diff --git a/app/DataMapper/Tax/BaseRule.php b/app/DataMapper/Tax/BaseRule.php
index ccc0d46a4449..d921f2006887 100644
--- a/app/DataMapper/Tax/BaseRule.php
+++ b/app/DataMapper/Tax/BaseRule.php
@@ -271,7 +271,7 @@ class BaseRule implements RuleInterface
     public function isTaxableRegion(): bool
     {
         return $this->client->company->tax_data->regions->{$this->client_region}->tax_all_subregions ||
-        (property_exists($this->client->company->tax_data->regions->{$this->client_region}->subregions, $this->client_subregion) && $this->client->company->tax_data->regions->{$this->client_region}->subregions->{$this->client_subregion}->apply_tax);
+        (property_exists($this->client->company->tax_data->regions->{$this->client_region}->subregions, $this->client_subregion) && ($this->client->company->tax_data->regions->{$this->client_region}->subregions->{$this->client_subregion}->apply_tax ?? false));
     }
 
     public function defaultForeign(): self