Deal found on September 27, 2026
St. Louis to San Juan
$231$39642% off
Round trip
St. Louis to San Juan usually costs around $409 round trip, and Frontier has it down to $231 right now, 43% off. Puerto Rico requires no passport for US travelers and is a great year round Caribbean pick, especially as it cools off back home this fall.
Travel dates
Dates in December
e.g. Dec 7 – Dec 16 · 9 nights
Date options
3 at this price
Lowest we've seen
$171
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