Upvote:1
If you're travelling in a group, the cheapest way could be renting a car in Edmonton and returning it in Jasper.
Note that the one-way renting prices of Edmonton<->Jasper are much cheaper than Calgary<->Banff.
Upvote:4
Via Rail has service from Edmonton to Jasper every Sunday, Tuesday and Friday, and return service every Monday, Wednesday and Saturday. The lowest fare I could find was $182.70 return. Probably not what you want.
Greyhound Canada has daily service (though it leaves Edmonton at 12:30 am!) and I was quoted a price of $72.70 return for a 14-day advance purchase on their web site. This is the best option I could find, though with that departure time you should probably plan to spend a few hours sightseeing in Edmonton.
Edmonton also has the "747" bus which runs between the airport and Century Park Station; this costs $5. You'll then need to take the 501 train ($3.20) to Bay Enterprise Square Station to get to Greyhound, which is a few blocks away from that station. The Via Rail train station is not very easily accessible via public transit, but it can be done with a bit of walking.
I wasn't able to find any other options cheaper than Greyhound, though there is always hitchhiking.
Upvote:4
At $80 from the airport directly to Jasper vs $40+ from city center you value your time at nearly nothing. You will waste considerable time traveling to downtown, and then waiting until midnight for the bus. All for about $30.
Or you can land at the airport, get on a highway bus and be in Jasper in about 5 hours.