diff --git a/addons/portal/static/src/js/portal_signature.js b/addons/portal/static/src/js/portal_signature.js
index eb58234907c..b0c4690a76b 100644
--- a/addons/portal/static/src/js/portal_signature.js
+++ b/addons/portal/static/src/js/portal_signature.js
@@ -40,6 +40,7 @@ odoo.define('portal.signature_form', function (require){
                 'decor-color': '#D1D0CE',
                 'color': '#000',
                 'background-color': '#fff',
+                'height': '142px',
             });
             this.empty_sign = this.$("#o_portal_signature").jSignature('getData', 'image');
         },
@@ -60,7 +61,7 @@ odoo.define('portal.signature_form', function (require){
             var signature = self.$("#o_portal_signature").jSignature('getData', 'image');
             var is_empty = signature ? this.empty_sign[1] === signature[1] : true;
 
-            this.$('#o_portal_sign_name').toggleClass('has-error', !partner_name);
+            this.$('#o_portal_sign_name').parent().toggleClass('has-error', !partner_name);
             this.$('#o_portal_sign_draw').toggleClass('panel-danger', is_empty).toggleClass('panel-default', !is_empty);
             if (is_empty || ! partner_name) {
                 return false;
@@ -85,8 +86,8 @@ odoo.define('portal.signature_form', function (require){
                 }
                 else if (data.success) {
                     $confirm_btn.remove();
-                    var $prout = qweb.render("portal.portal_signature_success", {widget: data});
-                    self.$('#o_portal_sign_draw').parent().replaceWith($prout);
+                    var $success = qweb.render("portal.portal_signature_success", {widget: data});
+                    self.$('#o_portal_sign_draw').parent().replaceWith($success);
                 }
             });
         },
diff --git a/addons/portal/static/src/xml/portal_signature.xml b/addons/portal/static/src/xml/portal_signature.xml
index a82d7ec89aa..4b0ca5344d1 100644
--- a/addons/portal/static/src/xml/portal_signature.xml
+++ b/addons/portal/static/src/xml/portal_signature.xml
@@ -15,16 +15,16 @@
                 </div>
                 <div id="o_portal_signature" class="panel-body" style="padding: 0"/>
             </div>
-            <div>
-              <button type="submit" class="btn btn-primary o_portal_sign_submit">Sign &amp; Confirm</button>
+            <div class="mt16 pull-right">
+              <button type="submit" class="btn btn-primary o_portal_sign_submit"><t t-esc="widget.options.signLabel or 'Accept &amp; Sign'"/></button>
             </div>
         </form>
     </t>
     <t t-name="portal.portal_signature_success">
         <div class="alert alert-success" role="alert">
-            <strong>Well done!</strong><br />
-            <span t-esc="widget.success_msg"/>
+            <strong>Thank You !</strong><br />
+            <span t-esc="widget.success"/>
             <a t-att-href="widget.redirect_url">Click here to see your document.</a>
         </div>
     </t>
-</templates>
\ No newline at end of file
+</templates>
diff --git a/addons/portal/views/portal_templates.xml b/addons/portal/views/portal_templates.xml
index 80b864183fd..7cb351818fc 100644
--- a/addons/portal/views/portal_templates.xml
+++ b/addons/portal/views/portal_templates.xml
@@ -368,6 +368,7 @@
             t-att-data-res-model="object._name"
             t-att-data-res-id="object.id"
             t-att-data-call-url="callUrl"
+            t-att-data-sign-label="signLabel"
             t-att-data-access-token="accessToken"/>
     </template>
 </odoo>
diff --git a/addons/sale/controllers/portal.py b/addons/sale/controllers/portal.py
index 1f6880c5ada..d78746014c4 100644
--- a/addons/sale/controllers/portal.py
+++ b/addons/sale/controllers/portal.py
@@ -204,18 +204,16 @@ class CustomerPortal(CustomerPortal):
     def portal_quote_accept(self, res_id, access_token=None, partner_name=None, signature=None):
         if request.env['ir.config_parameter'].sudo().get_param(
                 'sale.sale_portal_confirmation_options', default='none') not in ('pay', 'sign'):
-            return False
+            return {'error': _('Operation not allowed')}
+        if not signature:
+            return {'error': _('Signature is missing.')}
         try:
             order_sudo = self._order_check_access(res_id, access_token=access_token)
         except AccessError:
-            return {
-                'error': _('Invalid order')
-            }
-
+            return {'error': _('Invalid order')}
         if order_sudo.state != 'sent':
-            return {
-                'error': _('Order is not in a state requiring customer validation.')
-            }
+            return {'error': _('Order is not in a state requiring customer validation.')}
+
         order_sudo.action_confirm()
 
         _message_post_helper(
diff --git a/addons/sale/views/sale_portal_templates.xml b/addons/sale/views/sale_portal_templates.xml
index 1fbe7a3cdd2..d38b93cb821 100644
--- a/addons/sale/views/sale_portal_templates.xml
+++ b/addons/sale/views/sale_portal_templates.xml
@@ -317,11 +317,12 @@
             <div class="panel-body">
                 <div class="row" t-if="order.state == 'sent' and portal_confirmation == 'sign'" id="portal_sign">
                     <div class="col-md-offset-3 col-md-6">
-                        <h4>Accept order</h4>
+                        <h4>Accept &amp; Sign</h4>
                         <t t-call="portal.portal_signature">
                             <t t-set="object" t-value="order"/>
                             <t t-set="partner_name" t-value="order.partner_id.name"/>
                             <t t-set="callUrl" t-value="'/my/quotes/accept'"/>
+                            <t t-set="signLabel" t-value="'Accept Order'"/>
                             <t t-set="accessToken" t-value="order.access_token"/>
                         </t>
                     </div>