diff --git a/core/modules/views/src/Plugin/views/filter/FilterPluginBase.php b/core/modules/views/src/Plugin/views/filter/FilterPluginBase.php
index 1d24826b75..4e29fb04a6 100644
--- a/core/modules/views/src/Plugin/views/filter/FilterPluginBase.php
+++ b/core/modules/views/src/Plugin/views/filter/FilterPluginBase.php
@@ -1492,10 +1492,10 @@ public function acceptExposedInput($input) {
 
     if (!empty($this->options['expose']['identifier'])) {
       if ($this->options['is_grouped']) {
-        $value = $input[$this->options['group_info']['identifier']];
+        $value = $input[$this->options['group_info']['identifier']] ?? NULL;
       }
       else {
-        $value = $input[$this->options['expose']['identifier']];
+        $value = $input[$this->options['expose']['identifier']] ?? NULL;
       }
 
       // Various ways to check for the absence of non-required input.