Why is my Railcard discount less than ⅓ off?

Your Railcard discount is less than ⅓ off because, for some railcards, there’s a minimum fare that applies at certain times of the day. and that might be the reason.

For example, the 16-25 Railcard has a minimum fare of £12.00 on journeys starting between 04.30 and 10.00 on Mondays to Fridays.  This minimum fare does not apply on public holidays, at weekends and during July and August.