Frontier Airlines has responded to rival carrier Southwest’s baggage policy change with a deal to attract more travelers.

Southwest had a long-standing rule allowing passengers two free checked bags. But the carrier shocked travelers with its recent announcement that the policy will be terminated starting May 28. Southwest will also start charging passengers to pick their seats in another abrupt U-turn from a signature rule that separated the airline from competitors.

The changes have caught the attention of not only travelers but of rival carriers. In a departure from its own rule forcing passengers to pay for luggage, Frontier has offered a special discount code for free checked bags for a limited time. The airline is also offering a free bundle that includes seat assignment and carry-on, both of which normally come with an up-charge.

“We’ve always had heart,” Frontier Airlines CEO Barry Biffle said in a pointed statement. “Some airlines are walking away from what travelers love, but we’re running towards it. Think of this as the ultimate ‘divorce your old airline’ deal. If travelers show us the love, we’ll make these perks permanent.”

Southwest responded with a statement of its own, bashing Frontier’s use of a discount code. “You don’t need a promo code to avoid change fees, cancellation fees, view in-flight entertainment or bring along two carry-on items on Southwest,” Southwest said in a statement.

“We look forward to serving the new Customers attracted to fare above all else, as well as rewarding our most-loyal Customers in our unmatched network connecting more than 850 nonstop city pairs at 117 airports across the United States and 10 international countries.”

Still, the change has sparked backlash from long-time Southwest customers who have vowed to find another airline.

“You were my preferred airline. There is officially ZERO reason to fly with you. Your fares were expensive, but I got free bags, and I could pick a good seat free. It’s no longer worth it to fly with you. Terrible move, Southwest,” one customer wrote on X.

“Welp, after nearly 25 years @SouthwestAir will no longer be my preferred airline. The many things that put them above others are all being axed. Way to alienate your base,” another shared on X.

“My family has always been a SWA family. Taking away the 2 free bags, the open seating, and free changes and cancellations for flights in addition to no longer having competitive prices takes away why loyal customers like us always fly with you. These are bad moves,” someone else wrote on X.

“I have only ever flown @SouthwestAir for the last 10-12 years because of the 2 free bags. Changing this I think is going to be the worst business decision y’all have ever made. This is what puts you above other airlines. Searching for a new favorite airline,” another angry traveler wrote.

Southwest responded, saying simply: “We know the policy updates are a big change for our Customers—we hear you and understand you’re disappointed.”