Ben Mutzabaugh

USA TODAY

The number of U.S. airlines flying to Cuba keeps thinning out.

Spirit Airlines has become the latest to throw in the towel on regular passenger service to country. It's now the third U.S. carrier to do so after similar announcements earlier this year from Frontier and Silver Airways.

Spirit’s Havana-Fort Lauderdale flights will end May 31, according to the South Florida Sun-Sentinel.

Other airlines, including American and JetBlue, also have reduced capacity to Cuba, though they have not dropped any routes there.

Spirit’s decision to exit Cuba comes only about eight months after regular passenger flights resumed for the first time in nearly 50 years.

When Cuba opened up to U.S. airlines last year, routes and capacity to the island were capped and carriers had to apply for the rights to serve the Cuba’s international airports. Nearly all of the big U.S. airlines rushed in with requests to fly to the island – especially on routes to Havana.

Against that enthusiasm, however, some industry executives openly wondered whether demand would live up to the hype.

Despite the loss of Spirit's service, South Florida travelers will continue to have numerous options for non-stop flights to Havana. American and Delta each fly to Havana from Miami while JetBlue and Southwest fly there from Fort Lauderdale.

USA TODAY: First U.S. commercial flight in 5 decades lands in Cuba (story continues below)

Without regular airline service to the island in five decades, there was little data available to carriers in trying to assess potential demand for flights to new destinations. And unlike other foreign markets, Cuba remains a unique and highly regulated place for U.S. airlines to do business.

As for Spirit, it had been flying two daily round-trip flights to Havana from Fort Lauderdale, its biggest base. Those flights began just this past December.

“We really wanted [Fort Lauderdale-to-Havana] to work, especially being South Florida’s hometown airline... and the ultra-low cost leader to the Caribbean, but the costs of serving Havana continue to outweigh the demand for service,” Spirit CEO Bob Fornaro says in a statement to the Sun-Sentinel. “Due to overcapacity and the additional costs associated with flying to Cuba, we don’t find it sustainable to continue this service while maintaining our commitment to pass along ultra-low fares to our customers.”

Both Frontier and Silver also cited overcapacity in their decisions to exit the market.

TWITTER: You can follow Today in the Sky editor Ben Mutzabaugh at twitter.com/TodayInTheSky

TODAY IN THE SKY: Booking a flight to Cuba? Here's what to expect now (September 2016)

IN PICTURES: U.S. airlines now flying to Havana for first time in five decades