In spite of the fact that Southwest Airlines is now one of the largest airlines in the country, it still has a reputation among some consumers of being a plucky upstart that always offers cheaper fares than its old-school competitors, especially for business travelers. But a new study claims that Southwest passengers’ savings often depends on whether or not they check their bags.

Researchers at Topaz International recently published a summary of their study [PDF] comparing Southwests’ airfares to those of eight competitors — American Airlines, Alaska Airlines, JetBlue, Delta, Frontier, Spirit, United, US Airways — to see if consumers’ perception meets reality.

Comparing 100 markets — and only comparing identical routes (i.e., non-stop vs. non-stop, same airports, etc.) — Topaz found that 60% of the time, consumers could find a cheaper base airfare on other airlines. Southwest was still the least expensive on 35% of the routes surveyed, which on its own is nothing to frown at.

But when you add in the price for checking one bag — which is included in the base fare of Southwest flights — the tables turn, with Southwest suddenly becoming the least expensive option in 60% of cases.

And when you add a second checked bag to your total, Southwest becomes the cheapest option 88% of the time.

So what many perceive to be a business travelers’ airline may actually more price-friendly to vacation travelers with multiple checked bags.

This is something to keep in mind, especially since Southwest airfares are not to be found on booking sites like Expedia, Orbitz, Priceline, Travelocity.

[via WSJ.com]

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