diff --git a/src/pretix/base/services/tax.py b/src/pretix/base/services/tax.py
index 07255bfa08..287632d111 100644
--- a/src/pretix/base/services/tax.py
+++ b/src/pretix/base/services/tax.py
@@ -94,6 +94,10 @@ def _validate_vat_id_NO(vat_id, country_code):
 def _validate_vat_id_EU(vat_id, country_code):
     # Inspired by vat_moss library
     vat_id = vat_moss.id.normalize(vat_id)
+
+    if not vat_id or len(vat_id) < 3:
+        raise VATIDFinalError(error_messages['invalid'])
+
     number = vat_id[2:]
 
     if vat_id[:2] != cc_to_vat_prefix(country_code):
diff --git a/src/tests/base/test_vat_id_validation.py b/src/tests/base/test_vat_id_validation.py
index de65b87fe6..cd5386ee50 100644
--- a/src/tests/base/test_vat_id_validation.py
+++ b/src/tests/base/test_vat_id_validation.py
@@ -16,6 +16,12 @@ def test_eu_invalid_format():
         validate_vat_id('AT12345', 'AT')
 
 
+@responses.activate
+def test_eu_no_prefix():
+    with pytest.raises(VATIDFinalError):
+        validate_vat_id('12345', 'AT')
+
+
 @responses.activate
 def test_eu_country_mismatch():
     with pytest.raises(VATIDFinalError):