diff --git a/nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-cluster/src/main/java/org/apache/nifi/cluster/coordination/http/endpoints/ParameterContextMerger.java b/nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-cluster/src/main/java/org/apache/nifi/cluster/coordination/http/endpoints/ParameterContextMerger.java
index 7278b54289..805aff7720 100644
--- a/nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-cluster/src/main/java/org/apache/nifi/cluster/coordination/http/endpoints/ParameterContextMerger.java
+++ b/nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-cluster/src/main/java/org/apache/nifi/cluster/coordination/http/endpoints/ParameterContextMerger.java
@@ -142,7 +142,7 @@ public class ParameterContextMerger {
 
         final AffectedComponentDTO mergedComponent = merged.getComponent();
         final AffectedComponentDTO additionalComponent = additional.getComponent();
-        mergedComponent.setActiveThreadCount(mergedComponent.getActiveThreadCount() + additionalComponent.getActiveThreadCount());
+        mergedComponent.setActiveThreadCount(add(mergedComponent.getActiveThreadCount(), additionalComponent.getActiveThreadCount()));
 
         if (mergedComponent.getValidationErrors() == null) {
             mergedComponent.setValidationErrors(new ArrayList<>());
@@ -152,4 +152,14 @@ public class ParameterContextMerger {
             mergedComponent.getValidationErrors().addAll(additionalComponent.getValidationErrors());
         }
     }
+
+    private static Integer add(final Integer a, final Integer b) {
+        if (a == null) {
+            return b;
+        }
+        if (b == null) {
+            return a;
+        }
+        return a + b;
+    }
 }