The delivery of high-value construction programmes is accelerating globally, but new analysis has revealed how far behind the UK trails other countries.
According to Mace’s 2025 report The Future of Major Programme Delivery, there has been a 280 per cent increase in the number of live megaprojects – those valued over $1bn (£733m) – worldwide over the past 15 years.
Over 11,000 megaprojects and 250 gigaprojects (over $10bn) are in progress worldwide, representing more than $15tn in capital investment, Mace said.
The US leads with 1,663 mega and gigaprojects announced since 2010, more than three times as many as the UK in fourth place with 484.
But while the UK ranks among the top countries by volume of $1bn-plus projects, Mace’s data suggests that it underperforms in terms of delivery speed.
The report, published this morning (3 July), found that the UK has one of the longest average delivery times globally for megaprojects at nearly 12.5 years, compared with just under nine years in both the US and Saudi Arabia.
Ireland has the shortest average at 5.8 years.
The UK performs “particularly poorly” on infrastructure delivery with a mean average of 19 years from announcement to completion, Mace added.
Mace attributed the UK’s extended timelines to “high levels of bureaucracy, challenges in gaining project consents and stop-start funding as part of budgeting cycles”.
These challenges were echoed in interviews conducted for the report, which draws on a dataset of more than 5,000 mega and gigaprojects across 12 countries.
Compared with the UK, it found that other mature markets like Ireland and Hong Kong demonstrate comparatively low levels of project risk, which the report links to clearer pipelines and more effective governance structures.
“Within the UK, we see a parochial approach to planning and consenting which creates substantial inefficiency,” said Phil Brown, managing director of major nuclear capital programmes at Babcock International.
“For example, we are often required to do additional (nugatory) work to demonstrate compliance with a specific requirement of the planning process… This wasted effort and inefficiency adds little value, increases costs and delays programmes.”
Official reports have identified systemic issues with the delivery of UK infrastructure projects.
In a report published last October, for instance, the National Infrastructure Commission – now replaced by the National Infrastructure and Service Transformation Authority – described a lack of clear strategic direction from the government, slow consenting processes and funding uncertainty as major delivery barriers.
Mace said: “Bureaucratic consenting processes, where the average time taken to secure approval doubled between 2009 and 2019, is another underlying issue. Along with the obvious impact on timelines, this comes at a cost.”
The Mace report cites how other countries – such as Saudi Arabia with its Vision 2030 strategy – are adopting collaborative delivery models supported by integrated delivery teams to improve outcomes. In the US, programmes such as the Hudson Tunnel Project are using delivery partner models to streamline execution and reduce risk.
Mace highlighted the London 2012 Olympics construction programme as a historical example of successful collaborative delivery in the UK, noting it was completed a year early and £600m under its £9.3bn budget.
But despite this precedent, the report observed that such models remain underused in the UK.
Referring to the 2012 Olympics, Mace Consult chief executive Davendra Dabasia said: “Instead of applying and building on that model’s proven performance, and following the general consensus that collaborative models lead to better outcomes, our industry continues to face significant challenges managing and delivering on promises.”
The government released an infrastructure plan and industrial strategy last month but its promised 10-year, £725bn infrastructure pipeline is yet to be unveiled.