You pay your fare when you board the buses. Exact Fare Only applies. The drivers are not allowed to handle cash. You put your fare into the box next to the driver. No change! But let me tell you a secret - you can ask for a 'change voucher'. The driver will give you a receipt which you can take to the main Bus office (on Wood Street close to the Bus Station) and exchange for money.
Cardiff is divided into Fare Zones. If you travel in one fare zone, you pay the least. If you have to cross one or more Fare Zones, you need to pay more for your ticket. Tell the driver where you want to go and s/he will tell you the cost! You can also buy return tickets.
The fares go up regularly. It is currently (Spring 2008) £1 for travel within the centre zone, which includes Cardiff Bay. A return ticket is twice the price of a single. Or there are various Travelcards are also on sale, for different periods and different zones. For £3 you can buy an all-day adult ticket for unlimited travel on that date.


