AirHint found the following cheapest return flights from Trenton (TTN) to San Juan (SJU) in January 2026 (see full year).

Return flights

10 Jan - 14 Jan	Frontier Airlines
22 Jan - 26 Jan	Frontier Airlines
24 Jan - 31 Jan	Frontier Airlines
09 Jan - 12 Jan	Frontier Airlines
10 Jan - 18 Jan	Frontier Airlines
09 Jan - 14 Jan	Frontier Airlines
22 Jan - 25 Jan	Frontier Airlines
22 Jan - 27 Jan	Frontier Airlines
08 Jan - 12 Jan	Frontier Airlines
24 Jan - 28 Jan	Frontier Airlines
31 Jan - 05 Feb	Frontier Airlines
25 Jan - 01 Feb	Frontier Airlines
31 Jan - 06 Feb	Frontier Airlines
31 Jan - 07 Feb	Frontier Airlines

Also check the deals for one-way flights from Trenton to San Juan in January.

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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Cheapest return flights from Trenton to San Juan in January from 246€

Return flights