The required sequence of API requests and responses — calls and callbacks — for payments is largely dependent on the selected bank and the use cases each bank currently supports.
Important: If you are currently using a version of the Token SDK for TPPs earlier than v2.8.6 (released 26 March 2020), there are important changes to the flows you will need to consider if you plan to connect with:
- Banks outside the UK (excluding the Republic of Ireland and Poland)
- Banks in Germany and Austria
Two distinct payment flow categories have been introduced with the release of SDK version 2.8.6:
- 2-step (TPP-initiated) Payments – requires transfer token redemption by the TPP; after submitting transfer request, TPP must explicitly redeem transfer token to execute payment.
- 1-step (bank-initiated) Payments – immediate transfer token redemption by the bank; TPP does not need to submit an explicit token redemption request to execute payment.
The changes are designed to standardise the user experience across different permutations in the payment flow imposed by various banks throughout Europe. The changes that will impact your implementation largely depend on how you currently integrate with Token.
In general, if you take payments from across the UK and Europe, you will need to support both payment flows. If you take payments from within a single country only, it may be possible to support only one flow, although this is largely bank-dependent as described is due course later in this topic. In all cases, you will be wise to double-check each bank's particular requirements.
Click on one of the following links to go directly to the use case that applies to you: