Cheap buses are welcome – but Glasgow cannot afford to rob the railway to pay for them

Anyone who has paid a full adult bus fare from Paisley, Motherwell or Kilmarnock into Glasgow will understand why the £2 cap has been popular. For many families it has turned a daily squeeze into something manageable. That is a good thing, and it should not be lost in the argument that is now beginning.

But the evidence ScotRail's managing director gave to MSPs this week deserves to be taken seriously. In the north of Scotland, where the cap was piloted, the operator lost an estimated £750,000 in a year – about 12% of revenue there. Scale that up to Strathclyde, Joanne Maguire told the Transport Committee, and the hit could be as much as £20 million.

Two public services competing for the same passengers

There is something odd about a policy in which one publicly funded transport service undercuts another. ScotRail is owned by the Scottish Government. Every passenger tempted off a train and onto a capped bus is, in effect, money moved from one public pocket to another – with the rail operator left to explain the gap.

Ms Maguire was careful to say it is "very early days" and that ScotRail has not yet seen a significant impact. That is fair. But she also confirmed there have been no discussions with ministers about extra funding to cover any losses. That should worry anyone who relies on trains to get to work.

The risk of cuts by the back door

The danger, as Liberal Democrat MSP David Green warned, is that a hole in ScotRail's budget eventually shows up as fewer services, shorter trains or cancelled improvements. Rail and bus are not perfect substitutes. A train from Glasgow Central to Ayr or from Queen Street to Edinburgh does a job no bus can match for speed, and a weaker railway would be a poor trade for cheaper short bus hops.

Integrated, not competing

The answer is not to scrap the cap. It is to plan transport as a single network. That means fares that make sense across bus and rail, smart ticketing that lets people switch between them easily, and a funding settlement that recognises the knock-on effects of one policy on the other.

Transport Scotland says it expects "travel patterns to evolve" and is monitoring the impact. Monitoring is the minimum. With the Scottish Budget due next month, ministers should set out now how they will protect rail services if the losses Ms Maguire described begin to materialise.

Cheap buses and a reliable railway should not be an either/or for Glasgow. It is up to the Government to make sure they are not.