I was really bored tonight, so I ended up doing this.....

Okay, here's how it works: I used expedia.com and expedia.ca to compare prices on three different markets for each country. The first was a transcon, the second a midcon, and the third a "shuttle" type market. The multipliers used were (.77 USD to 1 CAD) and (1.30 CAD to 1 USD). All flights depart on 3/26/04 and return on 4/5/04.

Here's what each number below means
1-tax(USD)
2-tax(CAD)
3-total cost of ticket(USD)
4-total cost of ticket(CAD)
5-tax as total % of cost

Here are the results

US Domestic
JFK-LAX $35.30/$45.89/$261/$339.30/13.5%
BOS-ORD $34.21/$44.27/$245/$318.50/14.0%
LGA-DCA $27.28/$35.46/$156/$202.80/17.5%

Canadian Domestic
YUL-YVR $86.89/$112.84/$502.81/$653/17.3%
YYZ-YWG $43.24/$56.15/$251.79/$327/17.1%
YYZ-YUL $47.75/$62.01/$248.71/$323/19.1%

Summary: Canadians pay somewhere in the neighborhood of 1.5-4.0% more for their domestic tickets than Americans do. As the distances get smaller, the divide tends to lessen somewhat. I was actually surprised and thought that Canadians paid about 10% more in taxes than we did.

I also decided while I was at it to compare this to the transborder market.

Transborder
BOS-YVR $71.40/$92.82/$390/$507/18.3%
IAD-YYC $84.89/$110.36/$440/$572.00/19.2%
LGA-YYZ $50.55/$65.72/$233/$302.90/21.7%

Summary: Taxes on transborder tickets are somewhere between 4.2-5.2 percent higher than they are on US tickets and 1-2 percent higher than on Canadian domestic tickets.

Enlightening, flawed, or just boring? Comments appreciated.

GSP flyer