diff --git a/app/Domains/Admin/Actions/UpdateTenantTax/UpdateTenantTaxRequest.php b/app/Domains/Admin/Actions/UpdateTenantTax/UpdateTenantTaxRequest.php
index 0361b7d..e02187b 100644
--- a/app/Domains/Admin/Actions/UpdateTenantTax/UpdateTenantTaxRequest.php
+++ b/app/Domains/Admin/Actions/UpdateTenantTax/UpdateTenantTaxRequest.php
@@ -9,12 +9,12 @@ use App\Models\Tenant;
 class UpdateTenantTaxRequest
 {
     public function __construct(
-        public Tenant              $tenant,
-        public bool                $taxLiable,
-        public int                 $vatRate,
+        public Tenant $tenant,
+        public bool $taxLiable,
+        public int $vatRate,
         public ?TaxExemptionReason $exemptionReason,
         public ?string $exemptionNote,
-        public VatPricingMode      $vatPricingMode,
+        public VatPricingMode $vatPricingMode,
     )
     {
     }
diff --git a/app/Domains/Admin/Controllers/ManagedTenantTaxUpdateController.php b/app/Domains/Admin/Controllers/ManagedTenantTaxUpdateController.php
index 691c939..5d6af6e 100644
--- a/app/Domains/Admin/Controllers/ManagedTenantTaxUpdateController.php
+++ b/app/Domains/Admin/Controllers/ManagedTenantTaxUpdateController.php
@@ -22,7 +22,7 @@ class ManagedTenantTaxUpdateController extends CommonController
             vatRate: (int)$request->input('vat_rate', 0),
             exemptionReason: TaxExemptionReason::where('slug', $request->input('tax_exemption_reason'))->first(),
             exemptionNote: $request->input('tax_exemption_note'),
-            vatPricingMode: VatPricingMode::tryFrom((string)$request->input('vat_pricing_mode', 'inclusive')) ?? VatPricingMode::Inclusive,
+            vatPricingMode: VatPricingMode::tryFrom((string) $request->input('vat_pricing_mode', 'inclusive')) ?? VatPricingMode::Inclusive,
         ));
 
         $response = $action->execute();
diff --git a/app/Domains/Admin/Controllers/TenantTaxUpdateController.php b/app/Domains/Admin/Controllers/TenantTaxUpdateController.php
index 1b2dea9..f8b17b8 100644
--- a/app/Domains/Admin/Controllers/TenantTaxUpdateController.php
+++ b/app/Domains/Admin/Controllers/TenantTaxUpdateController.php
@@ -20,7 +20,7 @@ class TenantTaxUpdateController extends CommonController
             vatRate: (int)$request->input('vat_rate', 0),
             exemptionReason: TaxExemptionReason::where('slug', $request->input('tax_exemption_reason'))->first(),
             exemptionNote: $request->input('tax_exemption_note'),
-            vatPricingMode: VatPricingMode::tryFrom((string)$request->input('vat_pricing_mode', 'inclusive')) ?? VatPricingMode::Inclusive,
+            vatPricingMode: VatPricingMode::tryFrom((string) $request->input('vat_pricing_mode', 'inclusive')) ?? VatPricingMode::Inclusive,
         ));
 
         $response = $action->execute();
diff --git a/app/Enumerations/TaxExemptionReason.php b/app/Enumerations/TaxExemptionReason.php
index a4af04e..10da598 100644
--- a/app/Enumerations/TaxExemptionReason.php
+++ b/app/Enumerations/TaxExemptionReason.php
@@ -44,7 +44,7 @@ class TaxExemptionReason extends CommonModel
      */
     public function invoiceText(?string $customNote = null): string
     {
-        return $this->requires_note ? trim((string)$customNote) : $this->invoice_text;
+        return $this->requires_note ? trim((string) $customNote) : $this->invoice_text;
     }
 
     /**
@@ -56,7 +56,7 @@ class TaxExemptionReason extends CommonModel
     public static function options(): array
     {
         return self::all()
-            ->map(static fn(self $reason): array => [
+            ->map(static fn (self $reason): array => [
                 'value' => $reason->slug,
                 'label' => $reason->name,
                 'text' => $reason->requires_note ? '' : $reason->invoice_text,
diff --git a/app/Enumerations/VatPricingMode.php b/app/Enumerations/VatPricingMode.php
new file mode 100644
index 0000000..ed5f9c0
--- /dev/null
+++ b/app/Enumerations/VatPricingMode.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace App\Enumerations;
+
+/**
+ * Preismodus bei bestehender Umsatzsteuerpflicht: entweder ist die USt bereits im konfigurierten Beitrag
+ * enthalten (Brutto/„Supermarkt") oder sie wird bei der Preisermittlung aufgeschlagen (Netto). Gespeichert
+ * wird immer der finale Brutto-Beitrag; der Modus beeinflusst nur die Preisermittlung im Anmeldeprozess.
