diff --git a/htdocs/societe/card.php b/htdocs/societe/card.php
index af134dcd354..be9ff83cb45 100644
--- a/htdocs/societe/card.php
+++ b/htdocs/societe/card.php
@@ -1367,10 +1367,13 @@ else
 
             if (! empty($conf->use_javascript_ajax))
             {
+            	$widthpopup = 600;
+            	if ( empty($conf->dol_use_jmobile)) $widthpopup = 350;
+            	$heightpopup = 400;
                 print "\n";
                 print '<script language="JavaScript" type="text/javascript">';
                 print "function CheckVAT(a) {\n";
-                print "newpopup('".DOL_URL_ROOT."/societe/checkvat/checkVatPopup.php?vatNumber='+a,'".dol_escape_js($langs->trans("VATIntraCheckableOnEUSite"))."', 540, 350);\n";
+                print "newpopup('".DOL_URL_ROOT."/societe/checkvat/checkVatPopup.php?vatNumber='+a,'".dol_escape_js($langs->trans("VATIntraCheckableOnEUSite"))."', '.$widthpopup.', '.$heightpopup.');\n";
                 print "}\n";
                 print '</script>';
                 print "\n";