diff --git a/src/pretix/base/migrations/0311_fix_unshredded_invoices.py b/src/pretix/base/migrations/0311_fix_unshredded_invoices.py
new file mode 100644
index 0000000000..818166df53
--- /dev/null
+++ b/src/pretix/base/migrations/0311_fix_unshredded_invoices.py
@@ -0,0 +1,49 @@
+# Generated by Django 5.2.17 on 2026-09-21 11:30
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+def fix_unshredded_invoices(apps, _):
+    Invoice = apps.get_model("pretixbase", "Invoice")
+    InvoiceLine = apps.get_model("pretixbase", "InvoiceLine")
+    ignore_fields = (
+        # bool/int fields are not listed and skipped automatically
+        'prefix', 'invoice_no', 'full_invoice_no', 'invoice_from', 'invoice_from_name', 'invoice_from_zipcode',
+        'invoice_from_city', 'invoice_from_state', 'invoice_from_country', 'invoice_from_tax_id',
+        'invoice_from_vat_id', 'locale', 'payment_provider_stamp', 'footer_text', 'foreign_currency_display',
+        'foreign_currency_source', 'transmission_type', 'transmission_provider', 'transmission_status',
+    )
+
+    for i in Invoice.objects.filter(shredded=True):
+        for f in Invoice._meta.fields:
+            if f.name in ignore_fields:
+                continue
+            val = getattr(i, f.name, None)
+            if val and isinstance(val, str):
+                setattr(i, f.name, "█")
+            elif val and isinstance(val, list):  # jsonfield
+                setattr(i, f.name, [])
+            elif val and isinstance(val, dict):  # jsonfield
+                setattr(i, f.name, {"_shredded": True})
+        i.save()
+
+    InvoiceLine.objects.filter(
+        attendee_name__isnull=False,
+        invoice__shredded=True
+    ).update(attendee_name="█")
+
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("pretixbase", "0310_question_valid_string_length_min"),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            fix_unshredded_invoices,
+            migrations.RunPython.noop,
+        ),
+    ]
diff --git a/src/pretix/base/shredder.py b/src/pretix/base/shredder.py
index bc38e72ab9..90308820b3 100644
--- a/src/pretix/base/shredder.py
+++ b/src/pretix/base/shredder.py
@@ -50,8 +50,8 @@ from pretix.api.serializers.order import (
 from pretix.api.serializers.waitinglist import WaitingListSerializer
 from pretix.base.i18n import LazyLocaleException
 from pretix.base.models import (
-    CachedCombinedTicket, CachedTicket, Event, InvoiceAddress, OrderPayment,
-    OrderPosition, OrderRefund, OutgoingMail, QuestionAnswer,
+    CachedCombinedTicket, CachedTicket, Event, Invoice, InvoiceAddress,
+    OrderPayment, OrderPosition, OrderRefund, OutgoingMail, QuestionAnswer,
 )
 from pretix.base.services.invoices import invoice_pdf_task
 from pretix.base.signals import register_data_shredders
@@ -598,18 +598,30 @@ class InvoiceShredder(BaseDataShredder):
     def shred_data(self, progress_callback=None):
         qs_i = self.event.invoices.filter(shredded=False)
         total = qs_i.count()
+        ignore_fields = (
+            'prefix', 'invoice_no', 'full_invoice_no', 'invoice_from', 'invoice_from_name', 'invoice_from_zipcode',
+            'invoice_from_city', 'invoice_from_state', 'invoice_from_country', 'invoice_from_tax_id',
+            'invoice_from_vat_id', 'locale', 'payment_provider_stamp', 'footer_text', 'foreign_currency_display',
+            'foreign_currency_source', 'transmission_type', 'transmission_provider', 'transmission_status',
+        )
 
         for i in _progress_helper(qs_i, progress_callback, 0, total):
             if i.file:
                 i.file.delete()
-                i.shredded = True
-                i.introductory_text = "█"
-                i.additional_text = "█"
-                i.invoice_to = "█"
-                i.payment_provider_text = "█"
-                i.transmission_info = {"_shredded": True}
-                i.save()
-                i.lines.update(description="█")
+            i.shredded = True
+
+            for f in Invoice._meta.fields:
+                if f.name in ignore_fields:
+                    continue
+                val = getattr(i, f.name, None)
+                if val and isinstance(val, str):
+                    setattr(i, f.name, "█")
+                elif val and isinstance(val, list):  # jsonfield
+                    setattr(i, f.name, [])
+                elif val and isinstance(val, dict):  # jsonfield
+                    setattr(i, f.name, {"_shredded": True})
+            i.save()
+            i.lines.update(description="█", attendee_name="█")
 
 
 class CachedTicketShredder(BaseDataShredder):
diff --git a/src/tests/base/test_shredders.py b/src/tests/base/test_shredders.py
index d2f0c59c8e..b5633d7e72 100644
--- a/src/tests/base/test_shredders.py
+++ b/src/tests/base/test_shredders.py
@@ -342,8 +342,11 @@ def test_invoice_shredder(event, order):
     s.shred_data()
     inv.refresh_from_db()
 
-    assert "Acme" not in inv.invoice_to
-    assert "icket" not in inv.lines.first().description
+    assert inv.invoice_to == "█"
+    assert inv.invoice_to_company == "█"
+    l = inv.lines.first()
+    assert l.description == "█"
+    assert l.attendee_name == "█"
     assert not inv.file
     assert not os.path.exists(fname)