diff --git a/app/Ninja/Transformers/InvoiceTransformer.php b/app/Ninja/Transformers/InvoiceTransformer.php
index 432e65a2876e..d673c87e95f9 100644
--- a/app/Ninja/Transformers/InvoiceTransformer.php
+++ b/app/Ninja/Transformers/InvoiceTransformer.php
@@ -88,6 +88,7 @@ class InvoiceTransformer extends EntityTransformer
             'custom_taxes1' => (bool) $invoice->custom_taxes1,
             'custom_taxes2' => (bool) $invoice->custom_taxes2,
             'has_expenses' => (bool) $invoice->has_expenses,
+            'quote_invoice_id' => (int) $invoice->quote_invoice_id,
         ];
     }
 }