diff --git a/app/Console/Kernel.php b/app/Console/Kernel.php
index 5a5f2227..55cf932c 100644
--- a/app/Console/Kernel.php
+++ b/app/Console/Kernel.php
@@ -4,7 +4,7 @@ namespace App\Console;
 
 use App\Initialize\Actions\InitializeAction;
 use App\Initialize\InitializeMembers;
-use App\Letter\Actions\LetterSendAction;
+use App\Invoice\Actions\InvoiceSendAction;
 use Illuminate\Console\Scheduling\Schedule;
 use Illuminate\Foundation\Console\Kernel as ConsoleKernel;
 use Laravel\Telescope\Console\PruneCommand;
@@ -17,7 +17,7 @@ class Kernel extends ConsoleKernel
      * @var array<int, class-string>
      */
     protected $commands = [
-        LetterSendAction::class,
+        InvoiceSendAction::class,
         InitializeAction::class,
         InitializeMembers::class,
     ];
diff --git a/app/Invoice/Actions/InvoiceSendAction.php b/app/Invoice/Actions/InvoiceSendAction.php
new file mode 100644
index 00000000..8b7a1d0b
--- /dev/null
+++ b/app/Invoice/Actions/InvoiceSendAction.php
@@ -0,0 +1,48 @@
+<?php
+
+namespace App\Invoice\Actions;
+
+use App\Invoice\BillKind;
+use App\Invoice\DocumentFactory;
+use App\Invoice\Queries\BillKindQuery;
+use App\Payment\PaymentMail;
+use Illuminate\Support\Facades\Mail;
+use Illuminate\Support\Facades\Storage;
+use Lorisleiva\Actions\Concerns\AsAction;
+use Zoomyboy\Tex\Tex;
+
+class InvoiceSendAction
+{
+    use AsAction;
+
+    /**
+     * The name and signature of the console command.
+     */
+    public string $commandSignature = 'invoice:send';
+
+    /**
+     * The console command description.
+     *
+     * @var string
+     */
+    protected $description = 'Sends Bills';
+
+    /**
+     * Execute the console command.
+     */
+    public function handle(): int
+    {
+        foreach (app(DocumentFactory::class)->getTypes() as $type) {
+            $invoices = app(DocumentFactory::class)->invoiceCollection($type, new BillKindQuery(BillKind::EMAIL));
+
+            foreach ($invoices as $invoice) {
+                $invoicePath = Storage::disk('temp')->path(Tex::compile($invoice)->storeIn('', 'temp'));
+                Mail::to($invoice->getRecipient())
+                    ->send(new PaymentMail($invoice, $invoicePath));
+                app(DocumentFactory::class)->afterSingle($invoice);
+            }
+        }
+
+        return 0;
+    }
+}
diff --git a/app/Letter/BillDocument.php b/app/Invoice/BillDocument.php
similarity index 95%
rename from app/Letter/BillDocument.php
rename to app/Invoice/BillDocument.php
index f8d6a160..707a1ac0 100644
--- a/app/Letter/BillDocument.php
+++ b/app/Invoice/BillDocument.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 use App\Payment\Payment;
 use Illuminate\Database\Eloquent\Relations\HasMany;
 
-class BillDocument extends Letter
+class BillDocument extends Invoice
 {
     public function linkLabel(): string
     {
diff --git a/app/Letter/BillKind.php b/app/Invoice/BillKind.php
similarity index 96%
rename from app/Letter/BillKind.php
rename to app/Invoice/BillKind.php
index 86bc4bb2..29e9d053 100644
--- a/app/Letter/BillKind.php
+++ b/app/Invoice/BillKind.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 enum BillKind: string
 {
diff --git a/app/Letter/DocumentFactory.php b/app/Invoice/DocumentFactory.php
similarity index 51%
rename from app/Letter/DocumentFactory.php
rename to app/Invoice/DocumentFactory.php
index d376d0a9..e643d5ba 100644
--- a/app/Letter/DocumentFactory.php
+++ b/app/Invoice/DocumentFactory.php
@@ -1,14 +1,14 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
-use App\Letter\Queries\LetterMemberQuery;
+use App\Invoice\Queries\InvoiceMemberQuery;
 use Illuminate\Support\Collection;
 
 class DocumentFactory
 {
     /**
-     * @var array<int, class-string<Letter>>
+     * @var array<int, class-string<Invoice>>
      */
     private array $types = [
         BillDocument::class,
@@ -16,7 +16,7 @@ class DocumentFactory
     ];
 
     /**
-     * @return Collection<int, class-string<Letter>>
+     * @return Collection<int, class-string<Invoice>>
      */
     public function getTypes(): Collection
     {
@@ -24,9 +24,9 @@ class DocumentFactory
     }
 
     /**
-     * @param class-string<Letter> $type
+     * @param class-string<Invoice> $type
      */
-    public function singleLetter(string $type, LetterMemberQuery $query): ?Letter
+    public function singleInvoice(string $type, InvoiceMemberQuery $query): ?Invoice
     {
         $pages = $query->getPages($type);
 
