Which airline is the cheapest airline?

Depence on where in Canada you want to fly to... Oasis Hong Kong have the cheapest ticket at around HKD4500 include tax, but they only fly to Vancouver...
For Air Canada and Cathay Pacific, both of them fly to Vancouver as well as Toronto, but fare are generally HKD6000 plus exclude tax... But from time to time, promotion can be found at around HKD4000 exclude tax for Cathay Pacific or Air Canada...
If you are hoping for a standard services but not necessaryly direct flight, you can consider and have a check on airlines like China Airlines, Asiana, Korean Airlines, ANA and JAL as all of them will fly via some Northern Asia countries, and their fare would be similar to HKD4000 exclude tax even during peak season...
Since there are very limited direct services between Hong Kong and Canada... But the demand are way too heavy... Therefore, I would suggest you to look early for the tickets... As it could get as expensive as HKD10000 include tax during peak season...

2007-07-18 22:02:45 補充：
s9801023, 你就唔識... 甘泉已經係6月1號開左香港 - 溫哥華航線啦... 要話人就自己CHECK清楚先啦...

Oasis Hong Kong already started their service to Vancouver since June 28. Six flights per week.
For non-stop flights, I would prefer Oasis over Air Canada. I suppose their service and entertainment are much better than Air Canada.

Air Canada is way cheaper than Cathay Pacific.

pachubb, 你識吳識ga, oasis 邊道有機去加拿大呀?