Full migration programs – key considerations

Full migration replaces existing non-ISO20022 (typically MT) based systems and IT architecture, with platforms and a data strategy built around ISO20022. Such a migration typically involves change and consolidation in almost all components of the organisation’s payment systems, and is delivered across a complex, multi-phase and multi-year IT transformation program.

Due to the complexity of such an undertaking, full migrations present a number of challenges; some of which are unforeseen and only uncovered or realised well after the commitment to change has been made.



Upgrading payment processing applications to be ISO native ensures that all internal components speak the same language, eliminating risk of truncation, and making optimal use of automation & business intelligence opportunities. The implications of choosing ISO20022 as the internal data language should be carefully considered, as the impact extends well beyond the banks’ core payment applications. However, the use of a common internal language across business processes allows banks to leverage rich data across business processes in order to improve straight through processing capabilities, back office efficiency, and business insights.


Deeply intertwined, and often heavily customised solutions can be costly to upgrade or replace. Payment engines, reporting systems, screening products, back office tools, channels – everything needs to be adapted, and interoperability needs to be ensured. The teams involved in managing and operating each of these tools needs to become intimately familiar with ISO20022 data structures; as do corporate customers looking to leverage the data language for their payment initiation and reporting.

Competition for resources

Even after budgets and internal resources have been secured, replacing core systems often requires external resources such as consultants from solution providers, system integrators, and analysts specialised in payments. Competition for such profiles will drive prices up and availability down, particularly during the multiple overlapping global and domestic initiatives. Similarly, internal to each organisation, resource demand for re-platforming will be at a premium, and consideration must be given as to priorities in particular to any product development and new customer propositions beyond the ISO20022 compliance and platform upgrade programs.

Time to market

Reviewing and replacing the full stack of payment systems is a large project, for which testing alone can take months and years. Corporate customers expect the improved experience ISO provides, and early adopter banks can expect to win market share. When facing short and intransigent deadlines for migration, banks should take care to analyse their confidence in a timely delivery and realise that there is considerable time spent in merely replacing much of the existing functionality, and that as with most large and lengthy IT projects, there is inherent time and budget risk, and the inevitable unknowns which get found out once the project is well underway


Payment engine upgrades can negatively impact the correct and timely processing of payments, with catastrophic impact on corporate customers. It also comes with a risk to data integrity, as siloed legacy systems typically mean no single source of data truth and the potential to ‘lose’ critical data and functions during the upgrade process. Upgrading multiple systems synchronously compounds these risks and presents other challenges in terms of understanding existing and underlying functionality, which over the course of time has developed beyond the original vendor platform and requires analysis and mapping into target architecture and systems.


Whereas full migration programs are arguably the most robust and future-proof, they are often also the most costly and time-consuming, and come with their own set of risks and technical challenges. As such, they are best suited to organisations that are:

  • Major payment hubs which process significant payment volumes, and where the investment in automation opportunities and operating model improvements can offset the inherent risks, challenges and costs of re-platforming merely for ISO compliance.

  • Organisations that have existing well-structured payment systems, rather than patchwork and duplicated payment processing solutions, or organisations which have already commenced a broader transformation program, which would allow for a far simpler upgrade path to ISO compliance.

  • Organisations with less stringent deadlines for migrating to ISO standards, where the costs and risks with ISO can be better managed, and where other benefits such as better customer products and propositions can be used to justify the investment case for re-platforming above the soft benefits of ISO20022.