From where is the checkout billing address options drop down being populated? How can I control the options? EDIT: Found **root/vendor/magento/module-checkout/view/frontend/web/js/view/billing-address.js** var lastSelectedBillingAddress = null, newAddressOption = { /** * Get new address label * @returns {String} */ getAddressInline: function () { return $t('New Address'); }, customerAddressId: null }, countryData = customerData.get('directory-data'), addressOptions = addressList().filter(function (address) { return address.getType() == 'customer-address'; //eslint-disable-line eqeqeq }); addressList then is **'Magento_Customer/js/model/address-list'** Found the template as well **root/vendor/magento/module-checkout/view/frontend/web/template/billing-address/list.html** <div class="field field-select-billing"> <label class="label"><span data-bind="i18n: 'My billing and shipping address are the same'"></span></label> <div class="control" data-bind="if: (addressOptions.length > 1)"> <select class="select" name="billing_address_id" data-bind=" options: addressOptions, optionsText: addressOptionsText, value: selectedAddress, event: {change: onAddressChange(selectedAddress())}; "></select> </div> </div> **This is database information so php has to bring it. Where in php are these values passed to knockout?** [![enter image description here][1]][1] [1]: https://i.sstatic.net/blQBS.png