diff --git a/CHANGES.rst b/CHANGES.rst
index 03ed63f4cd..4fce6d5129 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -26,6 +26,7 @@ Changelog
 
 **Fixed**
 
+- #670 Listings: Fix sort_on change on Show More click
 - #653 Points in QC Charts are not displayed in accordance with capture date
 - #662 Viewing Cancelled AR's fails
 - #550 Wrong Listings of Analyses called from Dashboard
diff --git a/bika/lims/browser/templates/bika_listing_table.pt b/bika/lims/browser/templates/bika_listing_table.pt
index 4f1ab1c49a..d210c79669 100644
--- a/bika/lims/browser/templates/bika_listing_table.pt
+++ b/bika/lims/browser/templates/bika_listing_table.pt
@@ -86,12 +86,12 @@
     <input type="hidden"
            tal:omit-tag="python:table_only"
            tal:attributes="name python:form_id+'_sort_on';
-                           value python:request.get(form_id+'_sort_on', 'id')"/>
+                           value python:request.get(form_id+'_sort_on', '')"/>
 
     <input type="hidden"
            tal:omit-tag="python:table_only"
            tal:attributes="name python:form_id+'_sort_order';
-                           value python:request.get(form_id+'_sort_order', 'ascending')"/>
+                           value python:request.get(form_id+'_sort_order', '')"/>
 
     <input type="hidden"
            name="ajax_categories"