Cheapest one-way flights from Ontario to San Francisco in April from $26

Best time to book flights for Ontario (ONT) to San Francisco (SFO) flights at AirHint

AirHint found the following cheapest one-way flights from Ontario (ONT) to San Francisco (SFO) in April 2025 (see full year).

One-Way flights

10 Apr Frontier Airlines direct
17 Apr Frontier Airlines direct
24 Apr Frontier Airlines direct
26 Apr Frontier Airlines direct
18 Apr United direct
22 Apr United direct
19 Apr United direct
29 Apr United direct
25 Apr Frontier Airlines direct
23 Apr United direct

Also check the deals for return flights from Ontario to San Francisco in April.

Skyscanner

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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