Select committee: Public Accounts Committee
Conclusion 25
23rd Report - The cost of the tax system
Published 30 Apr 2025
Addressed to HM Treasury
Public Accounts Committee The cost of the tax system All items in this report Report on parliament.uk ↗ Inquiry on parliament.uk ↗
Conclusion (the committee's words)
We asked HMRC why it had taken longer and was costing more to remediate its legacy systems. HMRC said that some of the systems had proved more complex than expected and it had underestimated costs.45 Progress had also been slowed by HMRC transferring some funding for one of its remediation programmes in 2023–24 to higher priorities.46 We asked HMRC whether it now understands what more it needs to do, what it will cost and when it expects remediation to be complete. HMRC said that it had a good understanding of what it needed to do and had a plan. But it was unable to say when it would complete remediation because funding for the three years after 2025–26 would not be known until it had its spending review settlement in June 2025.47
From: Public Accounts Committee, 23rd Report - The cost of the tax system (HC 645), 30 April 2025
Government response
The government responded to the whole report on 18 September 2025.
Summary written by Accountability Index from the government's response. It is not the government's own words.The government states that it "agrees with the Committee's recommendation" on each of the report's recommendations, and reports that several are already implemented while others carry target dates.
- On simplification, the government will publish HMRC's Transformation Roadmap in summer 2025, which "will include the metrics HMRC will use to report progress".
- On trust, the government agrees with both recommendations and describes them as "Recommendation implemented", citing annual customer surveys, complaints data and focus groups.
- On compliance productivity, it says HMRC "will recruit an additional 5,500 compliance staff by March 2030", alongside other measures to close the tax gap.
- On legacy IT, HMRC "will write to the Committee" on its remediation plans, forecast cost and expected savings, with a target implementation date of September 2025.