diff --git a/Model/TaxSchemes/NewZealandGst.php b/Model/TaxSchemes/NewZealandGst.php
index ceeb534..19aacac 100644
--- a/Model/TaxSchemes/NewZealandGst.php
+++ b/Model/TaxSchemes/NewZealandGst.php
@@ -380,8 +380,7 @@ public function isValidNzbn(?string $nzbn): bool
         foreach (str_split($withoutcheck) as $key => $digit) {
             $sum += ((int) $digit * $weights[$key]);
         }
-        $remainder = $sum % 10;
-        $calculatedCheck = 10 - $remainder;
+        $calculatedCheck = (ceil($sum/10) * 10) - $sum;
         if ($calculatedCheck == $check) {
             return true;
         }
diff --git a/Test/Unit/CheckNzGstTest.php b/Test/Unit/CheckNzGstTest.php
index 9477b70..f873cb6 100644
--- a/Test/Unit/CheckNzGstTest.php
+++ b/Test/Unit/CheckNzGstTest.php
@@ -71,6 +71,10 @@ public function testIsValidNzbn($number, $valid): void
     public function isValidNZBNDataProvider(): array
     {
         return [
+            ["9429039098740", true],
+            ["9429034243282", true],
+            ["9429041535110", true],
+            ["9429049999198", true],
             ["6291041500213", true],
             ["6291041500212", false],
             ["123456789", false],
@@ -80,3 +84,4 @@ public function isValidNZBNDataProvider(): array
         ];
     }
 }
+