United trolls Southwest's boarding process in unusual ad campaign

United Airlines wants to help you avoid Southwest Airlines' dreaded "C" boarding group.

Yes, you read that correctly.

The Chicago-based carrier is launching an unusual ad campaign Thursday, offering up courtesy reminders to Southwest passengers to remember to check in 24 hours before their flights in order to snatch a more desirable boarding group.

Travelers can go to NotGroupC.com and get a call from United in time for the check-in window.

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"Hello, United Airlines here, reminding you to check in for your Southwest flight, so you don't end up in boarding group C," the call says, a recording of which was provided to TPG ahead of the campaign's launch. "For your next flight, think about giving United a fly — we let you choose your seat in advance."

Southwest is unique among U.S. carriers in that it does not assign seats.

Instead, it assigns boarding numbers in three separate groups: A, B and C, based on the order in which passengers check in. Travelers then line up in the gate area according to their boarding group and number.

More: Everything you need to know about the best seats on Southwest Airlines

There are some ways to avoid the dreaded C group, such as having Southwest status or purchasing a Business Select fare or EarlyBird check-in.

However, United would like to add its new, tongue-in-cheek reminder service — what it calls a "Courte-C call" — to that toolbox.

“We’re sounding a lighthearted alarm to remind travelers who may not choose United that there’s an easier way to travel,” Maggie Schmerin, United's managing director of advertising and social media, said in a statement.

“Ideally, next time these travelers are flying, they don’t need a 24-hour notice to check in because they’ve chosen to fly with United, where customers can select their seat in advance and therefore avoid the consequences of ending up in the competition’s Boarding Group C.”

The new digital campaign is going live in three key markets where United competes aggressively against Southwest. Travelers based in Houston, Denver and Chicago will see the ads on their computer screens and smartphones.

Across Houston's two airports, United had a 56% domestic market share in July, which is the most recent government traffic data available, while Southwest had a 26% domestic market share. United only operates at George Bush Intercontinental Airport (IAH), while Southwest is primarily at Willam P. Hobby Airport (HOU), with some flights at IAH.

At Denver International Airport (DEN), United had a 46% domestic market share, while Southwest had a 29% domestic market share in July.

Across the two airports in Chicago, United had a 36% domestic market share, while Southwest had a 27% market share. United only operates at O'Hare International Airport (ORD), while Southwest counts Midway International Airport (MDW) as one of its busiest bases but still offers a number of flights from ORD.

In recent years it's been unusual — but not unheard of — for airlines to attack one another by name in advertising. In 2021, United launched another campaign in Denver going after Southwest. One ad read, "United: Nonstop to Hawaii's beaches. Southwest: Some stops to Hawaii's beaches."

More: What is United Airlines' elite status worth in 2022?

For all of United's ribbing of Southwest and its boarding process, selecting seats on United is not always free, especially if a traveler purchases a basic economy fare or lacks Premier status.

Travelers who purchase basic economy — United's cheapest fares — are able to purchase a seat assignment. If they don't, they'll be automatically assigned a seat, which can include less desirable middle seats — the same types of seats that Group C passengers often have to choose from.

United also designates many of its more desirable seats to be "preferred seats." These seats are often window and aisle seats and tend to be closer to the front of the cabin. While these are free for Premier members to select, if you lack United status, you'll shell out some money for them — even if you didn't purchase basic economy.

However, even if United isn't the most perfect airline to go after Southwest's boarding process, it's hard to deny that this unusual, direct campaign is quite entertaining.