diff --git a/app/assets/error_pages/5xx.html b/app/assets/error_pages/5xx.html
index f456dde74..25ea83e21 100644
--- a/app/assets/error_pages/5xx.html
+++ b/app/assets/error_pages/5xx.html
@@ -127,10 +127,10 @@
 
     <script>
       if (window.GOVUK.cookie('_ga') !== null) {
-        document.cookie = '_ga' + '=;expires=' + new Date() + ';domain=.' + window.location.hostname + ';path=/';
+        document.cookie = '_ga' + '=;expires=' + new Date() + ';domain=' + window.location.hostname.replace(/^www\./, '.') + ';path=/';
       }
       if (window.GOVUK.cookie('_gid') !== null) {
-        document.cookie = '_gid' + '=;expires=' + new Date() + ';domain=.' + window.location.hostname + ';path=/';
+        document.cookie = '_gid' + '=;expires=' + new Date() + ';domain=' + window.location.hostname.replace(/^www\./, '.') + ';path=/';
       }
     </script>
 
diff --git a/app/templates/admin_template.html b/app/templates/admin_template.html
index c7b3954d9..fc709c298 100644
--- a/app/templates/admin_template.html
+++ b/app/templates/admin_template.html
@@ -237,10 +237,10 @@
   <!--<![endif]-->
   <script>
     if (window.GOVUK.cookie('_ga') !== null) {
-      document.cookie = '_ga' + '=;expires=' + new Date() + ';domain=.' + window.location.hostname + ';path=/';
+      document.cookie = '_ga' + '=;expires=' + new Date() + ';domain=' + window.location.hostname.replace(/^www\./, '.') + ';path=/';
     }
     if (window.GOVUK.cookie('_gid') !== null) {
-      document.cookie = '_gid' + '=;expires=' + new Date() + ';domain=.' + window.location.hostname + ';path=/';
+      document.cookie = '_gid' + '=;expires=' + new Date() + ';domain=' + window.location.hostname.replace(/^www\./, '.') + ';path=/';
     }
   </script>
 {% endblock %}
diff --git a/paas-failwhale/index.html b/paas-failwhale/index.html
index d1906c32b..cbb41ccb7 100644
--- a/paas-failwhale/index.html
+++ b/paas-failwhale/index.html
@@ -128,10 +128,10 @@
 
     <script>
       if (window.GOVUK.cookie('_ga') !== null) {
-        document.cookie = '_ga' + '=;expires=' + new Date() + ';domain=.' + window.location.hostname + ';path=/';
+        document.cookie = '_ga' + '=;expires=' + new Date() + ';domain=' + window.location.hostname.replace(/^www\./, '.') + ';path=/';
       }
       if (window.GOVUK.cookie('_gid') !== null) {
-        document.cookie = '_gid' + '=;expires=' + new Date() + ';domain=.' + window.location.hostname + ';path=/';
+        document.cookie = '_gid' + '=;expires=' + new Date() + ';domain=' + window.location.hostname.replace(/^www\./, '.') + ';path=/';
       }
     </script>