The company, Travelocity.com, is said to have violated the 45-year-old U.S. ban on commercial dealings with the Communist island nation more than 1,500 times between January 1998 and April 2004.
According to the Treasury complaint, the company "provided travel-related services in which Cuba or Cuban nationals had an interest by arranging air travel and hotel reservations to, from, with or within Cuba without an OFAC (Office of Foreign Assets Control) license."
There is no comprehensive ban on travel by U.S. citizens to Cuba. Special tours are permitted for academic, religious, journalistic and humanitarian purposes, but their organizers must obtain the required permits from U.S. authorities.
A Travelocity spokesman said the violations had been unintentional, resulting from technical faults in the company's booking system that have since been corrected.
"In no way did the company intend to allow bookings for trips to Cuba, and the company has fully cooperated with OFAC and implemented corrective measures," Joel Frey said in an e-mail statement.