesEqual($propertyType, $paramType)) {
+            return false;
+        }
+
+        return true;
+    }
+
+    private function shouldSkipPropertyAssignedNull(Class_ $class, string $propertyName): bool
+    {
+        return (bool) $this->betterNodeFinder->findFirst(
+            $class,
+            function (Node $node) use ($propertyName): bool {
+                if (! $node instanceof Assign) {
+                    return false;
+                }
+
+                if (! $node->var instanceof PropertyFetch) {
+                    return false;
+                }
+
+                if (! $this->isName($node->var->var, 'this')) {
+                    return false;
+                }
+
+                if (! $this->isName($node->var->name, $propertyName)) {
+                    return false;
+                }
+
+                return $this->valueResolver->isNull($node->expr);
+            }
+        );
     }
 }