AirHint found the following cheapest return flights from San Diego (SAN) to San Juan (SJU) in May 2026 (see full year).

Return flights

06 May - 13 May	Frontier Airlines
07 May - 11 May	Frontier Airlines
11 May - 14 May	Frontier Airlines
23 May - 30 May	United
01 May - 04 May	Southwest Airlines
22 May - 31 May	United
21 May - 25 May	Southwest Airlines

Also check the deals for one-way flights from San Diego to San Juan in May.

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 San Diego to San Juan in May from 227€

Return flights