UK rail cost review to test how speed and capacity are specified

An independent review led by Rachel Skinner will examine why rail infrastructure costs so much to build in the UK, the Department for Transport has confirmed. Its terms of reference, published on 28 October, ask for recommendations within six months of the review being set up.

The Department for Transport says the review should "identify the key drivers of cost in the sector and recommend tangible solutions for government and industry to implement". The government first announced it in its Northern Growth Strategy, and the Chancellor repeated the commitment in a growth speech in September.

Skinner, who holds a CBE, has been "empowered to produce recommendations they deem necessary to reduce the cost of delivering railways", the document states. She will be supported by a delivery team and an expert panel drawn from academia and from people with long UK and international rail careers.

Speed, capacity and the timing of decisions

The scope focuses on the design and delivery phases of projects. It covers how schemes are started, how their speed and capacity are specified, and whether the client side can challenge "excess costs or overspecification" using national and international benchmarks. It also asks whether decisions on scope, affordability and value for money are taken once designs are mature enough and costs reasonably certain.

The review will also look at the regulatory environment. That includes the planning and consenting regime, with Nationally Significant Infrastructure Projects, Transport and Works Act Orders and the Planning and Infrastructure Act, as well as how safety standards are applied in design. Another strand covers procurement, risk allocation and whether devolution to mayors can deliver schemes more cheaply.

The client for the review is the policy and benefits director of the Major Rail Projects Group. A client panel brings together the Department for Transport, HM Treasury, Network Rail and DfT Operator Limited. Recommendations must be backed by comparisons with UK rail schemes, other UK infrastructure and projects in other major economies.

The exercise follows a difficult period for HS2. In June 2025 the government said phase one could cost about £37bn more than planned if nothing changed, and that around £2bn had been wasted on cancelled phase two works. A review by James Stewart found a lack of ministerial oversight and weak cost control at HS2 Ltd, and the new review is told to build on that work.

The emphasis on specification is the most telling part of the brief. In railway projects, line speed and capacity targets drive almost everything downstream, from curve radii and structures to the number of signals, block sections and power supply points. A requirement fixed early, before designs are mature, can lock in costs that are hard to remove later. The terms of reference name no project, however, so it is not yet clear whether HS2, Northern Powerhouse Rail or smaller enhancement schemes will serve as case studies.

Several points remain open. The document gives no start date, so the six-month clock has no fixed end. It does not say who will receive the final report or whether it will be published. Our coverage of Canada's Alto high-speed rail costs shows how other countries are grappling with the same question.

Sources: Department for Transport, rail infrastructure costs review: terms of reference (28 October 2026, updated 2 November 2026); Department for Transport, HS2 reset plan (18 June 2025).

Photo: the Colne Valley Viaduct under construction for HS2 across a lake at Harefield, April 2024 — 42 Walkers, Wikimedia Commons, CC BY 4.0.

Article written with the help of artificial intelligence from the sources cited, reviewed by the TrainsNews editorial team before publication.