It’s been a horrible year for plane maker Boeing. But Boeing’s troubles are quickly becoming troubles for its major customers, which in the United States include United Airlines and Southwest Airlines. Because Boeing is now facing increased scrutiny by regulators, production of its planes has slowed, which means deliveries to airlines have slowed as well.

This is especially bad for Southwest, which only flies the beleaguered Boeing 737 series. The airline reported its first-quarter 2024 financial results today, and with the report, the company said it expects capacity to increase 4% in 2024, compared to a previous estimate of 6%.

As Bloomberg reports, this lower estimated growth comes at a time when the skies are set to be busier than ever this summer and follows Boeing again reducing the number of aircraft it will deliver to Southwest.

But for Southwest passengers who are used to flying to several airports, things are going to get even worse. That’s because Southwest has announced it will cease flying to four airports—three in America and one in one of Mexico’s most popular tourist destinations that Americans love flying to.

These are the airports Southwest will cease flying to as of August 4, 2024:

• George Bush International Airport (IAH) in Houston, Texas
• Bellingham International Airport (BLI) in Bellingham, Washington
• Syracuse Hancock International Airport (SYR) in Syracuse, New York
• Cozumel International Airport (CZM) in Cozumel, Mexico

If you regularly fly Southwest to any of the above airports, it’s a good idea to start planning arrangements on alternative airlines after the beginning of August. 

But the Southwest airport shakeup doesn’t end there. The airline also says it will “significantly restructure” other markets it flies to. This will include reducing capacity at two of America’s busiest airports: O’Hare International Airport (ORD) in Chicago and Hartsfield-Jackson International (ATL) in Atlanta.

Of course, while Southwest will stop flying to four of the airports it currently serves, the airline will continue to fly as normal to the majority of airports it counts as destinations. As of the time of this writing, Southwest says it serves 121 destinations across the United States and 10 other countries. 

Shares of Southwest Airlines stock were down almost 8% on Thursday in premarket trading.