Spirit Airlines was once a potent force in the U.S. aviation industry. Its demise will reveal how strong that influence had been in recent years when air travel had already begun moving away from the low-fare model that Spirit pioneered.

The airline’s shutdown on Saturday after years of financial troubles resulted in the loss of 17,000 part-time and full-time jobs, and disrupted the plans of tens of thousands of travelers. But aviation experts say it is not entirely clear whether Spirit’s absence will have a significant, long-term impact on the industry, travelers or the U.S. economy.

Airlines will probably have an easier time raising fares and many will absorb Spirit’s gates, check-in counters and other assets at airports in the New York area, Las Vegas, Ft. Lauderdale and elsewhere. But the effect may not be huge, aviation experts said, because Spirit had shrunk a lot recently and was in its second bankruptcy in two years.

“By the time the plug was pulled, Spirit was no longer a major player,” said Michael Boyd, an aviation consultant with the Boyd Group International. “Half the fleet was parked and sold off.”

In May 2024, the airline operated 3.4 percent of all domestic flights, according to Cirium, an aviation data firm. It filed for bankruptcy later that year and again in 2025. Before it shut down, Spirit’s schedule for May would have amounted to just 1.1 percent of domestic flights.

The airline’s diminished business was a major reason many analysts and economists were befuddled by the Trump administration’s efforts to save Spirit, which ultimately went nowhere because the government and the airline’s creditors could not reach a deal.

Most airlines are temporarily offering discounted fares to Spirit’s customers. But many experts believe the company’s absence will result in somewhat higher fares over time, though how much prices will rise is hard to predict.

Spirit’s presence at an airport helped keep fares down, a phenomenon that was studied by economists and earned the name the “Spirit effect.” Even in its reduced state, the company played an important role in forcing other airlines to keep fares low, some experts said.

“It’s at the low-fare end of the spectrum where the market price is established,” said Robert Mann, an aviation industry consultant and a former airline executive. “And it’ll make it easier for everyone else to raise prices at that level.”

But some aviation experts said the consequence may be overstated. Other airlines have spare seats and can absorb many of the customers Spirit catered to. And many people who flew on Spirit tended to travel only when they found very low fares, so they may simply choose not to fly as often now.

Fares would most likely have risen with or without Spirit, some analysts said. Airlines started raising prices in March to make up for the higher fuel costs caused by the Iran war and many have warned further increases are coming.

“It is the industry that is the big winner as unprofitable domestic capacity is further reduced,” William Swelbar, an aviation consultant and economist, wrote in an email. “Fares have to increase or we will lose more airlines to bankruptcy/consolidation.”

Spirit’s slow decline in recent years had broadly helped other airlines, most notably larger carriers like American Airlines, Delta Air Lines, Southwest Airlines and United Airlines. The cities where Spirit flew most included Atlanta, Los Angeles, Detroit, Dallas, Houston, Newark and Miami.Those urban areas are home to important airports for those large airlines.

Those carriers had already found an effective way to compete against Spirit: “basic economy fares.” In the 2010s, American, Delta and United introduced these fares, which were cheaper than standard economy tickets but did not include things like the ability to pick a seat or bring multiple bags on the plane. In recent years, use of these fares has grown a lot, reducing demand for tickets from low-fare carriers like Spirit.

Some smaller airlines also stand to gain by Spirit’s absence, notably JetBlue Airways. JetBlue had already been expanding at Spirit’s home base, Fort Lauderdale-Hollywood International Airport, just north of Miami.

JetBlue said last month that it had added nonstop flights to 21 cities from Fort Lauderdale over the past year, which it views as its third big hub airport after Kennedy International in New York and Boston Logan International. On Saturday, after Spirit shut down, JetBlue said it would add flights from Ft. Lauderdale to 11 more destinations.

“It is full steam ahead in Fort Lauderdale,” Joanna Geraghty, JetBlue’s chief executive, said on a call with investors and analysts last month.

Spirit’s collapse may have a disproportionate effect on some smaller, regional airports. For example, it was the only airline flying to Arnold Palmer Regional Airport in Latrobe, Pa., which is a little more than an hour’s drive from Pittsburgh International Airport.

Spirit also accounted for nearly all flights to Atlantic City International Airport in New Jersey. But other growing budget carriers, such as Allegiant Air and Breeze Airways, which both recently started flying to Atlantic City, may well replace some of the flights smaller airports lost with Spirit’s shutdown.

Frontier Airlines, perhaps Spirit’s biggest competitor in the low-fare segment of the industry, stands to benefit, too. But it is facing many of the same challenges as Spirit did.

“The data suggests that Frontier will win because of its route overlap with Spirit,” Mr. Swelbar said. “But that overlap is also filled with basic economy seats.”

Spirit may help other airlines in another way. Its demise has suddenly made thousands of experienced airline workers available, including more than 2,000 pilots and hundreds of mechanics. United Airlines this weekend began an effort to recruit Spirit employees, saying it would pay special attention to their applications. Demand for pilots, mechanics and other professionals has been high for years.

But Spirit’s assets — planes, airport gates and other real estate, including at LaGuardia Airport in New York — won’t become available immediately. Many of those assets were used as collateral for Spirit’s loans, meaning they will be distributed through bankruptcy court proceedings, which could take some time.

“It’s not going to happen by Monday,” Mr. Mann said, “or next month, or probably for several months.”