On Friday, Southwest planes started flying into New York's LaGuardia Airport.

Not really.

On February 4, the new ATA/Southwest codeshare truly takes effect. For a slew of routes across the country, you can now use a Southwest ticket to fly on an ATA plane, or vice versa, switching planes in Chicago to the other airline as if they were one. Flying from Albuquerque to Minneapolis? You'll be on Southwest to Chicago, and then on ATA to Minneapolis with one ticket. And you can buy your ticket from either ATA ( or Southwest (

We covered the ATA/Southwest codeshare right before it started, based on comments made by Southwest executives in a conference call. But we were wrong about a whole bunch of things. For instance, no, routes to and from Chicago aren't covered -- only certain routes with connections through Chicago. That's a huge disappointment, as the New York-Chicago route is aching for more competition.

We also assumed that Southwest would be the fare leader on the codeshared routes; on their conference call, they assured us that the codeshare cities would be treated like other Southwest cities during Southwest's perpetual sales. Wrong again.

Southwest has been pricing the codeshare cities higher than most Southwest cities; typically, you'll have to pay at least $99 on a weekday and $132-$149 on a weekend, plus tax, each way to fly to or from a codeshare city. And that's with a 21-day advance purchase, on a tiny number of available seats. More potent sales, like Southwest's "Featured Destination" sales, don't seem to include the codeshares at all.

We checked ATA and Southwest's fares against other airlines on 10 routes for March dates, and we were disappointed. Many of Southwest's lowest fares weren't available, and even when they were, sometimes other airlines had lower fares. Looking strictly at available fares, Southwest charged the least on two of our routes. ATA had the lowest fare on one route, beating Southwest by $6 on the Little Rock-New York route we checked. On seven other routes, other airlines had the lowest fares. On one route (Newark to Sacramento), Southwest charged $180 more than American Airlines.

This all emphasizes that once again, and as usual, you must shop around. At the very least, if you're in or are going to one of the cities newly served by the codeshare (Boston, Denver, Honolulu, Minneapolis, New York, San Francisco, Sarasota or St. Petersburg), check fares on, and on an aggregator site like

For low Southwest-style fares, we were willing to overlook our nerves about merging Southwest's ultra-efficient, no-reserved seating system with ATA's more laid-back style. Now we're more edgy. We'd love to hear if travelers are having any trouble making the transfers.

Have you flown on an ATA/Southwest codeshare? Tell us in our Air Travel Message Boards.