Taking a bus is the cheapest way to travel from London to Cardiff. Buses traveling from London to Cardiff depart from London's Victoria Coach Station and taking at least 3 hours to arrive at Cardiff's Sophia Gardens bus station. Over 30 buses travel from London to Cardiff per day, with the earliest departing London at 6:13 a.m. All buses that travel from London to Cardiff are operated by National Express.

Technically taking a flight is the fastest way to travel from London to Cardiff; however, when travel time to and from London and Cardiff's airports is taken into consideration, taking a train is actually the fastest way to travel. Additionally, there is only 1 direct flight between London and Cardiff per day. Trains traveling from London to Cardiff depart from London's Paddington train station and take 2 hours to arrive at Cardiff's Central train station. All trains traveling from London to Cardiff are operated by First Great Western with 10 trains departing London per day.

Taking the train is the most popular way to travel from London to Cardiff. Taking the train is over an hour faster than traveling from London to Cardiff by bus and 4 hours faster than taking a flight when travel time to and from London and Cardiff's airports is taken into consideration. Trains are also €29 cheaper than flights on average. Buses remain an attractive option for travelers trying to save some money while traveling.