diff --git a/src/Client/Profile/Company.php b/src/Client/Profile/Company.php
index 3e2fa57..da547b7 100644
--- a/src/Client/Profile/Company.php
+++ b/src/Client/Profile/Company.php
@@ -69,7 +69,7 @@ public function getKvkNumber(): int
         return $this->kvkNumber;
     }
 
-    public function getBranchNumber(): string
+    public function getBranchNumber(): ?string
     {
         return $this->branchNumber;
     }