diff --git a/modules/salesforce_mapping/src/SalesforceMappingFieldPluginBase.php b/modules/salesforce_mapping/src/SalesforceMappingFieldPluginBase.php
index 9410f1af19522e08148baf4375a6db686b0555b0..8319f888c2e9ff292abf6077b5bb745c7e4b842c 100644
--- a/modules/salesforce_mapping/src/SalesforceMappingFieldPluginBase.php
+++ b/modules/salesforce_mapping/src/SalesforceMappingFieldPluginBase.php
@@ -285,11 +285,11 @@ abstract class SalesforceMappingFieldPluginBase extends PluginBase implements Sa
         break;
 
       case 'double':
-        $value = (double) $value;
+        $value = $value === NULL ? $value : (double) $value;
         break;
 
       case 'integer':
-        $value = (int) $value;
+        $value = $value === NULL ? $value : (int) $value;
         break;
 
       case 'multipicklist':