@@ -38,29 +38,29 @@ class DocumentFactory
     }
 
     /**
-     * @param class-string<Letter> $type
+     * @param class-string<Invoice> $type
      *
-     * @return Collection<int, Letter>
+     * @return Collection<int, Invoice>
      */
-    public function letterCollection(string $type, LetterMemberQuery $query): Collection
+    public function invoiceCollection(string $type, InvoiceMemberQuery $query): Collection
     {
         return $query
             ->getPages($type)
             ->map(fn ($page) => $this->resolve($type, collect([$page])));
     }
 
-    public function afterSingle(Letter $letter): void
+    public function afterSingle(Invoice $invoice): void
     {
-        foreach ($letter->allPayments() as $payment) {
-            $letter->afterSingle($payment);
+        foreach ($invoice->allPayments() as $payment) {
+            $invoice->afterSingle($payment);
         }
     }
 
     /**
-     * @param class-string<Letter>  $type
+     * @param class-string<Invoice> $type
      * @param Collection<int, Page> $pages
      */
-    private function resolve(string $type, Collection $pages): Letter
+    private function resolve(string $type, Collection $pages): Invoice
     {
         return new $type($pages);
     }
diff --git a/app/Letter/Letter.php b/app/Invoice/Invoice.php
similarity index 94%
rename from app/Letter/Letter.php
rename to app/Invoice/Invoice.php
index e0a17597..ec508367 100644
--- a/app/Letter/Letter.php
+++ b/app/Invoice/Invoice.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 use App\Payment\Payment;
 use Carbon\Carbon;
@@ -13,7 +13,7 @@ use Zoomyboy\Tex\Document;
 use Zoomyboy\Tex\Engine;
 use Zoomyboy\Tex\Template;
 
-abstract class Letter extends Document
+abstract class Invoice extends Document
 {
     abstract public function getSubject(): string;
 
@@ -44,7 +44,7 @@ abstract class Letter extends Document
     public string $subject;
     protected string $filename;
     public string $until;
-    public LetterSettings $settings;
+    public InvoiceSettings $settings;
 
     /**
      * @param Collection<int, Page> $pages
@@ -55,7 +55,7 @@ abstract class Letter extends Document
         $this->subject = $this->getSubject();
         $this->until = now()->addWeeks(2)->format('d.m.Y');
         $this->setFilename(Str::slug("{$this->getSubject()} für {$pages->first()?->familyName}"));
-        $this->settings = app(LetterSettings::class);
+        $this->settings = app(InvoiceSettings::class);
     }
 
     public function number(int $number): string
diff --git a/app/Letter/LetterSettings.php b/app/Invoice/InvoiceSettings.php
similarity index 91%
rename from app/Letter/LetterSettings.php
rename to app/Invoice/InvoiceSettings.php
index 6ba55fec..c61cbbea 100644
--- a/app/Letter/LetterSettings.php
+++ b/app/Invoice/InvoiceSettings.php
@@ -1,10 +1,10 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 use App\Setting\LocalSettings;
 
-class LetterSettings extends LocalSettings
+class InvoiceSettings extends LocalSettings
 {
     public string $from_long;
 
diff --git a/app/Letter/MailRecipient.php b/app/Invoice/MailRecipient.php
similarity index 90%
rename from app/Letter/MailRecipient.php
rename to app/Invoice/MailRecipient.php
index b59ae145..319572f9 100644
--- a/app/Letter/MailRecipient.php
+++ b/app/Invoice/MailRecipient.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 class MailRecipient
 {
diff --git a/app/Letter/Page.php b/app/Invoice/Page.php
similarity index 98%
rename from app/Letter/Page.php
rename to app/Invoice/Page.php
index 63811564..33760950 100644
--- a/app/Letter/Page.php
+++ b/app/Invoice/Page.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 use App\Member\Member;
 use App\Payment\Payment;
diff --git a/app/Letter/Queries/BillKindQuery.php b/app/Invoice/Queries/BillKindQuery.php
similarity index 75%
rename from app/Letter/Queries/BillKindQuery.php
rename to app/Invoice/Queries/BillKindQuery.php
index 0727c214..e3f48f74 100644
--- a/app/Letter/Queries/BillKindQuery.php
+++ b/app/Invoice/Queries/BillKindQuery.php
@@ -1,12 +1,12 @@
 <?php
 
-namespace App\Letter\Queries;
+namespace App\Invoice\Queries;
 
-use App\Letter\BillKind;
+use App\Invoice\BillKind;
 use App\Member\Member;
 use Illuminate\Database\Eloquent\Builder;
 
