Can I update DCC payments?


As with other standard payments, it is possible to perform updates on DCC payments prior to settlement, by either submitting a TRANSACTIONUPDATE request through our Webservices API or by using MyST.

It is not possible to change the currency of the payment after it has been authorised by the acquiring bank.

It is imperative that all transactions, which use the currency conversions provided by the conversion rate provider, are settled before the dccexpirytimestamp (returned in the CURRENCYRATE response). Failing to do so (e.g. by updating the settlement date) may result in the customer paying the wrong amount and may invalidate your agreement with the conversion rate provider or acquirer.
Deferred settlement is NOT supported for DCC transactions.



Partial settlement of DCC payments

You can submit a TRANSACTIONUPDATE request through our Webservices API or use MyST to update the settle amount of an authorised DCC payment. This can be used to settle a transaction for a lower value than was initially authorised. The remaining funds will be released by the card issuer once the authorisation code has expired (usually approx. 7 days).

The new settle amount is specified in the settlebaseamount field (this represents the amount in the customer’s currency). It must be lower than the total amount authorised in the customer’s currency.

If a partial settlement request has been processed and the customer has made the payment in the customer’s currency, the original conversion rate of the transaction is used to calculate the respective settle amount in the merchant’s currency.


The following is an example of a TRANSACTIONUPDATE request submitted through our Webservices API to lower the final settle amount for a DCC payment:

import securetrading
stconfig = securetrading.Config()
stconfig.username = "[email protected]"
stconfig.password = "Password1^"
st = securetrading.Api(stconfig)
update = {
  "requesttypedescriptions": ["TRANSACTIONUPDATE"],
    "sitereference": [{"value":"test_site12345"}],
    "transactionreference": [{"value":"1-2-3"}]
strequest = securetrading.Request()
stresponse = st.process(strequest) #stresponse contains the transaction response
if (!($autoload = realpath(__DIR__ . '/../../../autoload.php')) && !($autoload = realpath(__DIR__ . '/../vendor/autoload.php'))) {
  throw new Exception('Composer autoloader file could not be found.');
$configData = array(
  'username' => '[email protected]',
  'password' => 'Password1^',
$requestData = array(
'requesttypedescriptions' => array('TRANSACTIONUPDATE'),
'filter' => array(
  'sitereference' => array(array('value' => 'test_site12345')),
  'transactionreference' => array(array('value' => '1-2-3'))
'updates' => array('settlebaseamount' => '960')
$api = \Securetrading\api($configData);
$response = $api->process($requestData);
curl --user [email protected]:Password1^ <DOMAIN>/json/ -H "Content-type: application/json" -H "Accept: application/json" -X POST -d '{
"alias": "[email protected]",
"version": "1.00",
"request": [{
  "requesttypedescriptions": ["TRANSACTIONUPDATE"],
    "sitereference": [{"value":"test_site12345"}],
    "transactionreference": [{"value":"1-2-3"}]
{"alias":"[email protected]","version":"1.00","request":[{"requesttypedescriptions":["TRANSACTIONUPDATE"],"filter":{"sitereference":[{"value":"test_site12345"}],"transactionreference":[{"value":"1-2-3"}]},"updates":{"settlebaseamount":"960"}}]}
<?xml version='1.0' encoding='utf-8'?>
<requestblock version="3.67">
  <alias>[email protected]</alias>
  <request type="TRANSACTIONUPDATE">

Replace <DOMAIN> with a supported domain. Click here for a full list.