英國巴士是怎樣付款的？

可以買車票, 或用 Oyster Card (倫敦的八達通)
如果用 Oyster Card, 就是上車後付款 (同香港一樣)
如果買車票,就是在巴士站用自動售票機買票

2008-09-07 13:44:48 補充：
p.s. I refer to London bus here
For other cities, you probably need to buy ticket from driver