Labour’s current one-at-a-time approach builds off of the work of its predecessors in government. Several operators – including LNER, Northern and Southeastern – were brought into public ownership by the Conservatives from 2018 onwards.

In those cases, nationalisation was taken as an emergency measure rather than a deliberate policy – in response to financial difficulties, in the case of LNER, or because of dismal performance, in the case of Northern.

Additionally, ScotRail and Transport for Wales were brought into public ownership by their respective devolved governments, and their train operations are not expected to be merged into Great British Railways.

Labour’s strategy for the remaining operators is driven by legal reality – which experts say could be helpful given how fragmented rail in Great Britain has become.

“You can’t do it in one go,” said Marcus Mayers, the managing director of the Rail and Station Innovation Company. “If you try to merge 22 companies in one go – you don’t have the ability to build the system, to join it together that quickly.

“So you build an operation which is capable of ingesting organisations, and is capable of ingesting organisations at the rate of one every three months. That makes sense.”

Will nationalisation improve the railways?

The prime minister, Keir Starmer, has previously said his government would not be nationalising rail out of ideology but because of what it could deliver for passengers.

“We’ve tried privatisation for two or three decades and it’s a complete mess,” the Labour leader said in April 2024. “Everybody who travels on the trains has been affected by the cancellations and delay.”

Privatisation was undertaken by the Conservatives in the 1990s, after decades of falling ridership under the nationalised British Rail.

From 1948 onwards the annual number of journeys on Britain’s rail network fell consistently, from a peak of more than 1 billion a year in 1950 to a low of 0.6 billion in 1982.

After privatisation, rail journeys recovered significantly, reaching a new peak of 1.7 billion by 2017.

“Privatisation sparked a railway renaissance,” said Patrick McLoughlin, the transport secretary under David Cameron, in a speech in 2013.

However, the impact on other aspects of train travel has been more mixed.

One of the original selling points of privatisation was that competition for franchises would bring better value for the taxpayer.

While the industry remained subsidised overall, some major commuter franchises went on to pay a return.

Yet in the past few years, after huge falls in passenger numbers during the coronavirus pandemic, the amount the government pays to operators in public subsidy has ballooned to record levels.

“The government is still forking out £12bn on operational subsidy, plus HS2 is another £7bn, plus extracurricular investment projects on the existing railways,” Glaister said.

“That’s a very great deal of money in the context of the public expenditure crisis.”

Costs have risen for passengers, too. Rail fares have become less affordable since privatisation, rising faster than average earnings in the same period.

Today it costs about £8.90 to take a 50km (31-mile) journey by rail, based on how much revenue rail operators collect for each kilometre travelled on their network.

When adjusting for inflation, that same journey would have cost £7.54 in 1994.

The rising cost of rail comes amid widespread dissatisfaction with the reliability of Great Britain’s trains.

Last year was the worst year for cancellations nationally since 2015, according to statistics produced by the Office of Rail and Road.

Labour has pledged to improve reliability and affordability with nationalisation, banking on a unified Great British Railways to end what critics see as an overly fragmented system.

“It’s possible, because there’s efficiencies of integration of track and train, which might mean that problems get solved more quickly,” Mayers said.

“You may be taking out the commercial imperative to drive reliability, but you’ve also got more collaboration about how to achieve it. So it’s a fine balance, and whether it will work or not is still open for debate.”

Others are sceptical of how much more efficiency can be wrung out of the system.

“Governments frequently say: ‘Oh, we’ll make the railways more efficient, we’ll buy lots of new equipment, we’ll employ less people to do the work,’” Glaister said.

“But the industry has been trying to do that for years and years, and the regulators screw that down to the absolute bottom in their settlements. And I don’t think there’s a lot of, as it were, undiscovered efficiencies to go for.”

A DfT spokesperson said: “Through public ownership and the creation of Great British Railways, the government is fundamentally reforming how our railways are run, putting passengers first.

“Public ownership will deliver a railway that is more accountable, efficient, and reliable – resulting in greater opportunities for communities and significant growth.

“It is not a silver bullet, and issues inherited from private sector ownership will take time to root out, but we expect public sector operators – and Great British Railways once it is established – to focus relentlessly on improving reliability, punctuality and other aspects of the service that matter most to passengers, and we will hold them to account for doing so.”