diff --git a/app/Transformers/CreditInvitationTransformer.php b/app/Transformers/CreditInvitationTransformer.php
index fca841563848..5b230cbb788f 100644
--- a/app/Transformers/CreditInvitationTransformer.php
+++ b/app/Transformers/CreditInvitationTransformer.php
@@ -31,7 +31,7 @@ class CreditInvitationTransformer extends EntityTransformer
             'updated_at'        => (int) $invitation->updated_at,
             'archived_at'       => (int) $invitation->deleted_at,
             'created_at'		=> (int) $invitation->created_at,
-            'email_status'      => $invitation->email_status,
+            'email_status'      => $invitation->email_status ?: '',
             'email_error'       => (string)$invitation->email_error,
         ];
     }
diff --git a/app/Transformers/InvoiceInvitationTransformer.php b/app/Transformers/InvoiceInvitationTransformer.php
index 76a514c409a8..b92084ebdc0c 100644
--- a/app/Transformers/InvoiceInvitationTransformer.php
+++ b/app/Transformers/InvoiceInvitationTransformer.php
@@ -31,7 +31,7 @@ class InvoiceInvitationTransformer extends EntityTransformer
             'updated_at'        => (int) $invitation->updated_at,
             'archived_at'       => (int) $invitation->deleted_at,
             'created_at'        => (int) $invitation->created_at,
-            'email_status'      => $invitation->email_status,
+            'email_status'      => $invitation->email_status ?: '',
             'email_error'       => (string)$invitation->email_error,
         ];
     }
diff --git a/app/Transformers/QuoteInvitationTransformer.php b/app/Transformers/QuoteInvitationTransformer.php
index 021b3b74e380..c6efd4e9ebb4 100644
--- a/app/Transformers/QuoteInvitationTransformer.php
+++ b/app/Transformers/QuoteInvitationTransformer.php
@@ -31,7 +31,7 @@ class QuoteInvitationTransformer extends EntityTransformer
             'updated_at'        => (int) $invitation->updated_at,
             'archived_at'       => (int) $invitation->deleted_at,
             'created_at'       => (int) $invitation->created_at,
-            'email_status'      => $invitation->email_status,
+            'email_status'      => $invitation->email_status ?: '',
             'email_error'       => (string)$invitation->email_error,
         ];
     }