diff --git a/modules/client/back/models/client.js b/modules/client/back/models/client.js
index e66cdb83f..e07993f79 100644
--- a/modules/client/back/models/client.js
+++ b/modules/client/back/models/client.js
@@ -27,7 +27,7 @@ module.exports = Self => {
         message: 'Invalid email',
         allowNull: true,
         allowBlank: true,
-        with: /^[\w|.|-]+@[\w|-]+(\.[\w|-]+)*(,[\w|.|-]+@[\w|-]+(\.[\w|-]+)*)*$/
+        with: /^[\W]*([\w+\-.%]+@[\w\-.]+\.[A-Za-z]{1,61}[\W]*,{1}[\W]*)*([\w+\-.%]+@[\w\-.]+\.[A-Za-z]{1,61})[\W]*$/
     });
 
     Self.validatesLengthOf('postcode', {