The Regulations setting minimum service levels (MSLs) during rail strikes are now in effect. This Insight explains why and how these Regulations are being made and how they will operate.

Where do the minimum service levels come from?

The Conservative manifesto for the December 2019 general election pledged to introduce legislation to “require that a minimum service operates during transport strikes.”

The Strikes (Minimum Service Levels) Act 2023, which received Royal Assent on 20 July 2023, allows employers to issue ‘work notices’ needed to meet MSLs, which unions and workers would have to comply with or face losing protections against being sued or dismissed.

The Act allows the Secretary of State to make regulations setting out the MSLs required in six specified sectors during strikes. One of these sectors is “transport services”.

Following consultation, the Government response set out plans to regulate around three specified types of passenger rail services and a MSL of 40% of timetabled services.

Who do these restrictions on strikes affect?

Nothing in the Regulations or in the 2023 Act requires any operating companies to operate the specified MSLs. Rather they give operating companies and other employers a power to issue work notices to staff to meet the specified MSLs, if they so wish.

Employers affected by these restrictions

Work notices can be issued by:

  • train operating companies (TOCs), which run passenger rail services (except for open access and international operators)
  • railway infrastructure managers, which are responsible for rail infrastructure, such as tracks and overhead lines
  • light rail operators, which run tram or metro services.

The Regulations cover TOCs and railway infrastructure managers regardless of what part of government their contract is with (including devolved administrations and local government). Note that the Regulations do not apply to Northern Ireland Railways.

Light rail services are defined in Section 2(1) (a) – (k) of the Regulations, and include London Underground, Docklands Light Railway, Glasgow Subway and Tyne and Wear Metro, in addition to light rail systems such as Manchester Metrolink and Sheffield Supertram.

Employees affected by these restrictions

For train operation services and light rail services, the main roles likely to be in scope are drivers and guards (where applicable), as well as other services which enable train services to run (such as support staff). Rolling stock maintenance is excluded, though the Regulations specifically include staff who undertake “the refuelling of any locomotive or other rolling stock”.

For rail infrastructure services, the Regulations cover staff required for the day-to-day operation of the railway (including signallers, level crossing operators, staff involved in the operation of communication equipment or power supply, and so on). They also cover reactive maintenance staff to deal with any infrastructure issues that arise.

How are minimum service levels defined?

Minimum service levels for ‘train operation services’ and ‘light rail services’

For ‘train operation services’ and ‘light rail services’ minimum service levels are defined as “the equivalent of 40% of the timetabled services”. Timetabled services for train operators are set out in the National Rail Timetable for the relevant day.

For comparison, in the 12 months between 1 October 2022 and 30 September 2023 there were 26 strike days, and the Office of Rail and Road estimated an average of 36% of timetabled services operated on the strike days. (This varied between 13% and 62% of services operating on each strike day, depending on which union(s) were on strike.) Some TOCs may run significantly more (or less) than the average, depending on, for example, whether staff who normally perform other roles can cover for striking staff.

The Regulations do not specify how services should be divided throughout the day. For example, an operator could choose to mainly provide services in the peak period, or to spread service throughout the day.

Services must be on routes normally operated by that train operator, but can be re-timed and/or have different stopping patterns.

Light rail services are similarly based on the published timetable for that network.

Minimum service levels for ‘infrastructure services’

For ‘infrastructure services’, the Schedule to the Regulations identifies priority routes, where the infrastructure must be available between 6am and 10pm. These are shown in the map below.

They also include any part of the network within 5 miles of the priority network that is used for storing trains or is connected to a freight terminal, to allow trains to enter service and freight services to be provided.

A map of indicative reail routes identified by the Department of Transport. These are primarily the UK main lines plus some commuter routes around the larger cities.

Priority routes make up about 40% of the national rail network. These primarily comprise main lines in Great Britain and commuter routes around larger cities, including London, Glasgow, Liverpool and Birmingham. They also include some branch lines, such as the Island Line and Derwent Valley Line, but don’t include any routes in Wales (other than Cardiff to the Severn Tunnel), Cornwall or Scotland north of the central belt.

If infrastructure services and train operation services were both on strike at the same time, then some operators may have limited options to provide 40% of their timetable service if infrastructure is only available on these priority routes. This would particularly affect the Wales and Borders franchise.

How and when does this take effect?

The Strikes (Minimum Service Levels: Passenger Railway Services) Regulations 2023 were signed into law on 7 December 2023 following approval by both Houses and came into force a day later on 8 December 2023.

The Regulations can apply to any strikes from the day after they came into force, even if the strike ballot had already taken place before the Regulations were made.

The Regulations were laid before Parliament on 7 November 2023, alongside two other sets of MSLs Regulations in border security and ambulance services.  The passenger rail regulations were approved by a Commons vote on 28 November and a Lords vote on 6 December.

Alongside these regulations, a Code of Practice on reasonable steps to be taken by a trade union (minimum service levels) has been approved by Parliament and entered into effect on 8 December 2023. This was required before any minimum service regulations could take effect.

Further reading

Commons Library, Strikes (Minimum Service Levels) Bill 2022-23

About the authors: Patrick Brione is the employment law and policy specialist, and Mike Benson is a transport researcher in the House of Commons Library. The maps were produced by Carl Baker, a statistics researcher in the House of Commons Library.

Image by William © –

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