+ */
+enum VatPricingMode: string
+{
+    case Inclusive = 'inclusive';
+    case AddOn = 'add_on';
+
+    public function label(): string
+    {
+        return match ($this) {
+            self::Inclusive => 'Inklusive – Beiträge sind Endpreise (USt enthalten)',
+            self::AddOn => 'Aufschlagen – USt wird auf die Beiträge aufgeschlagen',
+        };
+    }
+
+    /**
+     * Optionen für das Frontend: [['value' => ..., 'label' => ...], ...].
+     *
+     * @return array<int, array{value: string, label: string}>
+     */
+    public static function options(): array
+    {
+        return array_map(
+            static fn (self $mode): array => [
+                'value' => $mode->value,
+                'label' => $mode->label(),
+            ],
+            self::cases(),
+        );
+    }
+}
diff --git a/database/migrations/2026_08_06_160000_add_vat_pricing_mode_to_tenants.php b/database/migrations/2026_08_06_160000_add_vat_pricing_mode_to_tenants.php
new file mode 100644
index 0000000..c29dc62
--- /dev/null
+++ b/database/migrations/2026_08_06_160000_add_vat_pricing_mode_to_tenants.php
@@ -0,0 +1,21 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration {
+    public function up(): void
+    {
+        Schema::table('tenants', function (Blueprint $table) {
+            $table->string('vat_pricing_mode')->default('inclusive');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('tenants', function (Blueprint $table) {
+            $table->dropColumn('vat_pricing_mode');
+        });
+    }
+};
diff --git a/database/migrations/2026_08_06_160010_add_tax_snapshot_to_events.php b/database/migrations/2026_08_06_160010_add_tax_snapshot_to_events.php
new file mode 100644
index 0000000..8f3e5d9
--- /dev/null
+++ b/database/migrations/2026_08_06_160010_add_tax_snapshot_to_events.php
@@ -0,0 +1,36 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+/**
+ * Friert die umsatzsteuerliche Grundlage bei Event-Anlage aus den Tenant-Einstellungen ein. Die Werte sind
+ * danach unveränderlich, damit Preisermittlung und spätere Rechnungen von späteren Tenant-Änderungen
+ * unberührt bleiben. Bestandsevents erhalten die Defaults (keine USt).
+ */
+return new class extends Migration {
+    public function up(): void
+    {
+        Schema::table('events', function (Blueprint $table) {
+            $table->boolean('tax_liable')->default(false);
+            $table->unsignedTinyInteger('vat_rate')->default(0);
+            $table->string('vat_pricing_mode')->default('inclusive');
+            $table->string('tax_exemption_reason')->nullable();
+            $table->text('tax_exemption_note')->nullable();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('events', function (Blueprint $table) {
+            $table->dropColumn([
+                'tax_liable',
+                'vat_rate',
+                'vat_pricing_mode',
+                'tax_exemption_reason',
+                'tax_exemption_note',
+            ]);
+        });
+    }
+};
diff --git a/database/migrations/2026_08_06_170000_create_tax_exemption_reasons.php b/database/migrations/2026_08_06_170000_create_tax_exemption_reasons.php
new file mode 100644
index 0000000..114aeb9
--- /dev/null
+++ b/database/migrations/2026_08_06_170000_create_tax_exemption_reasons.php
@@ -0,0 +1,23 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration {
+    public function up(): void
+    {
+        Schema::create('tax_exemption_reasons', function (Blueprint $table) {
+            $table->string('slug')->primary();
+            $table->string('name');
+            $table->text('invoice_text')->nullable();
+            $table->boolean('requires_note')->default(false);
+            $table->timestamps();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('tax_exemption_reasons');
+    }
+};
diff --git a/database/migrations/2026_08_06_170010_add_tax_exemption_reason_foreign_keys.php b/database/migrations/2026_08_06_170010_add_tax_exemption_reason_foreign_keys.php
new file mode 100644
index 0000000..3360061
--- /dev/null
+++ b/database/migrations/2026_08_06_170010_add_tax_exemption_reason_foreign_keys.php
@@ -0,0 +1,48 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+/**
+ * Befüllt die Referenztabelle mit den Befreiungsgründen (§ 14 Abs. 4 Nr. 8 UStG) und verknüpft danach den
+ * nullbaren Befreiungsgrund von Tenant und Event per Foreign Key. Das Seeding erfolgt hier (nicht im
+ * ProductionDataSeeder), damit die FK-Ziele auch auf bestehenden Datenbanken beim Migrieren existieren.
