Off-peak
What it really means
A cheaper ticket you can only use outside the busiest times, usually after the morning rush (about 9:30am) and not during the evening rush on some routes. Always check the exact times for your route.
Context, tips & common mistakes
Off-peak tickets are cheaper because they ban you from the busiest trains — and the catch is that 'peak' has no single national definition: the restricted times vary by operator and route, with morning peak typically until mid-morning and, into and out of big cities, an evening peak as well. The ticket or booking page states the exact restriction; the journey planner only shows valid trains once you select the ticket type.
Boarding a peak train with an off-peak ticket is not a rounding error — it means paying the difference at best, a penalty fare at worst. Two safe habits: check the first valid train after morning peak on your specific route (a famous cliff-edge where the fare drops sharply), and remember weekends and bank holidays are generally off-peak all day. Super off-peak tickets tighten the windows further in exchange for the lowest walk-up price.