diff --git a/db/migrations/2018_12_21_000000_change_users_contact_dect_field_size.php b/db/migrations/2018_12_21_000000_change_users_contact_dect_field_size.php
new file mode 100644
index 00000000..0478b138
--- /dev/null
+++ b/db/migrations/2018_12_21_000000_change_users_contact_dect_field_size.php
@@ -0,0 +1,47 @@
+<?php
+
+namespace Engelsystem\Migrations;
+
+use Engelsystem\Database\Migration\Migration;
+use Illuminate\Database\Schema\Blueprint;
+
+class ChangeUsersContactDectFieldSize extends Migration
+{
+    /** @var array */
+    protected $tables = [
+        'AngelTypes'    => 'contact_dect',
+        'users_contact' => 'dect',
+    ];
+
+    /**
+     * Run the migration
+     */
+    public function up()
+    {
+        $this->changeDectTo(40);
+    }
+
+    /**
+     * Reverse the migration
+     */
+    public function down()
+    {
+        $this->changeDectTo(5);
+    }
+
+    /**
+     * @param int $length
+     */
+    protected function changeDectTo(int $length)
+    {
+        foreach ($this->tables as $table => $column) {
+            if (!$this->schema->hasTable($table)) {
+                continue;
+            }
+
+            $this->schema->table($table, function (Blueprint $table) use ($column, $length) {
+                $table->string($column, $length)->change();
+            });
+        }
+    }
+}
diff --git a/includes/pages/admin_user.php b/includes/pages/admin_user.php
index 63993fc9..4e0fd24b 100644
--- a/includes/pages/admin_user.php
+++ b/includes/pages/admin_user.php
@@ -55,7 +55,7 @@ function admin_user()
         $html .= '  <tr><td>Name</td><td>' . '<input size="40" name="eName" value="' . $user_source->personalData->last_name . '" class="form-control"></td></tr>' . "\n";
         $html .= '  <tr><td>Vorname</td><td>' . '<input size="40" name="eVorname" value="' . $user_source->personalData->first_name . '" class="form-control"></td></tr>' . "\n";
         $html .= '  <tr><td>Handy</td><td>' . '<input type= "tel" size="40" name="eHandy" value="' . $user_source->contact->mobile . '" class="form-control"></td></tr>' . "\n";
-        $html .= '  <tr><td>DECT</td><td>' . '<input size="4" name="eDECT" value="' . $user_source->contact->dect . '" class="form-control"></td></tr>' . "\n";
+        $html .= '  <tr><td>DECT</td><td>' . '<input size="40" name="eDECT" value="' . $user_source->contact->dect . '" class="form-control"></td></tr>' . "\n";
         if ($user_source->settings->email_human) {
             $html .= "  <tr><td>email</td><td>" . '<input type="email" size="40" name="eemail" value="' . $user_source->email . '" class="form-control"></td></tr>' . "\n";
         }
diff --git a/includes/pages/guest_login.php b/includes/pages/guest_login.php
index 2df09d79..1b16333f 100644
--- a/includes/pages/guest_login.php
+++ b/includes/pages/guest_login.php
@@ -168,11 +168,11 @@ function guest_register()
             $preName = strip_request_item('prename');
         }
         if ($request->has('dect')) {
-            if (strlen(strip_request_item('dect')) <= 5) {
+            if (strlen(strip_request_item('dect')) <= 40) {
                 $dect = strip_request_item('dect');
             } else {
                 $valid = false;
-                error(__('For dect numbers are only 5 digits allowed.'));
+                error(__('For dect numbers are only 40 digits allowed.'));
             }
         }
         if ($request->has('mobile')) {
diff --git a/includes/pages/user_settings.php b/includes/pages/user_settings.php
index c39c0ef7..9099f658 100644
--- a/includes/pages/user_settings.php
+++ b/includes/pages/user_settings.php
@@ -72,11 +72,11 @@ function user_settings_main($user_source, $enable_tshirt_size, $tshirt_sizes)
     // Trivia
     $user_source->personalData->last_name = strip_request_item('lastname', $user_source['Name']);
     $user_source->personalData->first_name = strip_request_item('prename', $user_source['Vorname']);
-    if (strlen(strip_request_item('dect')) <= 5) {
+    if (strlen(strip_request_item('dect')) <= 40) {
         $user_source->contact->dect = strip_request_item('dect', $user_source['DECT']);
     } else {
         $valid = false;
-        error(__('For dect numbers are only 5 digits allowed.'));
+        error(__('For dect numbers are only 40 digits allowed.'));
     }
     $user_source->contact->mobile = strip_request_item('mobile', $user_source['Handy']);
 
diff --git a/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.mo b/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.mo
index a1765a6b..7411a1be 100644
Binary files a/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.mo and b/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.mo differ
diff --git a/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.po b/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.po
index 263d1641..3f54c381 100644
--- a/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.po
+++ b/resources/lang/de_DE.UTF-8/LC_MESSAGES/default.po
@@ -1577,8 +1577,8 @@ msgstr ""
 
 #: /Users/msquare/workspace/projects/engelsystem/includes/pages/guest_login.php:190
 #: /Users/msquare/workspace/projects/engelsystem/includes/pages/user_settings.php:85
-msgid "For dect numbers are only 5 digits allowed."
-msgstr "Die DECT Nummer darf nur 5 Zeichen lang sein."
+msgid "For dect numbers are only 40 digits allowed."
+msgstr "Die DECT Nummer darf nur 40 Zeichen lang sein."
 
 #: /Users/msquare/workspace/projects/engelsystem/includes/pages/guest_login.php:274
 msgid "Angel registration successful!"
diff --git a/tests/Unit/Models/User/UserTest.php b/tests/Unit/Models/User/UserTest.php
index c30f7761..9e967892 100644
--- a/tests/Unit/Models/User/UserTest.php
+++ b/tests/Unit/Models/User/UserTest.php
@@ -32,7 +32,7 @@ class UserTest extends TestCase
                 Contact::class,
                 'contact',
                 [
-                    'dect'   => '1234',
+                    'dect'   => '1234567',
                     'email'  => 'foo@bar.batz',
                     'mobile' => '1234/12341234',
                 ]