+ * Ein noch nicht konfigurierter Tenant hat keinen Grund (NULL).
+ */
+return new class extends Migration {
+    public function up(): void
+    {
+        $now = now();
+        DB::table('tax_exemption_reasons')->insertOrIgnore([
+            ['slug' => 'small_business', 'name' => 'Kleinunternehmer (§ 19 UStG)', 'invoice_text' => 'Gemäß § 19 UStG wird keine Umsatzsteuer berechnet.', 'requires_note' => false, 'created_at' => $now, 'updated_at' => $now],
+            ['slug' => 'education', 'name' => 'Bildungs-/Kursleistung (§ 4 Nr. 22a UStG)', 'invoice_text' => 'Die Leistung ist gemäß § 4 Nr. 22 Buchst. a UStG von der Umsatzsteuer befreit.', 'requires_note' => false, 'created_at' => $now, 'updated_at' => $now],
+            ['slug' => 'youth_welfare', 'name' => 'Kinder- und Jugendhilfe (§ 4 Nr. 25 UStG)', 'invoice_text' => 'Die Leistung ist gemäß § 4 Nr. 25 UStG von der Umsatzsteuer befreit.', 'requires_note' => false, 'created_at' => $now, 'updated_at' => $now],
+            ['slug' => 'custom', 'name' => 'Sonstiger Grund (Freitext)', 'invoice_text' => null, 'requires_note' => true, 'created_at' => $now, 'updated_at' => $now],
+        ]);
+
+        Schema::table('tenants', function (Blueprint $table) {
+            $table->foreign('tax_exemption_reason')
+                ->references('slug')->on('tax_exemption_reasons')
+                ->restrictOnDelete()->cascadeOnUpdate();
+        });
+
+        Schema::table('events', function (Blueprint $table) {
+            $table->foreign('tax_exemption_reason')
+                ->references('slug')->on('tax_exemption_reasons')
+                ->restrictOnDelete()->cascadeOnUpdate();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('tenants', function (Blueprint $table) {
+            $table->dropForeign(['tax_exemption_reason']);
+        });
+
+        Schema::table('events', function (Blueprint $table) {
+            $table->dropForeign(['tax_exemption_reason']);
+        });
+    }
+};
diff --git a/tests/Feature/EventVatPricingTest.php b/tests/Feature/EventVatPricingTest.php
new file mode 100644
index 0000000..6d96586
--- /dev/null
+++ b/tests/Feature/EventVatPricingTest.php
@@ -0,0 +1,155 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Domains\Event\Actions\CreateEvent\CreateEventCommand;
+use App\Domains\Event\Actions\CreateEvent\CreateEventRequest;
+use App\Enumerations\EatingHabit;
+use App\Enumerations\ParticipationFeeType;
+use App\Models\Event;
+use App\Models\Tenant;
+use App\RelationModels\EventParticipationFee;
+use App\Resources\EventResource;
+use DateTime;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\DB;
+use Tests\TestCase;
+
+class EventVatPricingTest extends TestCase
+{
+    use RefreshDatabase;
+
+    private Tenant $tenant;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->tenant = Tenant::create([
+            'slug' => 'tv',
+            'name' => 'Test',
+            'email' => 't@example.com',
+            'email_finance' => 'finance@example.com',
+            'url' => 'test.local',
+            'account_name' => 'Test e.V.',
+            'account_iban' => 'DE00',
+            'account_bic' => 'XY',
+            'city' => 'Stadt',
+            'postcode' => '00000',
+            'is_active_local_group' => true,
+            'has_active_instance' => true,
+        ]);
+
+        app()->instance('tenant', $this->tenant);
+
+        DB::table('participation_types')->insert(['slug' => 'participant', 'name' => 'Teilnehmer']);
+        DB::table('participation_fee_types')->insert(['slug' => 'fixed', 'name' => 'Fix']);
+        EatingHabit::create(['slug' => EatingHabit::EATING_HABIT_VEGAN, 'name' => 'Vegan']);
+        EatingHabit::create(['slug' => EatingHabit::EATING_HABIT_VEGETARIAN, 'name' => 'Vegetarisch']);
+    }
+
