diff --git a/addons/account_payment/views/account_portal_templates.xml b/addons/account_payment/views/account_portal_templates.xml
index 0c7ddc0ce88..e9d121e15e0 100644
--- a/addons/account_payment/views/account_portal_templates.xml
+++ b/addons/account_payment/views/account_portal_templates.xml
@@ -8,7 +8,7 @@
                 <t t-set="tx_ids" t-value="invoice.transaction_ids.filtered(lambda tx: tx.state in ('pending', 'authorized', 'done'))"/>
                 <t t-set="pending_manual_txs" t-value="tx_ids.filtered(lambda tx: tx.state == 'pending' and tx.acquirer_id.provider in ('transfer', 'manual'))"/>
                 <a t-if="invoice.state == 'open' and invoice.amount_total and invoice.type == 'out_invoice' and (pending_manual_txs or not tx_ids)"
-                    t-att-href="invoice.get_portal_url(anchor='portal_pay')" title="Pay now" aria-label="Pay now" class="btn btn-sm btn-success" role="button">
+                    t-att-href="invoice.get_portal_url(anchor='portal_pay')" title="Pay now" aria-label="Pay now" class="btn btn-sm btn-primary" role="button">
                     <i class="fa fa-arrow-circle-right"/><span class='d-none d-md-inline'> Pay Now</span>
                 </a>
             </td>
@@ -72,7 +72,7 @@
             <t t-set="pending_manual_txs" t-value="tx_ids.filtered(lambda tx: tx.state == 'pending' and tx.acquirer_id.provider in ('transfer', 'manual'))"/>
             <div>
                 <a href="#" t-if="invoice.state == 'open' and invoice.amount_total and invoice.type == 'out_invoice' and (pending_manual_txs or not tx_ids)"
-                    class="btn btn-success btn-block mb-2" data-toggle="modal" data-target="#pay_with">
+                    class="btn btn-primary btn-block mb-2" data-toggle="modal" data-target="#pay_with">
                     <i class="fa fa-fw fa-arrow-circle-right"/> Pay Now
                 </a>
                 <div t-if="tx_ids and not pending_manual_txs and invoice.state != 'paid'" class="alert alert-info py-1 mb-2" >
diff --git a/addons/sale/views/sale_portal_templates.xml b/addons/sale/views/sale_portal_templates.xml
index edf02279b0f..ca1fde9bc49 100644
--- a/addons/sale/views/sale_portal_templates.xml
+++ b/addons/sale/views/sale_portal_templates.xml
@@ -132,10 +132,10 @@
                     <t t-set="entries">
                         <ul class="list-group list-group-flush flex-wrap flex-row flex-lg-column">
                             <li class="list-group-item flex-grow-1">
-                                <a t-if="sale_order.has_to_be_signed(True)" role="button" t-attf-class="btn btn-{{ 'primary' if sale_order.has_to_be_paid() else 'success'}} btn-block mb8" data-toggle="modal" data-target="#modalaccept" href="#">
+                                <a t-if="sale_order.has_to_be_signed(True)" role="button" class="btn btn-primary btn-block mb8" data-toggle="modal" data-target="#modalaccept" href="#">
                                     <i class="fa fa-check"/> Accept &amp; Sign
                                 </a>
-                                <a t-elif="sale_order.has_to_be_paid(True)" role="button" class="btn btn-success btn-block mb8" data-toggle="modal" data-target="#modalaccept" href="#">
+                                <a t-elif="sale_order.has_to_be_paid(True)" role="button" class="btn btn-primary btn-block mb8" data-toggle="modal" data-target="#modalaccept" href="#">
                                     <i class="fa fa-check"/> <t t-if="not sale_order.signature">Accept &amp; Pay</t><t t-else="">Pay now</t>
                                 </a>
                                 <div class="o_download_pdf btn-toolbar flex-sm-nowrap">
@@ -324,7 +324,7 @@
 
                         <t t-if="sale_order.has_to_be_signed(True)">
                             <div class="col-sm-auto mt8">
-                                <a role="button" t-attf-class="btn btn-{{ 'primary' if sale_order.has_to_be_paid() else 'success'}}" data-toggle="modal" data-target="#modalaccept" href="#"><i class="fa fa-check"/> Accept &amp; Sign</a>
+                                <a role="button" class="btn btn-primary" data-toggle="modal" data-target="#modalaccept" href="#"><i class="fa fa-check"/> Accept &amp; Sign</a>
                             </div>
                             <div class="col-sm-auto mt8">
                                 <a role="button" class="btn btn-secondary" href="#discussion"><i class="fa fa-comment"/> Feedback</a>
@@ -334,7 +334,7 @@
                             </div>
                         </t>
                         <div t-elif="sale_order.has_to_be_paid(True)" class="col-sm-auto mt8">
-                            <a role="button" class="btn btn-success" data-toggle="modal" data-target="#modalaccept" href="#">
+                            <a role="button" class="btn btn-primary" data-toggle="modal" data-target="#modalaccept" href="#">
                                 <i class="fa fa-check"/> <t t-if="not sale_order.signature">Accept &amp; Pay</t><t t-else="">Pay now</t>
                             </a>
                         </div>