diff --git a/lib/org/openpsa/invoices/config/schemadb_send_mail.php b/lib/org/openpsa/invoices/config/schemadb_send_mail.php
index 1df7829be..b8eec9b71 100644
--- a/lib/org/openpsa/invoices/config/schemadb_send_mail.php
+++ b/lib/org/openpsa/invoices/config/schemadb_send_mail.php
@@ -25,6 +25,16 @@
                 'widget' => 'textarea',
                 'required' => true,
             ],
+            'attachments' => [
+                'title' => 'attachments',
+                'storage' => 'attachments',
+                'type' => 'select',
+                'type_config' => [
+                    'options' => [],
+                    'allow_multiple' => true,
+                ],
+                'widget' => 'radiocheckselect',
+            ],
         ],
     ],
 ];
\ No newline at end of file
diff --git a/lib/org/openpsa/invoices/handler/invoice/action.php b/lib/org/openpsa/invoices/handler/invoice/action.php
index ddce819c5..a0fa1ede3 100644
--- a/lib/org/openpsa/invoices/handler/invoice/action.php
+++ b/lib/org/openpsa/invoices/handler/invoice/action.php
@@ -12,6 +12,7 @@
 use Symfony\Component\HttpFoundation\Request;
 use midcom\datamanager\controller;
 use midcom\datamanager\datamanager;
+use midcom\datamanager\storage\blobs;
 
 /**
  * Invoice action handler
@@ -176,6 +177,16 @@ private function get_email_type_config() : array
     private function load_send_mail_controller(array $config) : controller
     {
         $schemadb = schemadb::from_path($this->_config->get('schemadb_send_mail'));
+
+        $pdf_helper = new org_openpsa_invoices_invoice_pdf($this->invoice);
+        $invoice_pdf = $pdf_helper->get_attachment(true);
+
+        $attachment_options = [$invoice_pdf->guid => $invoice_pdf->name];
+        foreach (blobs::get_attachments($this->invoice, 'files') as $attachment) {
+            $attachment_options[$attachment->guid] = $attachment->name;
+        }
+        $schemadb->get('default')->get_field('attachments')['type_config']['options'] = $attachment_options;
+
         $dm = new datamanager($schemadb);
         $billing_data = $this->invoice->get_billing_data(true);
         $to_email = $billing_data->email ?: $this->mail_recipient->email;
@@ -183,7 +194,8 @@ private function load_send_mail_controller(array $config) : controller
         $dm->set_defaults([
             'to_email'=> $to_email,
             'subject' => $config['subject'],
-            'message' => $config['message']
+            'message' => $config['message'],
+            'attachments' => serialize([$invoice_pdf->guid]),
         ]);
 
         return $dm->get_controller();
@@ -233,15 +245,15 @@ public function save_callback(controller $controller)
         }
         $invoice_date = $this->_l10n->get_formatter()->date($this->invoice->date);
 
-        $pdf_helper = new org_openpsa_invoices_invoice_pdf($this->invoice);
-        $attachment = $pdf_helper->get_attachment(true);
-
         $mail = new org_openpsa_mail();
-        $mail->attachments[] = [
-            'name' => $attachment->name,
-            'mimetype' => "application/pdf",
-            'content' => $attachment->read()
-        ];
+        foreach ($data['attachments'] as $attachment_guid) {
+            $attachment = new midcom_db_attachment($attachment_guid);
+            $mail->attachments[] = [
+                'name' => $attachment->name,
+                'mimetype' => $attachment->mimetype,
+                'content' => $attachment->read()
+            ];
+        }
 
         // define replacements for subject / body
         $mail->parameters = [
diff --git a/lib/org/openpsa/invoices/locale/default.de.txt b/lib/org/openpsa/invoices/locale/default.de.txt
index 3fcc5b251..e30058270 100644
--- a/lib/org/openpsa/invoices/locale/default.de.txt
+++ b/lib/org/openpsa/invoices/locale/default.de.txt
@@ -480,6 +480,10 @@ Betreff
 Nachricht
 ---STRINGEND
 
+---STRING attachments
+Anhänge
+---STRINGEND
+
 ---STRING reminder_send_by_mail
 Zahlungserinnerung versenden
 ---STRINGEND
diff --git a/lib/org/openpsa/invoices/locale/default.en.txt b/lib/org/openpsa/invoices/locale/default.en.txt
index f40e3d492..e2ca65894 100644
--- a/lib/org/openpsa/invoices/locale/default.en.txt
+++ b/lib/org/openpsa/invoices/locale/default.en.txt
@@ -468,6 +468,10 @@ Subject
 Message
 ---STRINGEND
 
+---STRING attachments
+Attachments
+---STRINGEND
+
 ---STRING reminder_send_by_mail
 Send payment reminder
 ---STRINGEND
diff --git a/test/org/openpsa/invoices/handler/invoice/actionTest.php b/test/org/openpsa/invoices/handler/invoice/actionTest.php
index 1c1ec53d0..69e2fa250 100644
--- a/test/org/openpsa/invoices/handler/invoice/actionTest.php
+++ b/test/org/openpsa/invoices/handler/invoice/actionTest.php
@@ -14,6 +14,7 @@
 use org_openpsa_invoices_invoice_item_dba;
 use midcom;
 use midcom_db_topic;
+use mock_pdfbuilder;
 
 /**
  * OpenPSA testcase
@@ -143,6 +144,8 @@ public function testHandler_mark_paid()
 
     public function testHandler_send_by_mail()
     {
+        $this->set_config('org.openpsa.invoices', 'invoice_pdfbuilder_class', mock_pdfbuilder::class);
+
         midcom::get()->auth->request_sudo('org.openpsa.invoices');
 
         $invoice = $this->create_object(org_openpsa_invoices_invoice_dba::class, [
@@ -158,6 +161,8 @@ public function testHandler_send_by_mail()
 
     public function testHandler_send_payment_reminder()
     {
+        $this->set_config('org.openpsa.invoices', 'invoice_pdfbuilder_class', mock_pdfbuilder::class);
+
         midcom::get()->auth->request_sudo('org.openpsa.invoices');
 
         $invoice = $this->create_object(org_openpsa_invoices_invoice_dba::class, [
diff --git a/test/utilities/autoload.php b/test/utilities/autoload.php
index 662f8b681..09f41c4ff 100644
--- a/test/utilities/autoload.php
+++ b/test/utilities/autoload.php
@@ -16,3 +16,4 @@
 
 require __DIR__ . '/helpers/sessioning.php';
 require __DIR__ . '/helpers/relocate.php';
+require __DIR__ . '/helpers/pdfbuilder.php';
diff --git a/test/utilities/helpers/pdfbuilder.php b/test/utilities/helpers/pdfbuilder.php
new file mode 100644
index 000000000..429132766
--- /dev/null
+++ b/test/utilities/helpers/pdfbuilder.php
@@ -0,0 +1,24 @@
+<?php
+/**
+ * @package openpsa.test
+ * @author CONTENT CONTROL http://www.contentcontrol-berlin.de/
+ * @copyright CONTENT CONTROL http://www.contentcontrol-berlin.de/
+ * @license http://www.gnu.org/licenses/gpl.html GNU General Public License
+ */
+
+/**
+ * Dummy invoice PDF builder for test runs
+ *
+ * @package openpsa.test
+ */
+class mock_pdfbuilder implements org_openpsa_invoices_interfaces_pdfbuilder
+{
+    public function __construct(org_openpsa_invoices_invoice_dba $invoice)
+    {
+    }
+
+    public function render(string $output_filename)
+    {
+        file_put_contents($output_filename, '%PDF-1.4');
+    }
+}