+    private function makeFee(float $amountStandard): EventParticipationFee
+    {
+        return EventParticipationFee::create([
+            'tenant' => $this->tenant->slug,
+            'type' => 'participant',
+            'name' => 'Standard',
+            'description' => null,
+            'amount_standard' => $amountStandard,
+            'amount_reduced' => null,
+            'amount_solidarity' => null,
+        ]);
+    }
+
+    private function makeEvent(bool $taxLiable, int $vatRate, string $mode, int $feeId): Event
+    {
+        return Event::create([
+            'tenant' => $this->tenant->slug,
+            'name' => 'Event',
+            'identifier' => 'evt-' . uniqid(),
+            'location' => 'Ort',
+            'postal_code' => '00000',
+            'email' => 'e@example.com',
+            'start_date' => '2026-09-01',
+            'end_date' => '2026-09-05',
+            'early_bird_end' => '2026-08-20',
+            'registration_final_end' => '2026-08-25',
+            'early_bird_end_amount_increase' => 0,
+            'account_owner' => 'Owner',
+            'account_iban' => 'DE00',
+            'participation_fee_type' => 'fixed',
+            'participation_fee_1' => $feeId,
+            'pay_per_day' => false,
+            'pay_direct' => false,
+            'tax_liable' => $taxLiable,
+            'vat_rate' => $vatRate,
+            'vat_pricing_mode' => $mode,
+        ]);
+    }
+
+    private function calculate(Event $event): float
+    {
+        return new EventResource($event)->calculateAmount(
+            'participant',
+            'standard',
+            new DateTime('2026-09-01'),
+            new DateTime('2026-09-01'),
+            false,
+        )->getAmount();
+    }
+
+    public function test_add_on_mode_adds_vat_on_top(): void
+    {
+        $event = $this->makeEvent(taxLiable: true, vatRate: 19, mode: 'add_on', feeId: $this->makeFee(100.0)->id);
+
+        $this->assertEqualsWithDelta(119.0, $this->calculate($event), 0.001);
+    }
+
+    public function test_inclusive_mode_keeps_amount(): void
+    {
+        $event = $this->makeEvent(taxLiable: true, vatRate: 19, mode: 'inclusive', feeId: $this->makeFee(100.0)->id);
+
+        $this->assertEqualsWithDelta(100.0, $this->calculate($event), 0.001);
+    }
+
+    public function test_not_liable_ignores_add_on_mode(): void
+    {
+        $event = $this->makeEvent(taxLiable: false, vatRate: 19, mode: 'add_on', feeId: $this->makeFee(100.0)->id);
+
+        $this->assertEqualsWithDelta(100.0, $this->calculate($event), 0.001);
+    }
+
+    public function test_create_event_snapshots_tenant_tax_config(): void
+    {
+        $this->tenant->update([
+            'tax_liable' => true,
+            'vat_rate' => 7,
+            'vat_pricing_mode' => 'add_on',
+            'tax_exemption_reason' => null,
+            'tax_exemption_note' => null,
+        ]);
+
+        $response = new CreateEventCommand(new CreateEventRequest(
+            name: 'Sommerlager',
+            location: 'Ort',
+            postalCode: '00000',
+            email: 'e@example.com',
+            begin: new DateTime('2026-09-01'),
+            end: new DateTime('2026-09-05'),
+            earlyBirdEnd: new DateTime('2026-08-20'),
+            registrationFinalEnd: new DateTime('2026-08-25'),
+            earlyBirdEndAmountIncrease: 0,
+            participationFeeType: ParticipationFeeType::where('slug', 'fixed')->first(),
+            accountOwner: 'Owner',
+            accountIban: 'DE00',
+            payPerDay: false,
+        ))->execute();
+
+        $this->assertTrue($response->success);
+
+        $event = $response->event->fresh();
+        $this->assertTrue($event->tax_liable);
+        $this->assertSame(7, $event->vat_rate);
+        $this->assertSame('add_on', $event->vat_pricing_mode);
+    }
+}