Southwest Airlines, the largest carrier at BWI Marshall Airport, will start charging many customers for checked bags in late May, marking the end of a longtime perk for the airline’s passengers.

Only certain customers with thousands of frequent flyer miles, and those flying on premium fares, will be able to check two bags for free. Additional “select” members will be able to check one bag, the airline said in a news release.

The airline will also be introducing new “Basic” fares. The changes take effect May 28, the airline said.

The Dallas-based airline, which has its busiest East Coast hub at BWI, has faced pressure from activist investors to return to pre-pandemic levels of profitability. Last year, a boardroom feud between the airline and Elliott Investment Management led to Southwest adding five of the hedge fund’s nominees to its board in November. As part of its restructuring, Southwest announced its first mass layoffs this year.

But the airline risks losing customer loyalty and market share by doing away with popular, decades-long perks that set it apart from even “no frills” rivals, industry experts say. The airline built its brand by embracing a customer-first, welcoming approach to serving passengers.

“The other companies Southwest is starting to look more and more like are not nearly as financially stable or financially profitable as Southwest Airlines,” particularly for decades leading up to the pandemic, said Marbue Brown, a customer experience analyst and consultant. “Every time you have a change like this, it is an invitation to your customers to explore other options,” Brown said.

Sitting at BWI on Tuesday, Paula McVeigh said she might do just that after the fee increase.

A Punta Gorda, Florida, resident, McVeigh says she will be more likely to check into other carriers to look for the most economical flight. She said she had flown the airline for years, often with her dog under her seat.

“We pay for her, and I’ve heard that Southwest is going to start charging for bags, and that makes me so sad,” McVeigh said. “I know everyone else is doing it.”

Kevin Stone, a Timonium resident who has been flying Southwest for about 20 years, now mostly for business, said he doesn’t like the idea of charging for bags.

But “everybody else has been doing it for a long time,” he said. “As long as the prices are still the same, I’m still probably going to fly” Southwest.

Brown argued that “customer obsessed” companies, such as Southwest, Amazon, Zappos shoes and Chick-fil-A, which he analyzed for his book, “Blueprint For Customer Obsession,” are strong financial performers, proving that strategy works.

For Southwest, ending the “two bags fly free” policy is the latest in a series of steps as it aims to boost revenue and adjust to a post-pandemic market.

In July, the airline announced plans to do away with its more than 50-year tradition of open seating, saying it would start assigning seats and selling premium seating, a bid to win more business and corporate travelers. Southwest became the nation’s biggest low-cost carrier because of its open economy seating.

Southwest said at the time it changed course after finding that passenger preferences about seating options have changed and to generate revenue. The airline also redesigned its boarding model and introduced redeye flights, a response, some experts said, to trouble filling low-cost airline seats.

The carrier started its unusual boarding process as a way to save money instead of assigning passenger seats. The airline requires customers to check in 24 hours before departure, or pay extra fee, to guarantee a better place in line.

Other no-frills airlines may charge lower fares, but tend to charge fees elsewhere, Brown said.

By watering down its free-bag policies, Southwest is “doing more and more of what the other companies are doing and becoming a lookalike with other companies,” Brown said. “They’re losing an edge from the customer perspective, but long term it doesn’t bode well financially.”

Officials with Elliott Investment believe otherwise.

The airline’s new direction is expected to “enhance business performance, drive operational execution and evaluate additional changes to create long-term shareholder value,” John Pike, a partner with Elliott had said in announcing board changes in November.

McVeigh says she’s floating an idea for Southwest that calls for compromise: Let the first bag fly for free and charge for the second one.

“At least that would help the customers and give Southwest some money too,” McVeigh said.

Going forward, Brown said, Southwest may rely on its employees, known for creating a lighthearted flight environment, to give it an edge. Competitors, meanwhile, may look to expand routes.

One rival, Spirit Airlines, announced such a move on Monday, launching service to eight new or resuming destinations from BWI starting in May. The new service will expand Spirit’s BWI presence to 21 destinations and 23 peak-day departures.

Spirit’s new, nonstop destinations include Charleston, South Carolina and Milwaukee. Resuming routes include Charlotte, Chicago, Detroit, Raleigh-Durham and San Antonio.

Photojournalist Kim Hairston contributed to this story.

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