Fares shown are modelled estimates, not live quotes.
Other budgets from San Francisco:
Lowest Route Estimates from San Francisco Under $400
Sorted by modelled price estimate, not live fare data.
How to Find Flights Under $400 from San Francisco
Book 6–10 weeks in advance
This is typically the sweet spot for international fares from San Francisco. Too early and airline seats aren't discounted yet; too late and inventory is tight. The $400 threshold is easiest to hit in shoulder season.
Fly mid-week
Compare Tuesday and Wednesday departures from San Francisco with weekend dates before booking.
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Frequently Asked Questions
Are there really international flights from San Francisco under $400?
22 routes from San Francisco have modelled round-trip estimates at or below $400. These are based on route distance and region, not live or historical fares.
When is the best time to find flights from San Francisco under $400?
Shoulder seasons (April–May, September–October) can offer lower prices. Compare mid-week departures and nearby dates before booking.
What is the cheapest destination from San Francisco?
Based on modelled estimates, Los Cabos is one of the lowest estimated routes from San Francisco at around $105 round trip. This is not a live fare.
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