The National Infrastructure and Service Transformation Authority has published its Major Projects Annual Report 2025-26, covering delivery performance across the Government Major Projects Portfolio in the year to March 2026 – the period immediately before a significant restructure of how the portfolio is managed.
At the end of March 2026, 29 projects (15%) held a Green rating, 109 (58%) Amber, and 34 (18%) Red, with 17 projects exempt from rating. NISTA is clear that Red ratings disproportionately reflect the most ambitious and complex programmes in the portfolio rather than straightforward delivery failure, and that targeted support is being deployed to address risks before they escalate.
During the review period, 42 projects left the portfolio altogether, with 26 having successfully delivered against their objectives. A further 18 projects improved from Amber to Green, and one moved directly from Red to Green. Seven projects were brought to early closure.
For the construction and infrastructure supply chain, the most significant developments in the report relate to structural changes in how government manages and monitors its largest programmes. From 1 April 2026, NISTA restructured the GMPP into a more focused list of 81 nationally significant projects, with other major projects moving into strengthened departmental oversight through Departmental Major Projects Portfolios.
The report also introduces a new mega project classification for the most complex and strategically significant programmes – defined as those with whole-life costs typically exceeding £10 billion and spanning multiple parliaments. Three projects have been granted this status at launch: Sizewell C, HS2 and Dreadnought. The classification signals a differentiated oversight and support regime for programmes of this scale and duration, with direct implications for how supply chain relationships on those projects are likely to be managed.
NISTA has also deployed an AI-powered Early Warning System, drawing on existing GMPP data to identify projects at risk of moving to a Red rating before problems become entrenched. The tool is being embedded into review processes and represents a shift toward more proactive, data-driven programme assurance.
Becky Wood, Chief Executive of NISTA, framed the ratings as early warning signals rather than definitive verdicts, emphasising that the purpose of the oversight regime is to identify risks sooner and get the right support in place at the right time.
For businesses operating in the major projects supply chain, the report reinforces the direction of travel: greater transparency, more structured performance monitoring, and a government increasingly focused on getting delivery right before problems compound – a framework that raises the bar on contractor performance data, programme controls and risk management capability.
