Question to the HM Treasury:

To ask His Majesty's Government, with regard to page 39 of their policy paper Spending Review 2025: Departmental Efficiency Plans, published on 11 June, how many legacy IT systems and platforms are (1) currently operated by HMRC; and (2) scheduled for decommissioning by 2028–29 under the software as a service transition strategy.

HMRC is in the process of finalising its implementation plan of the Spending Review 2025 following receipt of the settlement. The department is planning the sequencing and prioritisation of activity to ensure they can deliver the departments commitments, tackle technical debt and mitigate risks. This will include assessing the impact of legacy IT systems and platforms as part of the Software as a Service (SaaS) transition strategy.

HMRC is taking a phased approach to meet its efficiency target whilst balancing and maintaining operational resilience. To support this, HMRC has undertaken a detailed assessment of its digital estate, which includes over 4 million physical assets (i.e., network equipment, disk arrays, servers, laptops, desktops).

The complex IT estate HMRC operates requires careful coordination to identify systems for decommissioning or migration by 2028-29. Therefore, decommissioning and upgrading activities are being delivered through several different change programmes. The long-term delivery plan will be finalised in the autumn, at which point there will be a clearer indication of the number of IT systems which will be decommissioned by 2028-29.