-class BillKindQuery extends LetterMemberQuery
+class BillKindQuery extends InvoiceMemberQuery
 {
     public function __construct(
         private BillKind $billKind
diff --git a/app/Letter/Queries/LetterMemberQuery.php b/app/Invoice/Queries/InvoiceMemberQuery.php
similarity index 84%
rename from app/Letter/Queries/LetterMemberQuery.php
rename to app/Invoice/Queries/InvoiceMemberQuery.php
index 3fdc6f41..dc8ba9b3 100644
--- a/app/Letter/Queries/LetterMemberQuery.php
+++ b/app/Invoice/Queries/InvoiceMemberQuery.php
@@ -1,16 +1,16 @@
 <?php
 
-namespace App\Letter\Queries;
+namespace App\Invoice\Queries;
 
-use App\Letter\Letter;
-use App\Letter\Page;
+use App\Invoice\Invoice;
+use App\Invoice\Page;
 use App\Member\Member;
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Collection as EloquentCollection;
 use Illuminate\Support\Collection;
 use Illuminate\Support\Str;
 
-abstract class LetterMemberQuery
+abstract class InvoiceMemberQuery
 {
     /**
      * @return Builder<Member>
@@ -18,7 +18,7 @@ abstract class LetterMemberQuery
     abstract protected function getQuery(): Builder;
 
     /**
-     * @param class-string<Letter> $type
+     * @param class-string<Invoice> $type
      *
      * @return Collection<int, Page>
      */
@@ -32,7 +32,7 @@ abstract class LetterMemberQuery
     }
 
     /**
-     * @param class-string<Letter> $type
+     * @param class-string<Invoice> $type
      *
      * @return EloquentCollection<int, Member>
      */
diff --git a/app/Letter/Queries/SingleMemberQuery.php b/app/Invoice/Queries/SingleMemberQuery.php
similarity index 81%
rename from app/Letter/Queries/SingleMemberQuery.php
rename to app/Invoice/Queries/SingleMemberQuery.php
index 8e5d6520..882108f3 100644
--- a/app/Letter/Queries/SingleMemberQuery.php
+++ b/app/Invoice/Queries/SingleMemberQuery.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace App\Letter\Queries;
+namespace App\Invoice\Queries;
 
 use App\Member\Member;
 use Illuminate\Database\Eloquent\Builder;
 
-class SingleMemberQuery extends LetterMemberQuery
+class SingleMemberQuery extends InvoiceMemberQuery
 {
     public function __construct(
         private Member $member
diff --git a/app/Letter/RememberDocument.php b/app/Invoice/RememberDocument.php
similarity index 95%
rename from app/Letter/RememberDocument.php
rename to app/Invoice/RememberDocument.php
index 1a08c61a..12e0b2ee 100644
--- a/app/Letter/RememberDocument.php
+++ b/app/Invoice/RememberDocument.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 use App\Payment\Payment;
 use Illuminate\Database\Eloquent\Relations\HasMany;
 
-class RememberDocument extends Letter
+class RememberDocument extends Invoice
 {
     public function linkLabel(): string
     {
diff --git a/app/Letter/SettingIndexAction.php b/app/Invoice/SettingIndexAction.php
similarity index 85%
rename from app/Letter/SettingIndexAction.php
rename to app/Invoice/SettingIndexAction.php
index 6e753635..6a8f13cd 100644
--- a/app/Letter/SettingIndexAction.php
+++ b/app/Invoice/SettingIndexAction.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 use Inertia\Inertia;
 use Inertia\Response;
@@ -13,7 +13,7 @@ class SettingIndexAction
     /**
      * @return array<string, string>
      */
-    public function handle(LetterSettings $settings): array
+    public function handle(InvoiceSettings $settings): array
     {
         return [
             'from_long' => $settings->from_long,
@@ -29,7 +29,7 @@ class SettingIndexAction
         ];
     }
 
-    public function asController(LetterSettings $settings): Response
+    public function asController(InvoiceSettings $settings): Response
     {
         session()->put('menu', 'setting');
         session()->put('title', 'Rechnungs-Einstellungen');
diff --git a/app/Letter/SettingSaveAction.php b/app/Invoice/SettingSaveAction.php
similarity index 93%
rename from app/Letter/SettingSaveAction.php
rename to app/Invoice/SettingSaveAction.php
index 7c6d19a2..37db4931 100644
--- a/app/Letter/SettingSaveAction.php
+++ b/app/Invoice/SettingSaveAction.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace App\Letter;
+namespace App\Invoice;
 
 use Illuminate\Http\RedirectResponse;
 use Lorisleiva\Actions\ActionRequest;
@@ -15,7 +15,7 @@ class SettingSaveAction
      */
     public function handle(array $input): void
     {
-        $settings = app(LetterSettings::class);
+        $settings = app(InvoiceSettings::class);
 
