WorldPay's 'deferred payments' feature (also know as 'pre-authorisation') enables you to freeze a transaction when the shopper pays, to delay the movement of funds from their card. You can then make some extra checks (for example, on your levels of stock, or about the shopper), before taking payment and making delivery, or deciding to cancel the order.
How does Deferred Payment work?

For a deferred payment transaction, when a shopper decides to purchase goods/services at your site:
1 you decide to defer payment for this shopper's purchase (and ensure that your site handles this shopper's transaction as a deferred payment transaction)
2 the shopper enters their card details
3 WorldPay make the usual checks (with the card issuer) on the payment details entered
4 if the card payment is authorised, the funds are merely reserved against the shopper's card, so payment is not yet taken from their account (this is then a 'pre-authorised' transaction)
5 when ready, you complete ('post-authorise') the transaction - and actually take payment from the cardholder's account; you also pay any transaction fees due, at this point
6 you supply the goods/services to the shopper

For a standard purchase, or 'Fully-Authorised' transaction (-> diagram), you just send details of the shopper's purchase to WorldPay - with no alert about deferring payment. Then, at step 4 you take the funds from the shopper's account, and (as there is no need to post-authorise the transaction) you then supply the goods/services.

Note:
Some shopping cart solutions will not support WorldPay's deferred processing service for your website. Please contact your shopping cart provider to check that they will support deferred payment.

Do Shoppers notice any difference?
No. As far as the shopper is concerned, they have paid for the order and the deferred payment transaction appears to them as a standard transaction. They will expect the funds to be taken from their card (possibly after a short delay), as usual.

Why defer payment?
When you pre-authorise a transaction - to defer payment, you get some time to:
- restock goods that are not yet available
- check for duplicate orders, before these go to the bank for settlement
- make further anti-fraud checks before you supply goods/services

Note:
For transactions based in the USA, US law requires 2-stage transaction processing, as funds may not be taken from shoppers' cards until the goods have been dispatched. Thus you have to accept all transactions via the deferred payment route.

How can I decide to defer payment?
There are many approaches to deferring payment. In order of technical complexity, you could:
1 defer payment for all of your transactions, and then complete these individually within WorldPay's Customer Management System (CMS), or
2 as for option 1, but if you have a large number of transactions, then add some automatic processing of completions (see below)
3 analyse the details of the shopper and their purchase - before they start to pay at WorldPay's payment pages. Then use a filter to divert special cases into your 'defer payment route', and enable these shoppers to pay via a transaction that your systems see as pre-authorised. Finally, complete (post-authorise) these transactions, either individually within the CMS, or via some automatic processing (see below)
4 possibly in combination with option 3, you could enable automatic post-authorisation/settlement of a transaction after the card details are verified. You could do this by automated checking of callback information, to decide if the transaction was ready for completion.

Note:
if you handle hundreds or thousands of transactions daily, then you would need to use option 4 to cope with the processing required. You would also need to use 'remote post-authorisation' - requiring a complex arrangement of features and installations at your server and at WorldPay; please contact your local WorldPay Technical Support team for more information.

Will the deferred funds always be available?
Yes, unless the card account becomes suspended (due to the card being reported as lost/stolen). Funds reserved from a pre-authorised transaction are not available for the shopper to re-spend. So, although the shopper may see no debit from their card account on the date of the pre-authorised transaction, the funds have been reserved for your future debit. For example, if a shopper with €100 available on their card spends €60 at your site for a pre-authorised purchase, their card account would still show a balance of €100 (but €60 is now reserved for your payment). If they then try to spend over €40, the card-issuer will prevent this. Thus you can be sure that enough funds will be available, if you decide to complete/post-authorise the transaction and the card account is still active.

How long can I defer payment?
You have 5 days from when the transaction was pre-authorised. If you do not complete the transaction after 5 days, then:
- the transaction will end (or 'time out')
- the Shopper is not debited - the funds for the transaction are no longer reserved and you do not receive payment
- you must inform the shopper that you will not complete their order

How do I complete, after deferring payment?
When you have pre-authorised a transaction to defer its payment, you need to complete (or post-authorise) the transaction. From within our Customer Management System (CMS), you can either:
- search for and complete an individual transaction, or
- view the transactions awaiting completion in an account, and select transactions to be completed

Note:
For statements of transactions within the CMS, the Trans Status column shows:
- "Authorised" for Pre-authorised transactions
- "Completed" or "Timed Out" for Post-authorised transactions

Can I automatically complete (post-authorise) transactions?
Yes - but this is a technically complex area. For more details, see Remote Admin.

Can I complete - but for a smaller amount/order?
No. You can only complete the payment, or allow the payment to lapse. There is no way you can take less than the full amount that was reserved against the shopper's card, so 'partial completion' is not possible. However, you could allow the deferred payment to lapse, and then enable the shopper to re-order; or you could complete for the full amount and then make a partial refund.

How can I start using Deferred Processing?
1: Apply for the service
To install and operate our deferred processing services on your website, you need: a high level of technical programming skills two sets of settlement accounts (if you want to use both pre-authorisation and standard/full authorisation to process transactions) To apply for deferred processing services, contact your local WorldPay Technical Support team, or email: pre-auth@worldpay.com (please include details of WorldPay accounts and installations).
2: Make changes to your Purchase Token
When we have enabled pre-authorisation for your installation, to defer payment for a transaction, you need to include an "authMode" parameter (set to "E") in the purchase token that you send to WorldPay. Or you can preset all transactions to use deferred processing, by selecting this as the default within our Customer Management System. If you use a shopping cart, then these settings and changes may be made automatically by the cart.

How is Deferred Payment different from a standard transaction?
Deferred Payment does not affect the emails sent to you or the shopper - to confirm the payment (and order) details. Any callbacks to your server are also unaffected.