<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by pgary:
Southwest: It usually has the cheapest flights, especially if you can plan ahead.</font>
Southwest being the cheapest is a common misconception. Right now, PVD-SLC is pricing at $198 + tax on Southwest. It's also $198 on UA, AA, NW, CO, US, and DL. Since the fares are identical, I'll take the assigned seats and Elite-qualifying miles on a major. On BOS-SLC, AA is offering $236 + tax. Southwest does not offer BOS service.
Southwest may have a reputation for lower fares, but often the majors are also competitive with their fares.
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Other airlines: They are usually more expensive. However, those same 8 round trips a year between the two locations you mention will get you about 33600 miles.</font>
If all are flown on discount tickets on the same major airline, you will hit first level elite status at 25,000 miles flown (50,000 on DL), which gives you further benefits and mileage accrual. CO and NW offer free upgrades to Elites and a 50% mileage bonus.