In 2026, if you board a peak-time train with an "Off-Peak" ticket, particularly on the UK National Rail network, you are technically traveling without a valid fare for that specific service. Typically, the ticket inspector will require you to pay the "excess fare," which is the difference between the price of your Off-Peak ticket and the cheapest "Anytime" or "Peak" fare valid for that journey. However, policies have become stricter; on some routes, you may be issued a Penalty Fare, which in 2026 can be as high as £100 plus the price of the full single fare. While some staff may allow you to move to the next valid train at the next station, you are legally liable for the surcharge once the train has departed. It is always advisable to check the "Restriction Code" on your digital ticket before boarding to ensure your departure time falls within the permitted Off-Peak window.