diff --git a/app/Filament/Resources/OfftimeResource.php b/app/Filament/Resources/OfftimeResource.php
index b8bcd92..10c2c16 100644
--- a/app/Filament/Resources/OfftimeResource.php
+++ b/app/Filament/Resources/OfftimeResource.php
@@ -5,6 +5,7 @@
 use App\Enums\OfftimeCategory;
 use App\Filament\Resources\OfftimeResource\Pages\ListOfftimes;
 use App\Models\Offtime;
+use Carbon\Carbon;
 use Filament\Actions\ActionGroup;
 use Filament\Actions\BulkActionGroup;
 use Filament\Actions\CreateAction;
@@ -18,6 +19,8 @@
 use Filament\Resources\Resource;
 use Filament\Schemas\Components\Grid;
 use Filament\Schemas\Components\Section;
+use Filament\Schemas\Components\Utilities\Get;
+use Filament\Schemas\Components\Utilities\Set;
 use Filament\Schemas\Schema;
 use Filament\Support\Enums\FontFamily;
 use Filament\Support\Enums\Width;
@@ -133,12 +136,19 @@ public static function formFields(int $columns = 12, bool $useSection = true): a
                 ->weekStartsOnMonday()
                 ->suffixIcon('tabler-calendar-dot')
                 ->columnSpan($columns / 2)
-                ->required(),
+                ->required()
+                ->live()
+                ->afterStateUpdated(function (?string $state, Get $get, Set $set) {
+                    if ($state && $get('end')) {
+                        $set('end', Carbon::parse($state)->addDay()->toDateString());
+                    }
+                }),
             DatePicker::make('end')
                 ->label(__('finished'))
                 ->weekStartsOnMonday()
                 ->columnSpan($columns / 2)
-                ->suffixIcon('tabler-calendar-pause'),
+                ->suffixIcon('tabler-calendar-pause')
+                ->after('start'),
             Select::make('category')
                 ->label(__('category'))
                 ->columnSpanFull()
diff --git a/database/factories/OfftimeFactory.php b/database/factories/OfftimeFactory.php
index eaf8de2..4841e58 100644
--- a/database/factories/OfftimeFactory.php
+++ b/database/factories/OfftimeFactory.php
@@ -26,7 +26,7 @@ class OfftimeFactory extends Factory
     public function definition(): array
     {
         $start = fake()->dateTimeBetween('-1 year', '+1 year');
-        $end = fake()->dateTimeBetween($start, (clone $start)->modify('+5 days'));
+        $end = fake()->dateTimeBetween((clone $start)->modify('+1 day'), (clone $start)->modify('+5 days'));
 
         return [
             'start' => $start->format('Y-m-d'),
diff --git a/tests/Feature/OfftimeResourceTest.php b/tests/Feature/OfftimeResourceTest.php
index 75dad86..bf152bf 100644
--- a/tests/Feature/OfftimeResourceTest.php
+++ b/tests/Feature/OfftimeResourceTest.php
@@ -82,6 +82,45 @@ public function it_requires_a_start_date_and_category_when_creating_an_offtime()
         $this->assertDatabaseCount('offtimes', 0);
     }
 
+    #[Test]
+    public function it_requires_the_end_date_to_be_after_the_start_date(): void
+    {
+        $this->actingAs(User::factory()->create());
+
+        Livewire::test(ListOfftimes::class)
+            ->callAction(CreateAction::class, data: [
+                'start' => '2026-01-10',
+                'end' => '2026-01-10',
+                'category' => OfftimeCategory::Vacation,
+            ])
+            ->assertHasFormErrors(['end' => 'after']);
+
+        $this->assertDatabaseCount('offtimes', 0);
+    }
+
+    #[Test]
+    public function it_sets_the_end_date_to_the_day_after_a_changed_start_date(): void
+    {
+        $this->actingAs(User::factory()->create());
+        $offtime = Offtime::factory()->create(['start' => '2026-01-01', 'end' => '2026-01-05']);
+
+        Livewire::test(ListOfftimes::class)
+            ->mountAction(TestAction::make(EditAction::class)->table($offtime))
+            ->fillForm(['start' => '2026-01-10'])
+            ->assertActionDataSet(['end' => '2026-01-11']);
+    }
+
+    #[Test]
+    public function it_keeps_the_end_date_empty_when_changing_the_start_date(): void
+    {
+        $this->actingAs(User::factory()->create());
+
+        Livewire::test(ListOfftimes::class)
+            ->mountAction(CreateAction::class)
+            ->fillForm(['start' => '2026-01-10'])
+            ->assertActionDataSet(['end' => null]);
+    }
+
     #[Test]
     public function it_updates_an_offtime(): void
     {