         $settings->fill([
             'from_long' => $input['from_long'] ?? '',
diff --git a/app/Letter/Actions/LetterSendAction.php b/app/Letter/Actions/LetterSendAction.php
deleted file mode 100644
index 312aa1e7..00000000
--- a/app/Letter/Actions/LetterSendAction.php
+++ /dev/null
@@ -1,48 +0,0 @@
-<?php
-
-namespace App\Letter\Actions;
-
-use App\Letter\BillKind;
-use App\Letter\DocumentFactory;
-use App\Letter\Queries\BillKindQuery;
-use App\Payment\PaymentMail;
-use Illuminate\Support\Facades\Mail;
-use Illuminate\Support\Facades\Storage;
-use Lorisleiva\Actions\Concerns\AsAction;
-use Zoomyboy\Tex\Tex;
-
-class LetterSendAction
-{
-    use AsAction;
-
-    /**
-     * The name and signature of the console command.
-     */
-    public string $commandSignature = 'letter:send';
-
-    /**
-     * The console command description.
-     *
-     * @var string
-     */
-    protected $description = 'Sends Bills';
-
-    /**
-     * Execute the console command.
-     */
-    public function handle(): int
-    {
-        foreach (app(DocumentFactory::class)->getTypes() as $type) {
-            $letters = app(DocumentFactory::class)->letterCollection($type, new BillKindQuery(BillKind::EMAIL));
-
-            foreach ($letters as $letter) {
-                $letterPath = Storage::disk('temp')->path(Tex::compile($letter)->storeIn('', 'temp'));
-                Mail::to($letter->getRecipient())
-                    ->send(new PaymentMail($letter, $letterPath));
-                app(DocumentFactory::class)->afterSingle($letter);
-            }
-        }
-
-        return 0;
-    }
-}
diff --git a/app/Member/FilterScope.php b/app/Member/FilterScope.php
index 26bd8172..6ca8ea5f 100644
--- a/app/Member/FilterScope.php
+++ b/app/Member/FilterScope.php
@@ -2,7 +2,7 @@
 
 namespace App\Member;
 
-use App\Letter\BillKind;
+use App\Invoice\BillKind;
 use App\Lib\Filter;
 use Illuminate\Database\Eloquent\Builder;
 use Spatie\LaravelData\Attributes\MapInputName;
diff --git a/app/Member/Member.php b/app/Member/Member.php
index 3a6f22be..212d23e9 100644
--- a/app/Member/Member.php
+++ b/app/Member/Member.php
@@ -7,7 +7,7 @@ use App\Country;
 use App\Course\Models\CourseMember;
 use App\Gender;
 use App\Group;
-use App\Letter\BillKind;
+use App\Invoice\BillKind;
 use App\Nami\HasNamiField;
 use App\Nationality;
 use App\Payment\Payment;
diff --git a/app/Member/MemberController.php b/app/Member/MemberController.php
index 1d4b208e..fdaf36ac 100644
--- a/app/Member/MemberController.php
+++ b/app/Member/MemberController.php
@@ -8,7 +8,7 @@ use App\Country;
 use App\Gender;
 use App\Http\Controllers\Controller;
 use App\Http\Views\MemberView;
-use App\Letter\BillKind;
+use App\Invoice\BillKind;
 use App\Nationality;
 use App\Payment\Subscription;
 use App\Region;
diff --git a/app/Member/MemberRequest.php b/app/Member/MemberRequest.php
index d5515eed..cd273587 100644
--- a/app/Member/MemberRequest.php
+++ b/app/Member/MemberRequest.php
@@ -4,7 +4,7 @@ namespace App\Member;
 
 use App\Activity;
 use App\Group;
-use App\Letter\BillKind;
+use App\Invoice\BillKind;
 use App\Member\Actions\NamiPutMemberAction;
 use App\Setting\NamiSettings;
 use App\Subactivity;
@@ -72,7 +72,7 @@ class MemberRequest extends FormRequest
             'send_newspaper' => 'boolean',
             'main_phone' => ['nullable', new ValidPhoneRule('Telefon (Eltern)')],
             'mobile_phone' => ['nullable', new ValidPhoneRule('Handy (Eltern)')],
-            'letter_address' => '',
+            'invoice_address' => '',
             'gender_id' => 'nullable|exists:genders,id',
             'region_id' => 'nullable|exists:regions,id',
             'nationality_id' => 'required|exists:nationalities,id',
diff --git a/app/Payment/ActionFactory.php b/app/Payment/ActionFactory.php
index 4502b785..cd7716d5 100644
--- a/app/Payment/ActionFactory.php
+++ b/app/Payment/ActionFactory.php
@@ -2,7 +2,7 @@
 
 namespace App\Payment;
 
-use App\Letter\DocumentFactory;
+use App\Invoice\DocumentFactory;
 use Illuminate\Support\Collection;
 
 class ActionFactory
diff --git a/app/Payment/PaymentMail.php b/app/Payment/PaymentMail.php
index 2fad5612..afdd1bcd 100644
--- a/app/Payment/PaymentMail.php
+++ b/app/Payment/PaymentMail.php
@@ -2,7 +2,7 @@
 
 namespace App\Payment;
 
