diff --git a/templates/frontOffice/default/order-invoice.html b/templates/frontOffice/default/order-invoice.html
index b073956e1..e1fb29b01 100644
--- a/templates/frontOffice/default/order-invoice.html
+++ b/templates/frontOffice/default/order-invoice.html
@@ -150,7 +150,7 @@
                                 <div class="{if $error}has-error{/if}">
                                     <div class="input-group">
                                         <label class="control-label sr-only" for="code">{intl l='Code :'}</label>
-                                        <input id="coupon" class="form-control" type="text" name="{$name}" value="{$value}" placeholder="{intl l='Coupon code'}">
+                                        <input id="coupon" class="form-control" type="text" name="{$name}" value="{$value}" placeholder="{intl l='Coupon code'}" required>
                                         <span class="input-group-btn">
                                             <button type="submit" class="btn btn-coupon">{intl l="Ok"}</button>
                                         </span>