Frontier Airlines will debut service from San Juan's Luis Munoz Marin Airport to Barbados on July 3 and to Trinidad on July 11.
Both flights will operate three times a week to Barbados' Grantley Adams Airport and to Piarco Airport in Trinidad. Barbados flights will take place on Mondays, Wednesdays and Saturdays, Trinidad service on Sundays, Thursdays and Fridays.
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Earlier this month, the airline launched routes from San Juan: three times a week on Sundays, Tuesdays and Thursdays to St. Croix in the U.S. Virgin Islands and twice weekly on Mondays and Fridays to St. Maarten.
All flights operate using Airbus A320s.
"This new crew base underscores just how vital San Juan has become to our operations as we continue to grow our service between Puerto Rico and the U.S. mainland as well as to other islands in the Caribbean," said Barry Biffle, CEO of Frontier Airlines.