-use App\Letter\Letter;
+use App\Invoice\Invoice;
 use Illuminate\Bus\Queueable;
 use Illuminate\Mail\Mailable;
 use Illuminate\Queue\SerializesModels;
@@ -12,7 +12,7 @@ class PaymentMail extends Mailable
     use Queueable;
     use SerializesModels;
 
-    public Letter $letter;
+    public Invoice $invoice;
     public string $filename;
     public string $salutation;
 
@@ -21,11 +21,11 @@ class PaymentMail extends Mailable
      *
      * @return void
      */
-    public function __construct(Letter $letter, string $filename)
+    public function __construct(Invoice $invoice, string $filename)
     {
-        $this->letter = $letter;
+        $this->invoice = $invoice;
         $this->filename = $filename;
-        $this->salutation = 'Liebe Familie '.$letter->pages->first()->familyName;
+        $this->salutation = 'Liebe Familie '.$invoice->pages->first()->familyName;
     }
 
     /**
@@ -35,9 +35,9 @@ class PaymentMail extends Mailable
      */
     public function build()
     {
-        return $this->markdown($this->letter->mailView())
+        return $this->markdown($this->invoice->mailView())
                     ->attach($this->filename)
                     ->replyTo('kasse@stamm-silva.de')
-                    ->subject($this->letter->getSubject().' | DPSG Stamm Silva');
+                    ->subject($this->invoice->getSubject().' | DPSG Stamm Silva');
     }
 }
diff --git a/app/Payment/SendpaymentController.php b/app/Payment/SendpaymentController.php
index 2c97df47..5036777d 100644
--- a/app/Payment/SendpaymentController.php
+++ b/app/Payment/SendpaymentController.php
@@ -3,9 +3,9 @@
 namespace App\Payment;
 
 use App\Http\Controllers\Controller;
-use App\Letter\BillKind;
-use App\Letter\DocumentFactory;
-use App\Letter\Queries\BillKindQuery;
+use App\Invoice\BillKind;
+use App\Invoice\DocumentFactory;
+use App\Invoice\Queries\BillKindQuery;
 use Illuminate\Contracts\Support\Responsable;
 use Illuminate\Http\Request;
 use Illuminate\Http\Response;
@@ -30,14 +30,14 @@ class SendpaymentController extends Controller
      */
     public function send(Request $request)
     {
-        $letter = app(DocumentFactory::class)->singleLetter($request->type, new BillKindQuery(BillKind::POST));
+        $invoice = app(DocumentFactory::class)->singleInvoice($request->type, new BillKindQuery(BillKind::POST));
 
-        if (is_null($letter)) {
+        if (is_null($invoice)) {
             return response()->noContent();
         }
 
-        $pdfFile = Tex::compile($letter);
-        app(DocumentFactory::class)->afterSingle($letter);
+        $pdfFile = Tex::compile($invoice);
+        app(DocumentFactory::class)->afterSingle($invoice);
 
         return $pdfFile;
     }
diff --git a/app/Pdf/MemberPdfController.php b/app/Pdf/MemberPdfController.php
index dc997a75..d6b85e02 100644
--- a/app/Pdf/MemberPdfController.php
+++ b/app/Pdf/MemberPdfController.php
@@ -3,8 +3,8 @@
 namespace App\Pdf;
 
 use App\Http\Controllers\Controller;
-use App\Letter\DocumentFactory;
-use App\Letter\Queries\SingleMemberQuery;
+use App\Invoice\DocumentFactory;
+use App\Invoice\Queries\SingleMemberQuery;
 use App\Member\Member;
 use Illuminate\Contracts\Support\Responsable;
 use Illuminate\Http\Request;
@@ -18,10 +18,10 @@ class MemberPdfController extends Controller
      */
     public function __invoke(Request $request, Member $member)
     {
-        $letter = app(DocumentFactory::class)->singleLetter($request->type, new SingleMemberQuery($member));
+        $invoice = app(DocumentFactory::class)->singleInvoice($request->type, new SingleMemberQuery($member));
 
-        return null === $letter
+        return null === $invoice
             ? response()->noContent()
-            : Tex::compile($letter);
+            : Tex::compile($invoice);
     }
 }
diff --git a/app/Setting/SettingServiceProvider.php b/app/Setting/SettingServiceProvider.php
index a8e59cf7..24e14ac9 100644
--- a/app/Setting/SettingServiceProvider.php
+++ b/app/Setting/SettingServiceProvider.php
@@ -2,7 +2,7 @@
 
 namespace App\Setting;
 
-use App\Letter\LetterSettings;
+use App\Invoice\InvoiceSettings;
 use App\Mailman\MailmanSettings;
 use Illuminate\Support\ServiceProvider;
 
