diff --git a/addons/web_im/static/src/js/im.js b/addons/web_im/static/src/js/im.js
index 9cb70e7d21c..87a048dd14a 100644
--- a/addons/web_im/static/src/js/im.js
+++ b/addons/web_im/static/src/js/im.js
@@ -353,6 +353,7 @@ openerp.web_im = function(instance) {
             this.user.add_watcher();
             this.set("right_position", 0);
             this.shown = true;
+            this.set("pending", 0);
         },
         start: function() {
             var change_status = function() {
@@ -366,6 +367,13 @@ openerp.web_im = function(instance) {
             this.on("change:right_position", this, this.calc_pos);
             this.full_height = this.$el.height();
             this.calc_pos();
+            this.on("change:pending", this, _.bind(function() {
+                if (this.get("pending") === 0) {
+                    this.$(".oe_im_chatview_nbr_messages").text("");
+                } else {
+                    this.$(".oe_im_chatview_nbr_messages").text("(" + this.get("pending") + ")");
+                }
+            }, this));
         },
         show_hide: function() {
             if (this.shown) {
@@ -378,11 +386,19 @@ openerp.web_im = function(instance) {
                 });
             }
             this.shown = ! this.shown;
+            if (this.shown) {
+                this.set("pending", 0);
+            }
         },
         calc_pos: function() {
             this.$el.css("right", this.get("right_position"));
         },
         received_message: function(message) {
+            if (this.shown) {
+                this.set("pending", 0);
+            } else {
+                this.set("pending", this.get("pending") + 1);
+            }
             this._add_bubble(this.user, message.message, message.date);
         },
         send_message: function(e) {
diff --git a/addons/web_im/static/src/xml/im.xml b/addons/web_im/static/src/xml/im.xml
index 118bbd85f13..3d42c717174 100644
--- a/addons/web_im/static/src/xml/im.xml
+++ b/addons/web_im/static/src/xml/im.xml
@@ -32,6 +32,7 @@
             <div class="oe_im_chatview_header">
                 <img t-att-src="_s +'/web_im/static/src/img/green.png'" class="oe_im_chatview_online"/>
                 <t t-esc="widget.user.get('name') || 'Anonymous'"/>
+                <scan class="oe_im_chatview_nbr_messages" />
                 <button class="oe_im_chatview_close">×</button>
             </div>
             <div class="oe_im_chatview_disconnected">