diff --git a/src/main/java/net/openhft/chronicle/map/StatelessChronicleMap.java b/src/main/java/net/openhft/chronicle/map/StatelessChronicleMap.java
index 3b2dfbb66..aa4f654e2 100644
--- a/src/main/java/net/openhft/chronicle/map/StatelessChronicleMap.java
+++ b/src/main/java/net/openhft/chronicle/map/StatelessChronicleMap.java
@@ -350,6 +350,8 @@ class StatelessChronicleMap<K, V> implements ChronicleMap<K, V>, Closeable, Clon
 
 
     public synchronized V putIfAbsent(K key, V value) {
+        if (key == null)
+            throw new NullPointerException();
         final long sizeLocation = writeEventAnSkip(PUT_IF_ABSENT);
         final ThreadLocalCopies local = keyValueSerializer.threadLocalCopies();
         writeKey(key, local);
@@ -532,6 +534,8 @@ class StatelessChronicleMap<K, V> implements ChronicleMap<K, V>, Closeable, Clon
 
 
     public synchronized V put(K key, V value) {
+        if (key == null)
+            throw new NullPointerException();
 
         final ThreadLocalCopies local = keyValueSerializer.threadLocalCopies();
 
diff --git a/src/test/java/net/openhft/chronicle/map/jrs166/map/StatelessChronicleMapTest.java b/src/test/java/net/openhft/chronicle/map/jrs166/map/StatelessChronicleMapTest.java
index b12dda64d..cf4f1b994 100755
--- a/src/test/java/net/openhft/chronicle/map/jrs166/map/StatelessChronicleMapTest.java
+++ b/src/test/java/net/openhft/chronicle/map/jrs166/map/StatelessChronicleMapTest.java
@@ -109,8 +109,6 @@ public class StatelessChronicleMapTest extends JSR166TestCase {
 
         @Override
         public V put(K key, V value) {
-            if (key == null)
-                throw new NullPointerException();
             return d.put(key, value);
         }
 
@@ -206,8 +204,6 @@ public class StatelessChronicleMapTest extends JSR166TestCase {
 
         @Override
         public V putIfAbsent(K key, V value) {
-            if (key == null)
-                throw new NullPointerException();
             return d.putIfAbsent(key, value);
         }