diff --git a/spec/fixtures/api/customer.json b/spec/fixtures/api/customer.json
index c851ba4..e6d237a 100644
--- a/spec/fixtures/api/customer.json
+++ b/spec/fixtures/api/customer.json
@@ -21,6 +21,7 @@
     "currency": "EUR",
     "timezone": "Europe/Paris",
     "applicable_timezone": "Europe/Paris",
+    "finalize_zero_amount_invoice": "inherit",
     "billing_configuration": {
       "invoice_grace_period": 3,
       "payment_provider": "stripe",
diff --git a/spec/fixtures/api/organization.json b/spec/fixtures/api/organization.json
index 277ff64..3eb7b88 100644
--- a/spec/fixtures/api/organization.json
+++ b/spec/fixtures/api/organization.json
@@ -21,6 +21,7 @@
     "timezone": "America/New_York",
     "document_numbering": "per_customer",
     "document_number_prefix": "ORG-1234",
+    "finalize_zero_amount_invoice": true,
     "billing_configuration": {
       "invoice_footer": null,
       "invoice_grace_period": 3,