diff --git a/src/pretix/base/models/event.py b/src/pretix/base/models/event.py
index 9a42ffaa9a..22981b0ef6 100644
--- a/src/pretix/base/models/event.py
+++ b/src/pretix/base/models/event.py
@@ -369,6 +369,7 @@ class Event(EventMixin, LoggedModel):
         This way, we can use this to introduce new default settings to pretix that do not affect existing events.
         """
         self.settings.invoice_renderer = 'modern1'
+        self.settings.invoice_include_expire_date = True
 
     @property
     def social_image(self):
diff --git a/src/pretix/base/services/invoices.py b/src/pretix/base/services/invoices.py
index 662d7f1943..3ca827d388 100644
--- a/src/pretix/base/services/invoices.py
+++ b/src/pretix/base/services/invoices.py
@@ -13,6 +13,7 @@ from django.db import transaction
 from django.db.models import Count
 from django.dispatch import receiver
 from django.utils import timezone
+from django.utils.formats import date_format
 from django.utils.timezone import now
 from django.utils.translation import pgettext, ugettext as _
 from django_countries.fields import Country
@@ -52,11 +53,17 @@ def build_invoice(invoice: Invoice) -> Invoice:
         footer = invoice.event.settings.get('invoice_footer_text', as_type=LazyI18nString)
         if lp and lp.payment_provider:
             if 'payment' in inspect.signature(lp.payment_provider.render_invoice_text).parameters:
-                payment = lp.payment_provider.render_invoice_text(invoice.order, lp)
+                payment = str(lp.payment_provider.render_invoice_text(invoice.order, lp))
             else:
-                payment = lp.payment_provider.render_invoice_text(invoice.order)
+                payment = str(lp.payment_provider.render_invoice_text(invoice.order))
         else:
             payment = ""
+        if invoice.event.settings.invoice_include_expire_date and invoice.order.status == Order.STATUS_PENDING:
+            if payment:
+                payment += "<br />"
+            payment += pgettext("invoice", "Please complete your payment before {expire_date}.").format(
+                expire_date=date_format(invoice.order.expires, "SHORT_DATE_FORMAT")
+            )
 
         invoice.introductory_text = str(introductory).replace('\n', '<br />')
         invoice.additional_text = str(additional).replace('\n', '<br />')
diff --git a/src/pretix/base/settings.py b/src/pretix/base/settings.py
index 2786c2b93f..c87cf874d0 100644
--- a/src/pretix/base/settings.py
+++ b/src/pretix/base/settings.py
@@ -85,6 +85,10 @@ DEFAULTS = {
         'default': 'True',
         'type': bool,
     },
+    'invoice_include_expire_date': {
+        'default': 'False',
+        'type': bool,
+    },
     'invoice_numbers_consecutive': {
         'default': 'True',
         'type': bool,
diff --git a/src/pretix/control/forms/event.py b/src/pretix/control/forms/event.py
index b2c6a4e4f9..a475e080eb 100644
--- a/src/pretix/control/forms/event.py
+++ b/src/pretix/control/forms/event.py
@@ -870,6 +870,11 @@ class InvoiceSettingsForm(SettingsForm):
         label=_("Show attendee names on invoices"),
         required=False
     )
+    invoice_include_expire_date = forms.BooleanField(
+        label=_("Show expiration date of order"),
+        help_text=_("The expiration date will not be shown if the invoice is generated after the order is paid."),
+        required=False
+    )
     invoice_email_attachment = forms.BooleanField(
         label=_("Attach invoices to emails"),
         help_text=_("If invoices are automatically generated for all orders, they will be attached to the order "
diff --git a/src/pretix/control/templates/pretixcontrol/event/invoicing.html b/src/pretix/control/templates/pretixcontrol/event/invoicing.html
index 2c4cbb7198..a36b60eeb5 100644
--- a/src/pretix/control/templates/pretixcontrol/event/invoicing.html
+++ b/src/pretix/control/templates/pretixcontrol/event/invoicing.html
@@ -42,6 +42,7 @@
                 <legend>{% trans "Invoice customization" %}</legend>
                 {% bootstrap_field form.invoice_renderer layout="control" %}
                 {% bootstrap_field form.invoice_attendee_name layout="control" %}
+                {% bootstrap_field form.invoice_include_expire_date layout="control" %}
                 {% bootstrap_field form.invoice_introductory_text layout="control" %}
                 {% bootstrap_field form.invoice_additional_text layout="control" %}
                 {% bootstrap_field form.invoice_footer_text layout="control" %}