diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5f3ce76..e172c4e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,12 @@ See [GitHub releases](https://github.com/mll-lab/laravel-utils/releases).
 
 ## Unreleased
 
+## v5.2.1
+
+### Fixed
+
+- Handle `null` in `UnsignedInt` cast
+
 ## v5.2.0
 
 ### Added
diff --git a/src/Casts/UnsignedInt.php b/src/Casts/UnsignedInt.php
index 4339352..c2cc410 100644
--- a/src/Casts/UnsignedInt.php
+++ b/src/Casts/UnsignedInt.php
@@ -19,7 +19,7 @@ class UnsignedInt implements CastsAttributes
      * @param  string  $key
      * @param  array<array-key, mixed> $attributes
      */
-    public function get($model, $key, $value, $attributes): int
+    public function get($model, $key, $value, $attributes): ?int
     {
         return $this->cast($value);
     }
@@ -29,13 +29,17 @@ public function get($model, $key, $value, $attributes): int
      * @param  string  $key
      * @param  array<array-key, mixed>  $attributes
      */
-    public function set($model, $key, $value, $attributes): int
+    public function set($model, $key, $value, $attributes): ?int
     {
         return $this->cast($value);
     }
 
-    protected function cast(mixed $value): int
+    protected function cast(mixed $value): ?int
     {
+        if ($value === null) {
+            return null;
+        }
+
         if (is_float($value)) {
             $value = (int) round($value);
         }
diff --git a/tests/Casts/UnsignedIntTest.php b/tests/Casts/UnsignedIntTest.php
index 8317f79..00409a9 100644
--- a/tests/Casts/UnsignedIntTest.php
+++ b/tests/Casts/UnsignedIntTest.php
@@ -9,8 +9,13 @@ final class UnsignedIntTest extends TestCase
     public function testCast(): void
     {
         $model = new CastsModel();
+
+        $model->setRawAttribute('unsigned_int', null);
         self::assertNull($model->unsigned_int);
 
+        $model->unsigned_int = null;
+        self::assertNull($model->getRawAttribute('unsigned_int'));
+
         $model->unsigned_int = -1;
         self::assertSame(0, $model->getRawAttribute('unsigned_int'));
 
@@ -35,7 +40,7 @@ public function testCast(): void
         $model->setRawAttribute('unsigned_int', 1.1);
         self::assertSame(1, $model->unsigned_int);
 
-        $this->expectExceptionObject(new \RuntimeException('Expected int, got string: "foo".'));
+        $this->expectExceptionObject(new \RuntimeException("Expected int, got string: 'foo'."));
         $model->unsigned_int = 'foo'; // @phpstan-ignore-line intentionally wrong
     }
 }