@@ -25,7 +25,7 @@ class SettingServiceProvider extends ServiceProvider
      */
     public function boot()
     {
-        app(SettingFactory::class)->register(LetterSettings::class);
+        app(SettingFactory::class)->register(InvoiceSettings::class);
         app(SettingFactory::class)->register(MailmanSettings::class);
     }
 }
diff --git a/database/factories/Member/MemberFactory.php b/database/factories/Member/MemberFactory.php
index 93d8ff2a..81c1b860 100644
--- a/database/factories/Member/MemberFactory.php
+++ b/database/factories/Member/MemberFactory.php
@@ -5,7 +5,7 @@ namespace Database\Factories\Member;
 use App\Country;
 use App\Fee;
 use App\Group;
-use App\Letter\BillKind;
+use App\Invoice\BillKind;
 use App\Member\Member;
 use App\Nationality;
 use App\Payment\Payment;
diff --git a/phpstan.neon b/phpstan.neon
index 78807771..8d6a12a3 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -630,7 +630,7 @@ parameters:
             path: app/Contribution/ContributionFactory.php
 
         -
-            message: "#^Return type of call to method Illuminate\\\\Support\\\\Collection\\<int,class\\-string\\<App\\\\Letter\\\\Letter\\>\\>\\:\\:map\\(\\) contains unresolvable type\\.$#"
+            message: "#^Return type of call to method Illuminate\\\\Support\\\\Collection\\<int,class\\-string\\<App\\\\Invoice\\\\Invoice\\>\\>\\:\\:map\\(\\) contains unresolvable type\\.$#"
             count: 1
             path: app/Payment/ActionFactory.php
 
diff --git a/tests/Feature/Bill/SettingTest.php b/tests/Feature/Bill/SettingTest.php
index 7cf32b00..0a491307 100644
--- a/tests/Feature/Bill/SettingTest.php
+++ b/tests/Feature/Bill/SettingTest.php
@@ -2,7 +2,7 @@
 
 namespace Tests\Feature\Bill;
 
-use App\Letter\LetterSettings;
+use App\Invoice\InvoiceSettings;
 use Illuminate\Foundation\Testing\DatabaseTransactions;
 use Tests\TestCase;
 
@@ -13,7 +13,7 @@ class SettingTest extends TestCase
     public function testSettingIndex(): void
     {
         $this->withoutExceptionHandling()->login()->loginNami();
-        LetterSettings::fake([
+        InvoiceSettings::fake([
             'from_long' => 'DPSG Stamm Muster',
             'from' => 'Stamm Muster',
             'mobile' => '+49 176 55555',
@@ -80,7 +80,7 @@ class SettingTest extends TestCase
         ]);
 
         $response->assertRedirect('/setting/bill');
-        $settings = app(LetterSettings::class);
+        $settings = app(InvoiceSettings::class);
         $this->assertEquals('DPSG Stamm Muster', $settings->from_long);
         $this->assertEquals('DE05', $settings->iban);
         $this->assertEquals('SOLSDE', $settings->bic);
diff --git a/tests/Feature/Letter/DocumentFactoryTest.php b/tests/Feature/Invoice/DocumentFactoryTest.php
similarity index 75%
rename from tests/Feature/Letter/DocumentFactoryTest.php
rename to tests/Feature/Invoice/DocumentFactoryTest.php
index 5fcf9825..319c0250 100644
--- a/tests/Feature/Letter/DocumentFactoryTest.php
+++ b/tests/Feature/Invoice/DocumentFactoryTest.php
@@ -1,13 +1,13 @@
 <?php
 
-namespace Tests\Feature\Letter;
+namespace Tests\Feature\Invoice;
 
-use App\Letter\BillDocument;
-use App\Letter\DocumentFactory;
-use App\Letter\LetterSettings;
-use App\Letter\Queries\LetterMemberQuery;
-use App\Letter\Queries\SingleMemberQuery;
-use App\Letter\RememberDocument;
+use App\Invoice\BillDocument;
+use App\Invoice\DocumentFactory;
+use App\Invoice\InvoiceSettings;
+use App\Invoice\Queries\InvoiceMemberQuery;
+use App\Invoice\Queries\SingleMemberQuery;
+use App\Invoice\RememberDocument;
 use App\Member\Member;
 use App\Payment\Payment;
 use Illuminate\Foundation\Testing\DatabaseTransactions;
@@ -20,14 +20,14 @@ class DocumentFactoryTest extends TestCase
     use DatabaseTransactions;
 
     /**
-     * @testWith ["\\App\\Letter\\BillDocument"]
-     *           ["\\App\\Letter\\RememberDocument"]
+     * @testWith ["\\App\\Invoice\\BillDocument"]
+     *           ["\\App\\Invoice\\RememberDocument"]
      */
     public function testItDoesntReturnARepositoryWhenMemberDoesntHavePayments(): void
     {
         $member = Member::factory()->defaults()->create();
-        $letter = app(DocumentFactory::class)->singleLetter(BillDocument::class, $this->query($member));
-        $this->assertNull($letter);
+        $invoice = app(DocumentFactory::class)->singleInvoice(BillDocument::class, $this->query($member));
+        $this->assertNull($invoice);
     }
 
     public function testItDisplaysMemberInformation(): void
@@ -47,9 +47,9 @@ class DocumentFactoryTest extends TestCase
             ]))
             ->create();
 
