There are a few different methods to accomplish this:
Method 1. Use a mixin to override the isBaseGrandTotalDisplayNeeded
method in Magento_Tax/js/view/checkout/summary/grand-total
Vendor/Module/view/frontend/requirejs-config.js
var config = {
'config': {
'mixins': {
'Magento_Tax/js/view/checkout/summary/grand-total': {
'Vendor_Module/js/grand-total-mixin': true
}
}
}
};
Vendor/Module/view/frontend/js/grand-total-mixin.js
define(function () {
'use strict';
var mixin = {
isBaseGrandTotalDisplayNeeded: function () {
// you custom logic for displaying base grand total
// returning false prevents the section from being displayed
return false;
}
};
return function (target) {
return target.extend(mixin);
};
});
Method 2. Override Magento_Tax/template/checkout/summary/grand-total.html
using a module or theme and remove the section of the template you don't want.
Using a module:
Vendor/Module/view/frontend/requirejs-config.js
var config = {
map: {
'*': {
'Magento_Tax/template/checkout/summary/grand-total.html':
'Vendor_Module/template/checkout/summary/grand-total.html'
}
};
Vendor/Module/view/frontend/web/template/checkout/summary/grand-total.html
Below is the template with the base grand total display removed.
<!--
/**
* Copyright © 2013-2017 Magento, Inc. All rights reserved.
* See COPYING.txt for license details.
*/
-->
<!-- ko if: isTaxDisplayedInGrandTotal && isDisplayed() -->
<tr class="grand totals incl">
<th class="mark" scope="row">
<strong data-bind="i18n: inclTaxLabel"></strong>
</th>
<td data-bind="attr: {'data-th': inclTaxLabel}" class="amount">
<strong><span class="price" data-bind="text: getValue()"></span></strong>
</td>
</tr>
<tr class="grand totals excl">
<th class="mark" scope="row">
<strong data-bind="i18n: exclTaxLabel"></strong>
</th>
<td data-bind="attr: {'data-th': exclTaxLabel}" class="amount">
<strong><span class="price" data-bind="text: getGrandTotalExclTax()"></span></strong>
</td>
</tr>
<!-- /ko -->
<!-- ko if: !isTaxDisplayedInGrandTotal && isDisplayed() -->
<tr class="grand totals">
<th class="mark" scope="row">
<strong data-bind="i18n: title"></strong>
</th>
<td data-bind="attr: {'data-th': title}" class="amount">
<strong><span class="price" data-bind="text: getValue()"></span></strong>
</td>
</tr>
<!-- /ko -->
The same template above can be placed directly in a custom theme without the module or requirejs-config by placing in app/design/Vendor/Package/Magento_Tax/web/template/checkout/summary/grand-total.html