Readers’ forum: Impact of joint railcard on husband’s travel expenses.

I have a client who is self-employed and whose work takes him across the country. He usually travels by train and claims his train fares as an allowable expense under normal principles. On some occasions his wife will join him to keep him company on the train and for an opportunity for her to wander around different cities while her husband is working. 

I have no worries about the purpose of the husband’s journey – that is undoubtedly for work; his wife’s company is entirely incidental to the business journey. 

My question concerns the fact that they have recently acquired a railcard which allows them a 33% discount if they travel together. For example the husband can undertake a journey alone and be charged £100 which would be deductible from his trading profits. However if the two travel together the rail company will charge them £67...