-        $letter = app(DocumentFactory::class)->singleLetter(BillDocument::class, $this->query($member));
+        $invoice = app(DocumentFactory::class)->singleInvoice(BillDocument::class, $this->query($member));
 
-        $letter->assertHasAllContent([
+        $invoice->assertHasAllContent([
             'Rechnung',
             '15.00',
             '::subName:: 1995 für ::firstname:: ::lastname::',
@@ -72,9 +72,9 @@ class DocumentFactoryTest extends TestCase
             ], ['split' => true]))
             ->create();
 
-        $letter = app(DocumentFactory::class)->singleLetter(BillDocument::class, $this->query($member));
+        $invoice = app(DocumentFactory::class)->singleInvoice(BillDocument::class, $this->query($member));
 
-        $letter->assertHasAllContent([
+        $invoice->assertHasAllContent([
             'Rechnung',
             '10.00',
             '5.00',
@@ -92,9 +92,9 @@ class DocumentFactoryTest extends TestCase
             ->has(Payment::factory()->notPaid()->nr('1995'))
             ->create();
 
-        $letter = app(DocumentFactory::class)->singleLetter(BillDocument::class, $this->query($member));
+        $invoice = app(DocumentFactory::class)->singleInvoice(BillDocument::class, $this->query($member));
 
-        $this->assertEquals('rechnung-fur-lastname.pdf', $letter->compiledFilename());
+        $this->assertEquals('rechnung-fur-lastname.pdf', $invoice->compiledFilename());
     }
 
     public function testRememberSetsFilename(): void
@@ -105,9 +105,9 @@ class DocumentFactoryTest extends TestCase
             ->has(Payment::factory()->notPaid())
             ->create();
 
-        $letter = app(DocumentFactory::class)->singleLetter(RememberDocument::class, $this->query($member));
+        $invoice = app(DocumentFactory::class)->singleInvoice(RememberDocument::class, $this->query($member));
 
-        $this->assertEquals('zahlungserinnerung-fur-lastname.pdf', $letter->compiledFilename());
+        $this->assertEquals('zahlungserinnerung-fur-lastname.pdf', $invoice->compiledFilename());
     }
 
     public function testItCreatesOneFileForFamilyMembers(): void
@@ -123,18 +123,18 @@ class DocumentFactoryTest extends TestCase
             ->has(Payment::factory()->notPaid()->nr('nr2'))
             ->create();
 
-        $letter = app(DocumentFactory::class)->singleLetter(BillDocument::class, $this->query($firstMember));
+        $invoice = app(DocumentFactory::class)->singleInvoice(BillDocument::class, $this->query($firstMember));
 
-        $letter->assertHasAllContent(['Max1', 'Max2', 'nr1', 'nr2']);
+        $invoice->assertHasAllContent(['Max1', 'Max2', 'nr1', 'nr2']);
     }
 
     /**
-     * @testWith ["App\\Letter\\BillDocument"]
-     *           ["App\\Letter\\RememberDocument"]
+     * @testWith ["App\\Invoice\\BillDocument"]
+     *           ["App\\Invoice\\RememberDocument"]
      */
     public function testItDisplaysSettings(string $type): void
     {
-        LetterSettings::fake([
+        InvoiceSettings::fake([
             'from_long' => 'langer Stammesname',
             'from' => 'Stammeskurz',
             'mobile' => '+49 176 55555',
@@ -151,9 +151,9 @@ class DocumentFactoryTest extends TestCase
             ->has(Payment::factory()->notPaid()->nr('nr2'))
             ->create();
 
-        $letter = app(DocumentFactory::class)->singleLetter($type, $this->query($member));
+        $invoice = app(DocumentFactory::class)->singleInvoice($type, $this->query($member));
 
-        $letter->assertHasAllContent([
+        $invoice->assertHasAllContent([
             'langer Stammesname',
             'Stammeskurz',
             '+49 176 55555',
@@ -185,7 +185,7 @@ class DocumentFactoryTest extends TestCase
         $this->assertEquals('inline; filename="rechnung-fur-lastname.pdf"', $response->headers->get('content-disposition'));
     }
 
-    private function query(Member $member): LetterMemberQuery
+    private function query(Member $member): InvoiceMemberQuery
     {
         return new SingleMemberQuery($member);
     }
diff --git a/tests/Feature/Letter/LetterSendActionTest.php b/tests/Feature/Invoice/InvoiceSendActionTest.php
similarity index 87%
rename from tests/Feature/Letter/LetterSendActionTest.php
rename to tests/Feature/Invoice/InvoiceSendActionTest.php
index 3c019f26..b71cb164 100644
--- a/tests/Feature/Letter/LetterSendActionTest.php
+++ b/tests/Feature/Invoice/InvoiceSendActionTest.php
@@ -1,9 +1,9 @@
 <?php
 
-namespace Tests\Feature\Letter;
+namespace Tests\Feature\Invoice;
 
-use App\Letter\Actions\LetterSendAction;
-use App\Letter\BillDocument;
+use App\Invoice\Actions\InvoiceSendAction;
+use App\Invoice\BillDocument;
 use App\Member\Member;
 use App\Payment\Payment;
 use App\Payment\PaymentMail;
@@ -15,7 +15,7 @@ use Tests\RequestFactories\Child;
 use Tests\TestCase;
 use Zoomyboy\Tex\Tex;
 
-class LetterSendActionTest extends TestCase
+class InvoiceSendActionTest extends TestCase
 {
     use DatabaseTransactions;
 
@@ -41,7 +41,7 @@ class LetterSendActionTest extends TestCase
     {
         Mail::fake();
 
-        Artisan::call('letter:send');
+        Artisan::call('invoice:send');
 
         Mail::assertSent(PaymentMail::class, fn ($mail) => Storage::disk('temp')->path('rechnung-fur-mom.pdf') === $mail->filename && Storage::disk('temp')->exists('rechnung-fur-mom.pdf'));
     }
@@ -51,7 +51,7 @@ class LetterSendActionTest extends TestCase
         Mail::fake();
         Tex::spy();
 
-        LetterSendAction::run();
+        InvoiceSendAction::run();
 
         Tex::assertCompiled(BillDocument::class, fn ($document) => 'Mom' === $document->pages->first()->familyName
             && $document->pages->first()->getPositions() === ['tollerbeitrag 1997 für Lah Mom' => '54.00']
diff --git a/tests/Feature/Sendpayment/SendpaymentTest.php b/tests/Feature/Sendpayment/SendpaymentTest.php
index 4453c160..52ae2aef 100644
--- a/tests/Feature/Sendpayment/SendpaymentTest.php
+++ b/tests/Feature/Sendpayment/SendpaymentTest.php
@@ -2,14 +2,14 @@
 
 namespace Tests\Feature\Sendpayment;
 
-use App\Letter\BillDocument;
-use App\Letter\LetterSettings;
+use App\Invoice\BillDocument;
+use App\Invoice\InvoiceSettings;
 use App\Member\Member;
 use App\Payment\Payment;
 use App\Payment\Status;
 use Illuminate\Foundation\Testing\DatabaseTransactions;
 use Tests\RequestFactories\Child;
-use Tests\RequestFactories\LetterSettingsFake;
+use Tests\RequestFactories\InvoiceSettingsFake;
 use Tests\TestCase;
 use Zoomyboy\Tex\Tex;
 
@@ -32,7 +32,7 @@ class SendpaymentTest extends TestCase
 
     public function testItCanCreatePdfPayments(): void
     {
-        LetterSettings::fake(LetterSettingsFake::new()->create());
+        InvoiceSettings::fake(InvoiceSettingsFake::new()->create());
         Tex::spy();
         $this->withoutExceptionHandling();
         $this->login()->loginNami();
@@ -43,7 +43,7 @@ class SendpaymentTest extends TestCase
             ->postBillKind()
             ->create();
 
-        $response = $this->call('GET', route('sendpayment.pdf'), ['type' => 'App\\Letter\\BillDocument']);
+        $response = $this->call('GET', route('sendpayment.pdf'), ['type' => 'App\\Invoice\\BillDocument']);
 
         $response->assertOk();
         $this->assertEquals(Status::firstWhere('name', 'Rechnung gestellt')->id, $member->payments->firstWhere('nr', '1997')->status_id);
@@ -64,7 +64,7 @@ class SendpaymentTest extends TestCase
             ->emailBillKind()
             ->create();
 
-        $response = $this->call('GET', route('sendpayment.pdf'), ['type' => 'App\\Letter\\BillDocument']);
+        $response = $this->call('GET', route('sendpayment.pdf'), ['type' => 'App\\Invoice\\BillDocument']);
 
         $response->assertStatus(204);
         Tex::assertNotCompiled(BillDocument::class);
diff --git a/tests/RequestFactories/LetterSettingsFake.php b/tests/RequestFactories/InvoiceSettingsFake.php
similarity index 91%
rename from tests/RequestFactories/LetterSettingsFake.php
rename to tests/RequestFactories/InvoiceSettingsFake.php
index bc504733..a0ee76fd 100644
--- a/tests/RequestFactories/LetterSettingsFake.php
+++ b/tests/RequestFactories/InvoiceSettingsFake.php
@@ -4,7 +4,7 @@ namespace Tests\RequestFactories;
 
 use Worksome\RequestFactories\RequestFactory;
 
-class LetterSettingsFake extends RequestFactory
+class InvoiceSettingsFake extends RequestFactory
 {
     public function definition(): array
     {